Mack Vmac Ii V mac 2 Service Manual – PDF DOWNLOAD

®

V-MAC II SERVICE MANUAL

JULY 1998 (REVISED)

8-206

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PLEASE LET US KNOW! Your comments and suggestions will help us improve this manual!

Please complete and mail this form or FAX your comments to: (610) 709-3800.

Manual: _______________________________ Publication Number: _______ Vehicle Model: _________________________ Model Year: ______________ Do you find procedures properly organized and easy to follow? m Yes

m No

If not, please explain: ______________________________________________ _______________________________________________________________ _______________________________________________________________ Manual page numbers: _____________________________________________ Are there any important procedures or other information presently not in this manual that you would like to see included? m Yes m No If yes, please describe: _____________________________________________ _______________________________________________________________ _______________________________________________________________ Did you find any errors in the procedures or illustrations?

m Yes

m No

If yes, what pages? _______________________________________________ Please explain: ___________________________________________________ _______________________________________________________________ Please include a copy of each page in question and mark your comments and suggestions.

Name: ________________________________ Phone: (_____) _____-_______ Company: _______________________________________________________ Address: ________________________________________________________ City: _________________________________ State: _______ Zip: _______ Position Title: ____________________________________________________

Thank You For Your Assistance Mack Trucks, Inc. (ATTENTION: RTS STAFF, 6S3)

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SERVICE PUBLICATIONS (RTS), 6S3 MACK TRUCKS INC WORLD HEADQUARTERS PO BOX M ALLENTOWN PA 18105-9972

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®

V-MAC II SERVICE MANUAL

JULY 1998 (REVISED)

© MACK TRUCKS, INC. 1998 ELECTRICAL 8-206

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ATTENTION The information in this manual is not all inclusive and cannot take into account all unique situations. Note that some illustrations are typical and may not reflect the exact arrangement of every component installed on a specific chassis.

The information, specifications, and illustrations in this publication are based on information that was current at the time of publication.

No part of this publication may be reproduced, stored in a retrieval system, or be transmitted in any form by any means including electronic, mechanical, photocopying, recording, or otherwise without prior written permission of Mack Trucks, Inc.

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SAFETY INFORMATION

SAFETY INFORMATION

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SAFETY INFORMATION Advisory Labels Cautionary signal words (Danger-Warning-Caution) may appear in various locations throughout this manual. Information accented by one of these signal words must be observed to minimize the risk of personal injury to service personnel, or the possibility of improper service methods which may damage the vehicle or render it unsafe. Additional Notes and Service Hints are utilized to emphasize areas of procedural importance and provide suggestions for ease of repair. The following definitions indicate the use of these advisory labels as they appear throughout the manual:

Directs attention to unsafe practices which could result in damage to equipment and possible subsequent personal injury or death if proper precautions are not taken.

Directs attention to unsafe practices which could result in personal injury or death if proper precautions are not taken.

Directs attention to unsafe practices and/or existing hazards which will result in personal injury or death if proper precautions are not taken.

An operating procedure, practice, condition, etc., which is essential to emphasize.

A helpful suggestion which will make it quicker and/or easier to perform a certain procedure, while possibly reducing overhaul cost.

000001a

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SAFETY INFORMATION Service Procedures and Tool Usage Anyone using a service procedure or tool not recommended in this manual must first satisfy himself thoroughly that neither his safety nor vehicle safety will be jeopardized by the service method he selects.

Individuals deviating in any manner from the instructions provided assume all risks of consequential personal injury or damage to equipment involved.

Also note that particular service procedures may require the use of a special tool(s) designed for a specific purpose. These special tools must be used in the manner described, whenever specified in the instructions.

1. Before starting a vehicle, always be seated in the driver’s seat, place the transmission in neutral, be sure that parking brakes are set, and disengage the clutch.

2. Before working on a vehicle, place the transmission in neutral, set the parking brakes, and block the wheels.

3. Before towing the vehicle, place the transmission in neutral and lift the rear wheels off the ground, or disconnect the driveline to avoid damage to the transmission during towing.

REMEMBER, SAFETY . . . IS NO ACCIDENT!

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NOTES

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INTRODUCTION

INTRODUCTION

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INTRODUCTION CHANGES FROM THE EXISTING V-MAC II SERVICE MANUAL Mack Trucks, Inc. has made many improvements to this V-MAC II® Service Manual, with changes to both content and organization.

This updated service manual now covers additional diagnostic blink codes including: r

1-8 — Starter input (high voltage)

r

5-7 — Driver alarm output (low voltage)

r

5-8 — Driver alarm output (high voltage)

r

5-9 — Fault lamp output (low voltage)

r

5-10 — Fault lamp output (high voltage)

r

6-5 — Battery voltage (low voltage)

The DESCRIPTION AND OPERATION section provides an overview of the V-MAC II system, as well as a brief description of each component.

The DIAGNOSTIC TOOLS AND PROCEDURES section outlines the diagnostic software and equipment that will be needed. It also provides troubleshooting procedures and service hints.

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The BLINK CODE DIAGNOSTICS section includes step-by-step procedures for troubleshooting diagnostic blink codes.

The SYMPTOM RELATED DIAGNOSTICS section provides the troubleshooting procedures for situations where there is no diagnostic blink code.

The REPAIR AND ADJUSTMENT PROCEDURES section guides the technician through connector repair, clutch switch adjustment, sensor adjustment and resetting low idle speed.

The SPECIFICATIONS section provides engine parameters, while the SPECIAL TOOLS section includes a listing of the necessary tools.

The SAE MESSAGE DESCRIPTIONS section provides a list of SAE/ATA serial line codes and corresponding descriptions.

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TABLE OF CONTENTS

TABLE OF CONTENTS

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TABLE OF CONTENTS SAFETY INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii DESCRIPTION AND OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 COMPONENT DESCRIPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 V-MAC II Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Fuel Injection Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Fuel Rack Actuator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 ECONOVANCE Timing Advance Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 SYSTEM SENSORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 RPM/TDC (Engine Position) Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 MPH (Road Speed) Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Timing Event Marker (TEM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Coolant Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Intake-Manifold Air Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Engine Oil Pressure Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Coolant Level Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Throttle Position Sensor (TPS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 CAB AND DASHBOARD SWITCHES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Speed Control Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Informational Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Shutdown Override Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Torque Limiting Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 SYSTEM LAMPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Electronic Malfunction Lamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Shutdown Indicator Lamp and Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 SYSTEM CONNECTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V-MAC II Module Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Fuel Injection Pump Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Serial Communication Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 31- and 23-Pin Bulkhead Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Sensor Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 MAJOR FUNCTIONS CHART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Fuel Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Timing Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Speed Control/Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Road Speed Limiting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Engine Protection Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Idle Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Accessory Relay Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 ON/OFF Fan Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 DIAGNOSTIC TOOLS & PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 DIAGNOSTIC SOFTWARE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Software Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 SAE/ATA Serial Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 DIAGNOSTIC TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Digital Multimeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Pro-Link 9000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 IBM-Compatible PC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 J 1708 Serial Data Link Adaptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 J 38500-63 Serial Link Jumper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

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TABLE OF CONTENTS DIAGNOSTIC BLINK CODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Determining Diagnostic Blink Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Diagnostic Blink Code Identification Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 TROUBLESHOOTING PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Determining That a Fault Exists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Locating Diagnostic Blink Code Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Performing Diagnostic Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 SERVICE HINTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Test Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Wire and Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 System Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 V-MAC II Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Engine Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 BLINK CODE DIAGNOSTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 DIAGNOSTIC BLINK CODE 1-1 OR 1-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 DIAGNOSTIC BLINK CODE 1-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 DIAGNOSTIC BLINK CODE 1-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 DIAGNOSTIC BLINK CODE 2-1 OR 2-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 DIAGNOSTIC BLINK CODE 2-3 OR 2-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 DIAGNOSTIC BLINK CODE 3-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 DIAGNOSTIC BLINK CODE 3-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 DIAGNOSTIC BLINK CODE 3-5, BASIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 DIAGNOSTIC BLINK CODE 3-5, ELECTRICAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 DIAGNOSTIC BLINK CODE 3-5, ADVANCED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 DIAGNOSTIC BLINK CODE 4-1, 4-2 OR 4-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 DIAGNOSTIC BLINK CODE 5-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111 DIAGNOSTIC BLINK CODE 5-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 DIAGNOSTIC BLINK CODE 5-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 DIAGNOSTIC BLINK CODE 5-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 DIAGNOSTIC BLINK CODE 5-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 DIAGNOSTIC BLINK CODE 5-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 DIAGNOSTIC BLINK CODE 5-7 OR 5-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 DIAGNOSTIC BLINK CODE 5-9 OR 5-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 DIAGNOSTIC BLINK CODE 6-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 DIAGNOSTIC BLINK CODE 6-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 DIAGNOSTIC BLINK CODE 7-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157 DIAGNOSTIC BLINK CODE 7-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 DIAGNOSTIC BLINK CODE 7-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 DIAGNOSTIC BLINK CODE 7-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172

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TABLE OF CONTENTS SYMPTOM RELATED DIAGNOSTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 BUFFERED MPH (SPEEDOMETER SIGNAL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 LOW COOLANT LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 INTERMITTENT PROBLEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182 LOW OIL PRESSURE WITH DRIVER ALARM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184 INCORRECT OIL PRESSURE VERSUS GAUGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186 INJECTION PUMP RPM (ENGINE SPEED) SENSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187 ENGINE BRAKE VERBAL COMPLAINT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188 BUFFERED RPM (TACH DRIVE OUTPUT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 ON/OFF FAN CONTROL VERBAL COMPLAINT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 SWITCH CIRCUIT DIAGNOSTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 SWITCH CIRCUIT FAILURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 SYMPTOM RELATED TROUBLESHOOTING CHART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 REPAIR AND ADJUSTMENT PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219 CONNECTOR REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 Deutsch Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 V-MAC II Module, Engine Oil Pressure, Intake Manifold Temperature, and Coolant Temperature Sensors and Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223 MPH, RPM/TDC, Throttle Position, TEM Sensors and Connectors and Bulkhead Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 TERMINAL REPLACEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 Using the J 35688 Crimping Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 Soldering Terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226 CLUTCH SWITCH ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 SENSOR ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 RPM/TDC Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 MPH Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 TEM Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 RESETTING LOW IDLE SPEED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 V-MAC I AND II E7 ENGINE PARAMETERS (1995 AND LATER) . . . . . . . . . . . . . . . . . . . . . . . . 232 SPECIAL TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233 TOOL LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234 SAE MESSAGE DESCRIPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235 COMMUNICATION STANDARDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236 INDEX. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243

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DESCRIPTION AND OPERATION

DESCRIPTION AND OPERATION

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DESCRIPTION AND OPERATION GENERAL INFORMATION

The following switches are used by the V-MAC II system:

The V-MAC II (Vehicle Management and Control) system is an electronic engine control system consisting of the following components:

r

Speed control ON/OFF switch

r

Combination SET/DECEL and RESUME/ ACCEL switch

r

Service brake switch

r

Parking brake switch

r

Clutch switch

r

PTO switches

r

Engine brake switch

r

Shutdown override switch

r

Torque limiting switch

r

V-MAC II module

r

Fuel injection pump

r

Fuel rack actuator

r

ECONOVANCEÂŽ

To enable V-MAC II to perform the necessary engine management and control functions, the following sensors provide information to the system: r

Oil pressure sensor

r

Intake-manifold air temperature sensor

r

Coolant temperature sensor

To alert the driver to possible problems with the vehicle, the V-MAC II system uses the following lamps:

r

MPH sensor

r

Electronic malfunction lamp

r

RPM/TDC (engine position) sensor

r

Shutdown lamp

r

Coolant level sensor

r

Timing Event Marker (TEM) sensor

r

Throttle position sensor

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DESCRIPTION AND OPERATION COMPONENT DESCRIPTIONS V-MAC II Module

The V-MAC II Module is mounted on a panel underneath the dashboard directly in front of the passenger seat.

Fuel Injection Pump The fuel injection pump is similar to previous production pumps using mechanical governors, and is located on the right side of the engine. On this pump, the mechanical governor is replaced by an actuator assembly.

Fuel Rack Actuator

Figure 1 — V-MAC II Module (CH Model Shown)

The fuel rack actuator, located on the rear of the pump, uses a proportional solenoid to provide positioning force. It works against a return spring to assure fuel shutoff if electric power is disconnected from the module. An increase in current flow moves the pump rack to a higher fuel delivery position. With a decrease in current flow, the return spring moves the rack to a lower fuel delivery position. The actuator incorporates a rack position sensor that supplies rack position information, via an electric signal, to the V-MAC II module to allow for control under all operating conditions.

The V-MAC II module is a microprocessor-based controller which provides a variety of functions including: r

Rack control

r

Fuel injection timing advance

r

Variable speed control

r

Cruise control

r

Road speed limiting

r

Engine protection

r

Engine shutdown

r

Idle shutdown

r

Speedometer and tachometer outputs

r

Diagnostic fault logging

r

Engine brake control

r

PTO operation

r

ON/OFF fan control

r

Theft deterrence

r

Maintenance information

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DESCRIPTION AND OPERATION ECONOVANCE Timing Advance Mechanism The ECONOVANCE timing advance mechanism serves as a part of the fuel injection pump drive and is located between the engine cylinder block and the injection pump. Timing is changed by rotating the injection pump camshaft relative to the engine crankshaft in response to a command from the V-MAC II module. The device has a helical spline machined into a sliding sleeve which is moved along the axis of rotation of the injection pump by engine lubricating oil. The delivery of the oil is controlled by an electrohydraulic actuator which converts the electrical output of the V-MAC II module into a proportionate rate of oil flow to the ECONOVANCE. The electrohydraulic ECONOVANCE actuator consists of two components in a single assembly, which is mounted on the top of the ECONOVANCE mechanism. The components are: Proportional solenoid —This type of solenoid has a core which can be moved smoothly to any position within its range of travel by varying the electric current it receives. The current is supplied and controlled by the V-MAC II module.

Hydraulic spool valve —The proportional solenoid sets the hydraulic spool valve at the position needed to control the flow of engine oil to the ECONOVANCE unit. The spool valve is not affected by the oil pressure being controlled.

SYSTEM SENSORS The V-MAC II module receives information via electrical signals from the sensors described in this section.

RPM/TDC (Engine Position) Sensor The RPM/TDC sensor is a speed sensor located in the flywheel housing. Speed sensors generate pulses of AC voltage through the principle of magnetic induction. When a conductor breaks through a magnetic field, a pulse of voltage is generated. The RPM/TDC sensor senses the passage of a series of notches machined in the forward face of the engine flywheel. These notches provide six pulses for each revolution of the engine crankshaft, spaced to occur at a fixed relationship to Top Dead Center (TDC) of each piston. The E9 flywheel uses eight notches which provide eight pulses for each engine revolution.

Engine revolutions per minute (rpm) is used as the primary parameter for determining the desired timing. This sensor also provides the crankshaft position information needed for comparison with the Timing Event Marker (TEM) information to calculate the current (actual) injection timing.

MPH (Road Speed) Sensor The miles per hour (mph) sensor is another speed sensor based on the principle of magnetic induction. It is mounted in the transmission output shaft housing, and senses the passage of a series of teeth on a tone wheel (toothed speedometer gear) mounted on the transmission output shaft. Vehicle speed is the primary parameter used for cruise control or road speed limiting modes.

Timing Event Marker (TEM)

Figure 2 — Proportional Solenoid (1) and Hydraulic Spool Valve (2)

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The Timing Event Marker (TEM), located at the outside rear of the injection pump, is similar to the road speed and engine position sensors. It senses the passage of the timing finger in the injection pump rack actuator, which is adjusted to occur at port closure of the No. 1 plunger during injection pump calibration. The timing finger is also used to orient the injection pump camshaft as the pump is installed on the engine, and to set the initial injection timing.

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DESCRIPTION AND OPERATION Coolant Temperature Sensor The coolant temperature sensor is usually located in the rear of the water manifold. It monitors the temperature of the engine coolant to allow evaluation of operating conditions that cause high coolant temperatures (e.g., radiator blockage, thermostat failure, heavy load, high ambient temperatures, etc.). This sensor is also used to assist in cold start conditions.

Intake-Manifold Air Temperature Sensor The intake-manifold air temperature sensor, located in the intake manifold, is used for accurate air/fuel ratio calculation. This information is also used for engine timing control, to prevent the formation of white smoke during engine warm-up and to prevent misfire under light load conditions.

CAB AND DASHBOARD SWITCHES Speed Control Switches The speed control switches provide input from the driver to set the modes or command speeds for the speed control functions. These switches are located on the dashboard. r

Speed control ON/OFF switch

r

Combination SET/DECEL and RESUME/ ACCEL switch

Informational Switches The V-MAC II system receives operating information from the following switches: r

Service brake switch, located in-line within the brake system

r

Parking brake switch, located in-line in the parking brake circuit

The engine oil pressure sensor, located on top of the oil filter assembly, monitors the engine oil pressure to warn of lubrication system failure.

r

Clutch switch, located under the dashboard above the clutch pedal

r

PTO switches, located on the dashboard

Coolant Level Sensor

r

Engine brake switch, located on the dashboard

The coolant level sensor is located on the rear of the radiator near the bottom of the upper coolant tank. It monitors the level of coolant in the radiator to warn of coolant loss.

The driver activates these switches by applying the brakes, disengaging the clutch, or engaging the PTOs or engine brake.

Engine Oil Pressure Sensor

Throttle Position Sensor (TPS) The Throttle Position Sensor (TPS), located on the side of the accelerator pedal assembly, replaces the mechanical linkage for fuel control with an electric sensor. The “drive by wire� pedal is designed to provide a system that feels similar to the standard type of pedal and mechanical linkage, but with reduced sensitivity to chassis motion for improved driver control. This sensor provides driver fuel requirement input to the V-MAC II module.

Shutdown Override Switch The shutdown override switch, located on the dashboard, allows a short period (30 seconds) of operation after the engine has been shut down due to a problem detected by the V-MAC II system. This enables the driver to move the vehicle, if necessary.

Torque Limiting Switch The torque limiting switch (not available on all vehicles) is located in the transmission. It protects driveline components by reducing engine torque when it senses that the transmission is in a very low gear.

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DESCRIPTION AND OPERATION SYSTEM LAMPS Electronic Malfunction Lamp

The electronic malfunction lamp also provides blink codes for system diagnostics. For an explanation of blink code activation and interpretation refer to the Blink Code Identification chart in the DIAGNOSTIC TOOLS AND PROCEDURES section.

Shutdown Indicator Lamp and Alarm

Figure 3 — Electronic Malfunction Lamp

The electronic malfunction lamp is located on the dashboard. It is amber in color and its function is to alert the driver to an electrical problem with the V-MAC II system.

Figure 4 — Shutdown Indicator Lamp

The V-MAC II system performs a self-test each time the vehicle is started. The electronic malfunction lamp remains ON while this test is being carried out. After the self-test is completed, the lamp will turn OFF and remain OFF, unless a problem is detected.

The engine cannot be started until the two second system check is completed.

If the electronic malfunction lamp turns ON while driving the vehicle, the V-MAC II system has detected a problem.

In most circumstances the vehicle will operate when the lamp is ON, although engine performance may be affected.

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The red shutdown indicator lamp, located on the dashboard, will turn ON under any of the following conditions: r

Coolant level is below the minimum level

r

Oil pressure is below the minimum level

r

Engine temperature exceeds the maximum

In addition to the shutdown indicator lamp, V-MAC II also provides an audible alarm (referred to as the driver alarm). Like the electronic malfunction lamp, the shutdown lamp and driver alarm operate during the self-test and turn OFF when the test is completed. The shutdown indicator lamp and driver alarm will also turn ON when the system detects a problem which warrants shutting down the engine.

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DESCRIPTION AND OPERATION SYSTEM CONNECTORS The V-MAC II system receives data from a variety of sensors located throughout the vehicle. Sensor connectors serve as a major component of this system by providing a connection between the sensors and the V-MAC II module. This section describes all of the connectors used in the V-MAC II system.

V-MAC II Module Connectors There are three connectors between the main harness and the V-MAC II module. The J1A and J1B connectors are both 30-pin connectors, while the J2 connector is an 18-pin connector. Each pin on the harness connectors is marked along the outside edge of the connector. Each of the three harness connectors have 3 columns labeled 1, 2 and 3. The rows for these connectors are labeled as follows: r

J1A: rows A–K

r

J1B: rows L–Y.

r

J2: rows A –F.

Figure 5 — J1A, J1B and J2 Module Connectors

To remove any connector from the V-MAC II module, loosen the hex nut in the center of the connector and gently pull the connector from the module. For easy reference, the previous illustration shows each pin number as it appears on the harness connector. Be sure that the connector is aligned as shown below to avoid confusion when checking pin numbers.

The following is a graphic depiction of the V-MAC II module inputs and outputs.

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DESCRIPTION AND OPERATION

Figure 6 — V-MAC II Module Inputs and Outputs

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DESCRIPTION AND OPERATION The following tables list connector pin numbers and corresponding signal descriptions.

J1A CONNECTOR

J1B CONNECTOR

Pin Number

Description

Pin Number

Description

A1

Timing solenoid PLUS (+) line

L1

TPS signal (+) line

A2

Fuel rack actuator MINUS (−) line

L2

TPS voltage reference (+) line

A3

Timing solenoid MINUS (−) line

L3

TPS ground (−) line

B1

Fuel rack actuator PLUS (+) line

M1

Not used

B2

Fuel rack actuator PLUS (+) line

M2

Not used

B3

Fuel rack actuator MINUS (−) line

M3

Key switch

C1

Not used

N1

PLUS (+) 12 volts from battery

C2

Not used

N2

PLUS (+) 12 volts from battery

C3

Not used

N3

PLUS (+) 12 volts from battery

D1

Not used

P1

Chassis ground

D2

Not used

P2

Chassis ground

D3

Intake manifold temperature signal (+) line

P3

Engine brake relay control line

R1

E1

Coolant temperature (+) line

Shutdown lamp and alarm signal (+) line

E2

Coolant temperature (−) line

R2

E3

Intake manifold temperature signal (+) line

Electronic malfunction lamp signal (+) line

R3

Accessory relay control line

F1

Not used

S1

J 1922 data line A PLUS (+) line

F2

Oil pressure signal (+) line

S2

J 1587 serial data line A PLUS (+) line

F3

Coolant level signal (+) line

S3

Not used

G1

Sensor power (+) line

T1

J 1922 data line B MINUS (−) line

G2

Sensor ground (−) line

T2

J 1587 serial data line B MINUS (−) line

G3

MPH sensor PLUS (+) line

T3

Not used

H1

RPM/TDC PLUS (+) line

W1

Not used

H2

RPM/TDC MINUS (−) line

W2

H3

MPH sensor PLUS (+) line

Buffered RPM out line (speedometer signal)

J1

TEM PLUS (+) line

W3

Buffered RPM out line (tachometer signal)

J2

TEM MINUS (−) line

X1

Not used

J3

Rack position sensor signal (+) line

X2

Not used

K1

Rack position sensor signal (+) line

X3

Not used

K2

Rack position sensor signal (+) line

Y1

Fan clutch control

K3

Not used

Y2

Auxiliary No. 1 out line

Y3

Not used

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DESCRIPTION AND OPERATION J2 CONNECTOR Pin Number

Description

A1

Not used

A2

Not used

A3

Starter signal (+) line

B1

Not used

B2

Service brake signal (+) line

B3

Parking brake signal (+) line

C1

Clutch engaged signal (+) line

C2

Speed control SET/DECEL signal (+) line

C3

Speed control ON/OFF switch signal (+) line

D1

Speed control RESUME/ACCEL signal (+) line

D2

Shutdown override signal (+) line

D3

PTO 1 selected signal (+) line

E1

PTO 2 selected signal (+) line

E2

Torque limit switch signal (+) line

E3

Not used

F1

Not used

F2

Chassis ground

F3

Not used

Fuel Injection Pump Connector

Figure 7 — Fuel Injection Pump Connector

On V-MAC II vehicles, the engine harness connects to the fuel injection pump via an injection pump connector harness which is integral to the pump governor housing. The harness provides easy access to the injection pump electrical pins.

The harness uses a Deutsch connector similar in appearance and function to the serial communication port connector located under the dashboard. The connector has a rotating locking collar which must be locked in place. A definite click can be felt when the collar is properly locked in place. The mating connector on the engine harness has also been changed to a Deutsch connector.

The harness is an integral part of the governor cover and cannot be removed for repairs.

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DESCRIPTION AND OPERATION Serial Communication Port The serial communication port is a 6-pin connector used for system diagnostics and reprogramming. It is located under the dashboard to the left of the steering column. This port is used for connecting the Pro-Link 9000® hand held-reader or the diagnostic computer. Following the illustration is a list of pin letters and designations.

31- and 23-Pin Bulkhead Connectors Like the fuel injection pump connector, the bulkhead connectors have a rotating locking collar which must be locked in place. A definite click can be felt when the collar is properly locked in place. For a list of pin designations, refer to the appropriate electrical manual.

Bulkhead connector terminals are removed and installed in basically the same manner as the communication and pump harness connectors.

Follow the instructions for terminal removal and replacement in the Connector Repair section.

Sensor Connectors The oil pressure sensor connector is a three-pin connector which plugs directly into the sensor.

For reference, the pins are designated by letter.

Figure 8 — Serial Communication Port Connector

Pin Letter

Designation

A

Serial data link PLUS (+) line

B

Serial data link MINUS (−) line

C

PLUS (+) 12 volts

D

Accessory relay

E

Chassis ground

F

Not used

Figure 9 — Oil Pressure Sensor Connector

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DESCRIPTION AND OPERATION The intake-manifold air temperature sensor and the coolant temperature sensor both use a two-pin connector which plugs directly into the sensor. For reference, the pins are designated by letter.

The throttle position sensor uses a two-part, three-pin connector. The For reference, pins are designated by letter.

Figure 12 — Throttle Position Sensor Connector Figure 10 — Intake-Manifold Air Temperature and Coolant Temperature Sensor Connector

The MPH sensor, RPM/TDC sensor, timing actuator sensor, coolant level sensor and Timing Event Marker (TEM) sensor each use a two-part, two-pin connector. For reference, the pins are designated by letter.

Figure 11 — MPH, RPM/TDC, Timing Actuator, Coolant Level and TEM Sensor Connector

Page 12

The remaining system connectors are spade-type connectors. They are used for speed control, park and service brake, PTO and engine brake switches.

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DESCRIPTION AND OPERATION MAJOR FUNCTIONS CHART Fuel Control Inputs

Backup

Effects If Input Fails

Blink Code

Throttle position sensor:

None

r Low idle speed increases to 900 rpm.

5-1

r Isochronous governor (controls to 900 rpm).

5-2

r Signal line open, short to ground or short to voltage

r VSC and cruise control still work.

r Reference line open or grounded

r All of the above at a throttle position greater than 0%.

r Reference line shorted to 12 volts RPM/TDC sensor

TEM sensor

r Rough running at low and high idle speeds.

3-2

r Rough running VSC. r Correct RPM reading on diagnostic tools. r Engine stall, if both sensors fail TEM sensor

RPM/TDC sensor

r Smooth transition to backup.

3-4

r Correct RPM reading on diagnostic tools. r Engine stall, if both sensors fail.

Rack position sensor

None

r Open, short to ground or short to voltage

r Rack actuator shutdown (until electrical problem is resolved).

7-5 7-6 7-7

Intake-manifold air temperature sensor

None

Coolant temperature sensor

None

r Fault displayed by PC or Pro-Link.

2-3 2-4

r Fault displayed by PC or Pro-Link.

2-1 2-2

Ignition key switch

None

r If the switch turns OFF or fails open, the fuel turns OFF immediately. r If the switch fails closed, the engine will not stop with the key.

Starter input

RPM/TDC sensor Throttle position sensor

r Cannot achieve start fuel unless RPM signal indicates starting speed, or 100% throttle position is achieved.

1-8

Timing Control Inputs

Backup

Effects If Input Fails

Blink Code

RPM/TDC sensor

TEM sensor

r Full retard commanded.

3-2

r Full retard assumed.

TEM sensor

RPM/TDC sensor

r Full retard commanded.

3-4

r Full retard assumed.

Intake-manifold air temperature sensor Coolant temperature sensor

None

r Light load timing retarded. r Possible white smoke.

None

2-3 2-4

r Light load timing retarded.

2-1

r Possible white smoke.

2-2

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DESCRIPTION AND OPERATION Speed Control/Cruise Control Inputs

Backup

Effects If Input Fails

Blink Code

Speed control switches:

None

r Cannot set speed control.

3-2

r Cannot set or resume speed control.

r ON/OFF r SET/RESUME Throttle position sensor

None

See “Fuel Control” chart.

5-1 5-2

MPH sensor

RPM/TDC sensor

None

TEM sensor

r Speed control functions (cruise control, VSC, SSC) are canceled.

4-1

r No speedometer output.

4-2

r Reduced power (customer selectable).

4-3

r VSC/SSC will drop out.

3-4

r Full retard commanded. r Full retard assumed. r Engine stall, if both sensors fail.

Clutch switch

None

r If the switch is closed, speed control will not function. r If the switch is open, speed control will not cancel.

Service brake switch

None

r If the switch is closed, speed control will not function. r If the switch is goes from open to closed with the parking brake OFF, VSC/SSC will not function.

Parking brake switch

None

r If the switch is closed, speed control will not function. r If the switch is goes from open to closed, VSC/SSC will not function.

PTO switches 1 and 2

None

r If the switches are open, cannot set SSC. r If the switches are closed, engine speed will be limited.

Road Speed Limiting Inputs

Backup

Effects If Input Fails

Blink Code

MPH sensor

None

r Reduced power (customer selectable).

4-1

r No speedometer output.

4-2 4-3

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DESCRIPTION AND OPERATION Engine Protection Shutdown Inputs

Backup

Effects If Input Fails

Blink Code

Oil pressure sensor

None

r Protection/shutdown inactive for oil pressure.

1-1 1-2

Coolant temperature sensor

Coolant level sensor

None

None

r Protection/shutdown inactive for coolant temperature.

2-1

r Open sensor indicates low level.

1-7

2-2

r Harness open/short could cause protection/ shutdown, or make protection/shutdown inactive for coolant level.

None

r Override cannot be performed.

Inputs

Backup

Effects If Input Fails

Blink Code

TPS sensor

None

r If vehicle is not moving, shutdown will occur at proper time.

5-1

Shutdown override switch

Idle Shutdown

Shutdown override switch

None

r Override cannot be performed.

MPH sensor

None

r Idle shutdown will occur if the accelerator pedal position is constant, even if the vehicle is moving.

5-2

4-1 4-2 4-3

Coolant temperature sensor

None

r Shutdown occurs after the warm-up and shutdown times have expired, even if the engine has not yet reached the warm-up temperature.

2-1

Blink Code

2-2

Accessory Relay Control Inputs

Backup

Effects If Input Fails

Key switch

None

r If switch turns OFF or fails, the relay turns OFF 3 seconds later.

Starter input

None

r If switch signal is lost, the system will not reset after a shutdown by engaging the starter — cycle the power instead.

Inputs

Backup

Effects If Input Fails

Coolant temperature sensor

None

r Fan will be engaged all of the time.

12-volt supply

None

r Loss of 12 volts engages the fan.

ON/OFF Fan Control Blink Code

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NOTES

Page 16

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DIAGNOSTIC TOOLS & PROCEDURES

DIAGNOSTIC TOOLS & PROCEDURES

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DIAGNOSTIC TOOLS & PROCEDURES DIAGNOSTIC SOFTWARE The V-MAC II module contains a variety of standard integrated software packages which allow for detection, logging and retrieval of diagnostic information about the V-MAC II system.

Diagnostic software is an integral part of the system. Its purpose is to aid in troubleshooting the V-MAC II system while providing increased safety by constantly checking the hardware. The diagnostic software monitors all inputs and detects those that are out of the allowable ranges or in invalid states.

Software Functions When an unusual condition is detected, the V-MAC II software begins a timer. If the condition does not clear within a specified period of time (known as the fault recognition period), a fault is logged. Fault recognition periods have been set according to the safety requirements of the sensor. These time periods have been specified to avoid reporting false faults, while maintaining engine and vehicle safety.

In the event of a circuit failure, a default value will be reported. This default value will allow the engine or vehicle to operate even though the V-MAC II module does not have any information from the failed circuit.

4. The V-MAC II module will update the fault table in its internal memory. The fault table contains a record of how many times the failure has occurred. The occurrence count is limited to 15, and the stored codes will remain in memory until cleared by a diagnostic computer, or until the information is no longer useful for diagnostic purposes.

All of the faults logged by the V-MAC II system are recoverable. This means that if the unusual condition returns to normal for a continuous period of time, the fault will be cleared and the fault lamp will go OFF. However, the occurrence will be logged in the fault table to aid in future troubleshooting.

After a failure is detected, the diagnostic software will perform the following functions:

SAE/ATA Serial Line 1. The electronic malfunction lamp, located on the dashboard, will go ON. This lamp will remain ON for active faults, and go OFF when there are no longer any active faults present in the system.

2. A fault message will be sent in a standard format on the SAE/ATA serial line to alert other devices of this failure. A similar message will be transmitted when the failure is cleared.

3. The data normally transmitted on the SAE/ATA serial line for this sensor will be replaced with a “Bad Data” indicator. This will signal the other devices on the serial line to ignore the data for this sensor.

The V-MAC II diagnostic software is closely tied to the SAE/ATA serial line. This provides an easy means of troubleshooting the system, since a complete fault history can be retrieved from the SAE/ATA serial line with a diagnostic tool such as the Pro-Link 9000 or a diagnostic PC.

When a problem occurs in the SAE/ATA J 1708 serial line, the Pro-Link 9000 and the diagnostic PC may not be able to read the information from the vehicle. The fault lamp will be ON, and the dash switches will have to be used to read the blink codes. The Pro-Link will display the message “No Data Received.”

For SAE/ATA standard terminology, refer to the SAE Message Descriptions section.

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DIAGNOSTIC TOOLS & PROCEDURES DIAGNOSTIC TOOLS

Figure 13 — Interface Devices

To utilize the diagnostic capabilities of the V-MAC II system, several diagnostic tools are available: r

Digital multimeter

r

Pro-Link 9000®

r

IBM®-compatible PC

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DIAGNOSTIC TOOLS & PROCEDURES Digital Multimeter

Pro-Link 9000

The digital multimeter is used to make the required measurements when performing diagnostic testing procedures such as measuring voltage and resistance, checking for short circuits and checking for open circuits.

Since there are varying types of digital multimeters available, this manual does not provide specific instructions. Refer to the instructions provided with your multimeter.

For consistent, successful diagnostic test results, it is essential to understand the following terms: Voltage (volts) — The electric potential or potential difference, expressed in volts.

Resistance (ohms) — The amount of opposition offered by a component to the passage of a steady, electric current through that component, expressed in ohms.

Continuity (ohms) — Very little or no resistance, indicating that a complete pathway for the current flow exists.

Whenever a diagnostic procedure prompts you to perform a continuity check, be sure to use the continuity feature of your multimeter. Refer to the appropriate multimeter instructions for operating procedures.

Current (amps) — The strength of the flow of electricity, expressed in amps.

Short Circuit (short) — A connection of comparatively low resistance, accidentally or intentionally made, between points on a circuit where the resistance is normally much greater.

Open Circuit (open) — Any situation where the normally closed or continuous flow of electricity has been interrupted (e.g., a broken wire in the wiring harness).

Page 20

Figure 14 — Pro-Link 9000

The Pro-Link 9000 is a hand-held device which connects to the serial communication port, located under the dashboard to the left of the steering column. This unit may be used for the following functions: r

Display all active faults.

r

Display all occurrences of inactive faults.

r

Monitor selected system parameters.

r

Clear stored fault codes.

r

Reset low idle speed.

r

Reprogram customer data.

To use the Pro-Link 9000, follow the instructions provided with the unit.

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DIAGNOSTIC TOOLS & PROCEDURES IBM-Compatible PC

J 1708 Serial Data Link Adaptor The personal computer communicates with the vehicle via the J 1708 serial data link adaptor.

The Pro-Link or the J 38351 (B) serial link adaptor can be used as an interface in place of this adaptor.

J 38500-63 Serial Link Jumper

Figure 15 — Typical Laptop Computer

The Personal Computer (PC) is the most advanced diagnostic tool available for troubleshooting the V-MAC II system. In addition to performing all the functions of the Pro-Link 9000, it allows enhanced system diagnostics.

The personal computer also permits information specific to the vehicle to be entered and stored in the V-MAC II module’s internal memory, and provides more flexibility in password selection.

Any 100% IBM-compatible computer will work with the system. In order to connect a computer to the vehicle, a serial link interface is required.

The ATA serial link adapter (part No. J 38351 or J 38351-B) or the Pro-Link 9000 can be used as the interface device.

In addition, the V-MAC II SERVICE DIAGNOSTICS software package MUST BE loaded. This software package, as well as complete instructions for installing and running the program, is available through your MACK distributor. Be sure to follow the instructions completely.

Figure 16 — Serial Link Jumper

The J 38500-63 serial link jumper should be used with both the J 1708 Serial data link adaptor and the Pro-Link. The jumper provides the ability to turn the V-MAC II system ON without having to turn on the key. This is not only convenient for programming, but is also very important for diagnostic troubleshooting.

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DIAGNOSTIC TOOLS & PROCEDURES If you do not have a jumper and the diagnostic procedure requires that you Connect the serial link jumper into the serial communication port, there are two alternative solutions:

5. Immediately after the idle time, the V-MAC II module will begin to flash a two-digit blink code. The two digits of the code will be separated by a one-second idle time.

r

Serial Communication Port — Connect a wire from pin C of the serial communication port to pin D of the port.

r

Accessory Relay Jumper — Disconnect the white 16-gauge wire on the accessory relay post B, which leads to the V-MAC II module.

Then connect a jumper wire from the electrical equipment panel post, marked BATTERY, to the accessory relay post B. The accessory relay should pull in.

6. Each digit of the blink code may consist of up to eight flashes. Both the ON and OFF time for each flash will be one-fourth of a second.

DIAGNOSTIC BLINK CODES Determining Diagnostic Blink Codes The V-MAC II module is capable of blinking a twodigit blink code for each of the active faults in the V-MAC II system. These codes are displayed on the electronic malfunction lamp, located on the dashboard. The diagnostic blink code allows the technician to diagnose an active fault in the system without using an expensive diagnostic tool such as the Pro-Link 9000 or PC. Diagnostic blink codes can be used for isolating and troubleshooting any active faults in the V-MAC II system.

To properly activate and use the blink codes, follow the steps below.

7. Count the ON flashes of the fault lamp in order to determine the two-digit blink code.

8. When there are multiple active faults present in the system, display of each fault must be requested separately, since only one active fault can be blinked per request. To request that another fault be displayed, hold in the SET/DECEL or RESUME/ACCEL switch until the fault lamp goes OFF. The blink code sequence for the next fault will begin after the one-second idle time.

Remember that there will be a one-second idle time between the two digits of the code.

If the request for display of a fault is repeated while V-MAC is already blinking an active fault, the current blink code sequence will stop and the blink code sequence for the next active fault will be displayed.

1. Turn the ignition key to the ON position and wait while the system performs its twosecond self test.

2. If the electronic malfunction lamp remains ON after the self test is completed, there is an active fault.

3. With the speed control ON/OFF switch in the OFF position, press and hold the SET/ DECEL or the RESUME/ACCEL switch until the fault lamp goes OFF. 4. The fault lamp will remain OFF for approximately 1 second. The period of time during which the fault lamp is OFF will be referred to as an idle time.

Page 22

If an active fault is cleared while V-MAC is blinking that fault, the procedure will not stop.

After every complete blinking sequence, the fault lamp will return to normal functions. It will remain ON for active faults and OFF for inactive faults.

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DIAGNOSTIC TOOLS & PROCEDURES

If more than one active fault is present, continue the blink code sequence until the first active fault is displayed again to be sure all faults have been recovered.

The V-MAC II blink code software will not provide codes for inactive faults. To access this data, use the Pro-Link 9000 or PC. The next section includes a list of possible blink codes.

Diagnostic Blink Code Identification Chart The following table lists the possible faults which may occur in the V-MAC II system. After obtaining the active fault code sequence, find the code in the table to determine where to begin troubleshooting procedures. Then turn to the page listed in the Table of Contents or Index for the appropriate diagnostic test section.

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DIAGNOSTIC TOOLS & PROCEDURES Blink Code

Protocol PID

SID

Assignment Listing

Failure

MID

FMI

1-1

100

4

Engine oil pressure

Voltage below normal or shorted low

142

1-2

100

3

Engine oil pressure

Voltage above normal or shorted high

142

1-7

111

3

Engine coolant level

Voltage above normal or shorted high

142

3

Starter input

Voltage above normal or shorted high

142

1-8

237

2-1

110

4

Engine coolant temperature

Voltage below normal or shorted low

142

2-2

110

3

Engine coolant temperature

Voltage above normal or shorted high

142

2-3

105

4

Intake-manifold air temperature

Voltage below normal or shorted low

142

2-4

105

3

Intake-manifold air temperature

Voltage above normal or shorted high

142

3-2

190

2

RPM/TDC (engine position)

Data erratic, intermittent or incorrect

142

3-4

1

2

Timing Event Marker (TEM) sensor

Data erratic, intermittent or incorrect

142

3-5

2

7

Timing actuator

Mechanical system not responding properly, or out of adjustment

142

4-1

84

4

MPH (road speed) sensor

Voltage below normal or shorted low

142

4-2

84

3

MPH (road speed) sensor

Voltage above normal or shorted high

142

4-3

84

8

MPH (road speed) sensor

Abnormal frequency, pulse width or period

142

5-1

91

4

Throttle Position Sensor (TPS)

Voltage below normal or shorted low

142

5-2

91

3

Throttle Position Sensor (TPS)

Voltage above normal or shorted high

142

5-3

4

5

Rack actuator

Current below normal or open circuit

142

5-4

4

7

Rack actuator

Mechanical system not responding properly, or out of adjustment

142

5-5

4

6

Rack actuator

Current above normal or grounded circuit

142

5-6

4

11

Rack actuator

Failure mode not identifiable

142

5-7

238

4

Driver alarm output

Voltage below normal or shorted low

142

5-8

238

3

Driver alarm output

Voltage above normal or shorted high

142

5-9

239

4

Fault lamp output

Voltage below normal or shorted low

142

5-10

239

3

Fault lamp output

Voltage above normal or shorted high

142

1

Battery voltage

Data valid but voltage below normal or shorted low

142

6-5

168

6-6

254

12

Internal module communications

Bad intelligent device or component

142

7-1

246

4

Brake pedal switch No. 1 (service brake)

Voltage below normal or shorted low

142

7-5

3

5

Rack position sensor

Current below normal or open circuit

142

7-6

3

6

Rack position sensor

Current above normal or grounded circuit

142

7-7

11

Rack position sensor

Failure mode not identifiable

142

Red light and alarm

110

0

Engine coolant temperature

Data valid but above normal operating range

142

Red light and alarm

100

1

Engine oil pressure

Data valid but below normal operating range

142

Page 24

3

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DIAGNOSTIC TOOLS & PROCEDURES TROUBLESHOOTING PROCEDURES Determining That a Fault Exists Before beginning any troubleshooting procedure, be certain that a problem actually exists. If possible, talk to the driver or the person who noticed the problem, and try to obtain as much information as possible. In some cases, the only evidence of a fault is a verbal complaint.

After determining that an active fault does exist, follow the troubleshooting sequence listed in this manual. The procedures are organized according to the diagnostic code.

Locating Diagnostic Blink Code Information Once the diagnostic code has been displayed, there are several places to find information explaining what the diagnostic code actually means. r

Table of Contents (front of the book)

r

Index (back of the book)

Performing Diagnostic Tests Once a fault has been logged, whether active or inactive, the tests for that particular fault must be completed, step by step, in the order in which they are listed. This allows you to logically move toward a solution to the problem. r

Follow the tests exactly as they are outlined.

r

Start at the beginning of each sequence, and perform each test in the order in which it is outlined.

r

Do not skip steps or attempt to shortcut the test procedure.

r

The results of each test will identify possible causes of the problem, or will determine which test to perform next.

Not all tests are performed in sequence. For example, the results of a particular test may specify performing Test 9 after Test 4, skipping Tests 5–8.

These sources list the pages that contain information on a particular diagnostic code.

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DIAGNOSTIC TOOLS & PROCEDURES SERVICE HINTS Following the recommendations discussed in this section may save considerable time and effort when performing diagnostic procedures.

Before conducting a continuity check, as required in several test procedures, the ignition key must be in the OFF position.

Test Procedures When instructed in a test procedure to check continuity or voltage from one pin to each of the others, this means one at a time, not all at the same time.

When inserting a test probe into a connector, do not force the probe into the connector. Doing so can damage to the connector.

If instructed to disconnect the harness connector from the V-MAC II module during any of the test procedures, the ignition key must be in the OFF position, and the accessory relay must be OFF (make sure the serial link jumper is not installed).

Failure to observe this caution can cause internal electrical damage to the module.

Figure 17 — Ignition Key Position for Continuity Check

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DIAGNOSTIC TOOLS & PROCEDURES Wire and Connectors

When performing electrical diagnostic tests, it is always a good practice to move (wiggle) the electrical wires and connectors. This will help identify the instances where wires are making poor or intermittent contact. When working with the V-MAC II system, this may cause a fault to be logged, which will help to identify the problem.

In any test procedure that requires disconnecting a connector, visually inspect both sides of the connector for debris, broken, bent or missing pins, or broken connector housings.

Many electrical problems are caused by dirty, loose or disconnected connectors. Intermittent problems usually indicate a loose or poor connection, or marginal adjustment on a component. Before beginning any test sequence: r

Check the condition of the wires and connectors.

r

Check the batteries for correct voltage.

r

Examine each harness for places where sharp metal edges may have cut through.

r

Check for damaged connectors or wires which may have pulled out of connector terminals.

r

Inspect seals on the connectors for looseness, cracks, missing parts, etc.

r

Make sure there is no grease on the connectors. If any grease is found, it should be cleaned off, as improper sealing can cause failures.

The design of MACK wiring harnesses allows individual wire repair or replacement.

Replacement of a wiring harness should only be necessary when major damage has occurred to the harness.

System Components Before replacing components, retest the circuit to confirm that an active fault still exists. Unless otherwise specified, “replace� means to install a new component.

V-MAC II Module

The least likely component to fail is the V-MAC II module.

In any diagnostic test procedure where the instructions call for replacing the V-MAC II module, do not reprogram the replacement module until you are certain that the problem has been solved. If replacing the module does solve the problem, it is essential that the module is programmed with the vehicle operating parameters. Failure to program the replacement module will result in reduced system performance. To program the module with vehicle and customer data, follow the instructions which are supplied with the Pro-Link 9000 or the PC diagnostic software package. It is essential that the module be reprogrammed with the MACK DATA PROGRAMMING software (see your MACK distributor). Do not program a replacement V-MAC II module with MACK DATA PROGRAMMING until it is confirmed that the new V-MAC II module has corrected the problem.

Reprogramming with MACK DATA PROGRAMMING executes the password protection function which assigns a new password to the vehicle. This process is irreversible. If the old module is not the problem and it is reinstalled on the vehicle, it cannot be reprogrammed because the password will no longer match.

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DIAGNOSTIC TOOLS & PROCEDURES Engine Shutdown

If the engine shuts down, check the following before calling for service. r

Is the electronic fault lamp on? If so, determine the blink code and call for service.

r

Is the engine shutdown lamp on after the engine has shut down? If so, the coolant level is low or the coolant temperature is too high.

r

Does the engine start? If so, the shutdown was probably due to Idle Shutdown. If the engine shutdown lamp comes on, check for low oil pressure. If the oil pressure is low, TURN OFF THE ENGINE IMMEDIATELY!

r

If the engine does not start, check for low fuel level.

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BLINK CODE DIAGNOSTICS

BLINK CODE DIAGNOSTICS

Page 29

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DIAGNOSTIC CODE 1-1 OR 1-2 DIAGNOSTIC BLINK CODE 1-1 OR 1-2 ENGINE OIL PRESSURE SENSOR TESTS DIAGNOSTIC CODE 1-1 OR 1-2

Figure 18 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

1-1

1-2

PID

100

100

4

3

SID FMI MID

142

142

Name

Engine Oil Pressure

Engine Oil Pressure

Failure

Voltage below normal or shorted low

Voltage above normal or shorted high

Page 30

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DIAGNOSTIC CODE 1-1 OR 1-2 Test 1

Test 2

Checking for proper voltage on the voltage reference (+) line

Checking for voltage on the ground (−) line

Figure 20 — Voltage from Pin A to Ground Figure 19 — Voltage from Pin B to Ground

1. Disconnect the harness from the oil pressure sensor.

2. Turn the ignition key to the ON position.

3. Measure the voltage from harness connector pin B (the voltage reference [+] line) to a good ground.

1. Measure the voltage from harness connector pin A (the ground [−] line) to a good ground.

If the voltage is greater than 0.5 volts, proceed to Test 5.

If the voltage is less than 0.5 volts, proceed to Test 4.

If the voltage is between 4.75 and 5.25 volts, proceed to Test 2.

Test 3

If the voltage is not between 4.75 and 5.25 volts, proceed to Test 3.

Checking the voltage reference (+) line, high or low

If the voltage in Test 1 was greater than 5.25 volts, proceed to Test 6.

If the voltage in Test 1 was less than 4.75 volts, proceed to Test 7.

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DIAGNOSTIC CODE 1-1 OR 1-2 Test 4

Test 5

Checking for stray voltage on the signal (+) line

Checking for voltage in the harness on the sensor ground (−) line

Figure 22 — Voltage from Pin G2 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A and J1B connectors from the V-MAC II module.

Figure 21 — Voltage from Pin C to Ground

1. Measure the voltage from harness connector pin C (the signal [+] line) to a good ground.

If voltage is greater than 0.5 volts, proceed to Test 9.

If the voltage is less than 0.5 volts, proceed to Test 8.

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1A connector pin G2 (the sensor ground [−] line) to a good ground.

If the voltage is greater than 0.5 volts, locate and repair the short on the sensor ground (−) line in the harness. Replace the V-MAC II module and the oil pressure sensor. Retest to be sure the problem has been corrected.

If the voltage is less than 0.5 volts, replace the V-MAC II module and the oil pressure sensor.

Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 1-1 OR 1-2 Test 6

Test 7

Checking for stray voltage in the sensor power (+) line

Checking for continuity in the harness

Figure 23 — Voltage from Pin G1 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A and J1B connectors from the V-MAC II module.

Figure 24 — Jumper between Pins B and C

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1A connector pin G1 (the sensor power [+] line) to a good ground.

If the voltage is greater than 5 volts, locate and repair the short to power. Replace the oil pressure sensor. Retest to be sure the problem has been corrected.

If the voltage is less than 5 volts, proceed to Test 12.

Figure 25 — Continuity between Pins G1 and F2

1. Turn the ignition key to the OFF position.

2. Connect a jumper between harness connector pins B and C. 3. Disconnect the J1A connector from the V-MAC II module.

4. Check for continuity between J1A connector pins G1 (the sensor power [+] line) and F2 (the oil pressure signal [+] line).

If there is continuity, proceed to Test 14.

If there is no continuity, locate and repair the open in the sensor power [+] line (pin G1). Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 1-1 OR 1-2 Test 8 Checking for a shorted signal to ground in the harness

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1A connector pin F2 (the oil pressure signal [+] line) to a good ground.

If the voltage is greater than 0.5 volts, locate and repair the short to power in the oil pressure signal [+] line. Retest to be sure the problem has been corrected.

If the voltage is less than 0.5 volts, proceed to Test 18.

Test 12 Checking for a pin-to-pin short

Figure 26 — Continuity from Pin C to Ground

1. Turn the ignition key to the OFF position.

2. Check for continuity from harness connector pin C (the signal [+] line) to a good ground.

If there is continuity, proceed to Test 17.

If there is no continuity, proceed to Test 16.

Test 9 Checking the harness for stray voltage Figure 28 — Inspect for a Short around Pin G1

1. Disconnect the serial link jumper.

2. Visually inspect the J1A connector, on the module end, for a pin-to-pin short around pin G1.

Figure 27 — Voltage from Pin F2 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A and J1B connectors from the V-MAC II module.

Page 34

If there is a repairable short, repair the short to power in the J1A connector. Replace the oil pressure sensor. Retest to be sure the problem has been corrected.

If there is not a repairable short, replace the V-MAC II module and the oil pressure sensor.

Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 1-1 OR 1-2 Test 14

Test 16

Checking for a short to ground in the sensor power (+) line

Checking for an open in the signal line in the harness

Figure 29 — Continuity from Pin G1 to Ground

1. Turn the ignition key to the OFF position.

2. Check for continuity from J1A connector pin G1 (the sensor power [+] line) to a good ground.

Figure 30 — Jumper between Pins B and C

If there is continuity, locate and repair the short to ground in the voltage reference (+) line in the harness or connector. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 28.

Figure 31 — Continuity between Pins G1 and F2

1. Turn the ignition key to the OFF position.

2. Connect a jumper between harness connector pins B and C. 3. Disconnect the J1A connector from the V-MAC II module.

4. Check for continuity between J1A connector pins G1 (the sensor power [+] line) and F2 (the oil pressure signal [+] line).

If there is continuity, disconnect the jumper and proceed to Test 32.

If there is no continuity, locate and repair the open in the oil pressure signal [+] line in the harness or connectors. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 1-1 OR 1-2 Test 17 Checking for continuity to ground on the oil pressure signal line

3. Check for continuity between J1A connector pin F2 (the oil pressure signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, locate and repair the short in the oil pressure signal [+] line.

Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 36.

Test 28 Checking for a pin-to-pin short in the harness Figure 32 — Continuity from Pin F2 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A connector from the V-MAC II module.

3. Check for continuity from J1A connector pin F2 (the oil pressure signal [+] line) to a good ground.

If there is continuity, locate and repair the short to ground in the oil pressure signal [+] line. Retest to be sure the problem has been corrected.

Figure 34 — Continuity between Pin G1 and All Other Pins

If there is no continuity, proceed to Test 34.

1. Turn the ignition key to the OFF position.

2. Remove the jumper between pins B and C.

Test 18 Checking for a pin-to-pin short in the harness

3. Disconnect the J1B and J2 connectors from the V-MAC II module.

4. Check for continuity between J1A connector pin G1 (the sensor power [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, locate and repair the short to ground in the sensor power [+] line in the harness or connector. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 56.

Figure 33 — Continuity between Pin F2 and All Other Pins

1. Disconnect the serial link jumper.

2. Disconnect the J2 connector from the V-MAC II module.

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DIAGNOSTIC CODE 1-1 OR 1-2 Test 32

Test 34

Checking continuity from the ground (−) line to ground

Checking for a pin-to-pin short in the harness

Figure 36 — Continuity between Pin F2 and All Other Pins

1. Turn the ignition key to the OFF position.

2. Disconnect the J1B and J2 connectors from the V-MAC II module.

Figure 35 — Continuity from Pin A to Ground

1. Turn the ignition key to the OFF position.

2. Connect the J1A connector to the V-MAC II module.

3. Check for continuity from harness connector pin A (the ground [−] line) to a good ground.

3. Check for continuity between J1A connector pin F2 (the oil pressure signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, locate and repair the short in the oil pressure signal [+] line.

Retest to be sure the problem has been corrected.

If there is continuity, proceed to Test 64.

If there is no continuity, proceed to Test 68.

If there is no continuity, proceed to Test 65.

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DIAGNOSTIC CODE 1-1 OR 1-2 Test 36

Test 56

Checking for a pin-to-pin short at the V-MAC II module connector

Checking for an open or short at the V-MAC II module connector

Figure 37 — Inspect for a Short between Pin F2 and Any Other Pin

Figure 38 — Inspect for an Open or Short between Pin G1 and Any Other Pin

1. Visually inspect the module side of the J1A connector for a repairable short between pin F2 (the oil pressure signal [+] line) and any other pin.

1. Visually inspect the module side of the J1A connector for an open or short around pin G1 (the sensor power [+] line).

If there is a repairable condition, repair the short between the pins. Retest to be sure the problem has been corrected.

If there is not a repairable condition, the V-MAC II module is damaged. The sensor may also be damaged if the failure was the result of the ground line being shorted to voltage. Replace both the V-MAC II module and the oil pressure sensor. Retest to be sure the problem has been corrected.

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If there is a repairable condition, repair the short or open on the J1A connector. Retest to be sure the problem has been corrected.

If there is not a repairable condition, reconnect the V-MAC II harnesses and the oil pressure sensor connector. Turn the ignition key to the ON position. If blink code 1-1 is still active, replace the V-MAC II module. If the fault is not active, check for loose connections at the sensor and module connectors. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 1-1 OR 1-2 Test 64

Test 65

Checking for an open in the V-MAC II module

Checking for an open in the sensor ground (−) line

Figure 39 — Jumper between Pins B and C

Figure 40 — Jumper between Pins A and C

1. Connect a jumper between harness connector pins B and C. 2. Turn the ignition key to the ON position.

If the active fault changes from voltage low (code 1-1) to voltage high (code 1-2), proceed to Test 128.

If the active fault does not change, turn the ignition key to the OFF position. Check the V-MAC II module connectors for dirt which could cause a short to ground. Repair the short or replace the V-MAC II module. Retest to be sure the problem has been corrected.

Figure 41 — Continuity between Pins G2 and F2

1. Connect a jumper between harness connector pins A and C. 2. Disconnect the J1A connector from the V-MAC II module.

3. Check for continuity between J1A connector pins F2 (the oil pressure signal [+] line) and G2 (the sensor ground [−] line).

If there is continuity, proceed to Test 130.

If there is no continuity, locate and repair the open in the sensor ground (−) line. This open may be in the harness or connector. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 1-1 OR 1-2 Test 68

Test 128

Checking for a repairable short at the V-MAC II module

Checking for a fault in the sensor connector

Figure 43 — Inspect Both Sides of Sensor for an Open

1. Visually inspect both sides of the sensor connector for a repairable open in any of the pins.

Figure 42 — Inspect for a Short between Pin F2 and All Adjacent Pins

1. Visually inspect the module end of the J1A connector for a short between pin F2 (the oil pressure signal [+] line) and all adjacent pins.

If there is a repairable short, repair the short at the connector on the oil pressure signal [+] line.

Retest to be sure the problem has been corrected.

If there is not a repairable short, replace the V-MAC II module. Retest to be sure the problem has been corrected.

It is good practice to be sure the test leads in your electrical test kit are in good condition (not bent or damaged in any way).

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If there is a repairable open, repair or replace the oil pressure sensor connector. Retest to be sure the problem has been corrected.

If there is not a repairable open, continue with the next step.

2. Find the gray J 35616-2 male test lead from the J 38581 V-MAC jumper wire kit. Align the male test lead with one of the rectangular female pins in the sensor connector. Gently push the test lead into the sensor connector pin. Repeat this process for the remaining two female pins, being careful to align the lead with the rectangular pins (pin C is turned 90 degrees from pins A and B).

If any of the pins in the connector feel loose, repair or replace the connector. Retest to be sure the problem has been corrected.

If none of the pins in the connector feel loose, continue with the next step.

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DIAGNOSTIC CODE 1-1 OR 1-2 3. Find the gray J 35616-3 female test lead from the J 38581 V-MAC jumper wire kit.

Align the female test lead with one of the rectangular male pins in the oil pressure sensor. Gently push the test lead over the pin. Repeat this procedure for the remaining two male pins, being careful to align the lead with the rectangular pins (pin C is turned 90 degrees from pins A and B).

If any of the pins in the sensor feel loose, replace the sensor. Retest to be sure the problem has been corrected.

If none of the pins in the connector feel loose, proceed to Test 256.

Test 130 Checking for a repairable open at the V-MAC II module connector

1. Visually inspect both sides of the J1A connector around pin G2 (the sensor ground [−] line) for a repairable open.

If there is a repairable open, repair the J1A connector. Retest to be sure the problem has been corrected.

If there is not a repairable open, replace the J1A connector or V-MAC II module (if necessary).

Retest to be sure the problem has been corrected.

Test 256 Checking for bad contact in the sensor connector 1. Reconnect the sensor.

2. Start the engine and flex the engine harness near the sensor.

If, at any time, the fault becomes inactive, repair or replace the sensor connector. Retest to be sure the problem has been corrected.

Otherwise, replace the oil pressure sensor.

Retest to be sure the problem has been corrected.

Figure 44 — Inspect Around Pin G2 for an Open

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DIAGNOSTIC CODE 1-7 DIAGNOSTIC BLINK CODE 1-7 COOLANT LEVEL SENSOR TESTS DIAGNOSTIC CODE 1-7

Figure 45 — Diagnostic Procedure Flowchart

Test 1 Checking the coolant level When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

1. Check the coolant level in the radiator.

If the radiator is filled to the neck of the filler tube, proceed to Test 2.

Blink Code

1-7

PID

111

SID FMI

3

MID

142

Name

Engine Coolant Level

Failure

Voltage above normal or shorted high

Avoid injury when checking coolant in a hot engine. Whenever possible, wait for the engine to cool prior to checking the level.

Turn the radiator cap counterclockwise to the first stop, but do not depress. After the pressure has completely dissipated, press the cap downward and continue turning to remove.

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If the radiator is not filled to the neck of the filler tube, fill the radiator. Check for the cause of the low coolant and check to see if the fault is still active.

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DIAGNOSTIC CODE 1-7 Test 2

Test 4

Checking the voltage on the sensor

Checking the voltage on the harness

Figure 46 — Voltage between Pin A and Ground

Figure 47 — Voltage between Pin F3 and Ground

1. Turn the ignition key to the OFF position.

1. Turn the ignition key to the OFF position.

2. Disconnect the harness from the coolant level sensor.

2. Disconnect the J1A and J1B connectors from the V-MAC II module.

3. Turn the ignition key to the ON position.

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from harness connector pin A (the signal [+] line) to a good ground.

If the voltage is greater than or equal to about 5 volts, proceed to Test 4.

If the voltage is much less than 5 volts, proceed to Test 5.

4. Measure the voltage from J1A connector pin F3 (the coolant level signal [+] line) to a good ground.

If the voltage is greater than 2 volts, locate and repair the short to voltage on the coolant level signal [+] line. Retest to be sure the problem has been corrected.

If the voltage is less than 2 volts, proceed to Test 8.

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DIAGNOSTIC CODE 1-7 Test 5

Test 8

Checking for continuity in the harness

Checking for an open ground line

Figure 48 — Jumper from Pin A to Ground

Figure 50 — Jumper between Pins A and B

Figure 49 — Continuity from Pin F3 to Ground

1. Turn the ignition key to the OFF position.

Figure 51 — Continuity from Pin F3 to Ground

2. Disconnect the J1A connector from the V-MAC II module.

1. Disconnect the serial link jumper.

3. Connect a jumper from harness connector pin A to a good ground.

2. Connect a jumper between harness connector pins A and B.

4. Check for continuity from J1A connector pin F3 (the coolant level signal [+] line) to a good ground.

3. Check for continuity from J1A connector pin F3 (the coolant level signal [+] line) to a good ground.

If there is continuity, proceed to Test 10.

If there is continuity, proceed to Test 16.

If there is no continuity, there is an open in the coolant level signal [+] line. Repair the open in the harness. Retest to be sure the problem has been corrected.

If there is no continuity, the coolant level ground [−] line is open. Locate and repair the open.

Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 1-7 Test 10

Test 16

Checking for pin-to-pin continuity

Checking for pin-to-pin continuity

Figure 52 — Continuity between Pin F3 and All Other Pins

Figure 53 — Continuity between Pin F3 and All Other Pins

1. Turn the ignition key to the OFF position.

1. Disconnect the J2 connector from the V-MAC II module.

2. Remove the jumper from pin A to ground.

3. Disconnect the J2 connector from the V-MAC II module.

4. Check for continuity between J1A connector pin F3 (the coolant level signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, locate and repair the short. Retest to be sure the problem has been corrected.

2. Disconnect the jumper between pins A and B. 3. Check for continuity between J1A connector pin F3 (the coolant level signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 32.

If there is no continuity, proceed to Test 20.

Test 20 Checking for a defective V-MAC II module 1. Reconnect the sensor.

2. Reconnect the V-MAC II harness connectors.

3. Turn the ignition key to the ON position.

If code 1-7 is still active, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If code 1-7 is no longer active, the procedure has corrected the problem. Clean and inspect the connections.

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DIAGNOSTIC CODE 1-7 Test 32

Test 64

Checking for a failed sensor

Checking for a damaged connector

1. Replace the coolant level sensor.

2. Reconnect the J1A, J1B, and J2 connectors.

3. Turn the ignition key to the ON position.

If code 1-7 is active, proceed to Test 64.

If code 1-7 is no longer active, replacing the sensor has corrected the problem.

Figure 54 — Inspect for Damaged, Broken or Missing Pins

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A connector from the V-MAC II module.

3. Visually inspect for damaged, broken or missing pins on the J1A connector.

If damage is evident, repair or replace the J1A connector (if possible).

If there is no evidence of damage, reconnect the circuit and turn the ignition key to the ON position.

If the fault is still present, replace the V-MAC II module. If the fault is not present, the procedure has corrected the problem. Clean and inspect the connections.

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DIAGNOSTIC CODE 1-8 DIAGNOSTIC BLINK CODE 1-8 STARTER INPUT TESTS DIAGNOSTIC CODE 1-8

Figure 55 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

This fault becomes active if the engine is running and the input voltage to the starter relay remains high. This fault will not become active until the engine is running. If the fault is active and the engine stops, the fault will become inactive.

1-8

PID SID

237

FMI

3

MID

142

Name

Starter Input

Failure

Voltage above normal or shorted high

This fault will not become active if the starter relay becomes stuck in the engaged position unless the key is also in the start position.

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DIAGNOSTIC CODE 1-8 Test 1

Test 3

Checking the ignition position

Checking switch status

1. Turn the ignition key to the ON position.

If the starter engages, proceed to Test 2.

1. With the ignition key still in the ON position, check the switch status of the starter input (Aux 3 input) using a diagnostic tool (Pro-Link or PC).

If the starter does not engage, proceed to Test 3.

If the diagnostic tool indicates that the starter is ON, proceed to Test 6.

Test 2 Checking the diode

If the diagnostic tool indicates that the starter is OFF, proceed to Test 7.

Test 5 Some chassis do not have a connection via a diode between the starter and the accessory relay. If there is no provision in the wiring for this diode, proceed to Test 5.

1. Turn the ignition key to the OFF position.

2. Remove the diode, located on the electrical equipment panel, which connects wire J2-A3-0.8 (from the starter) to wire J1B-R3-0.8 (from the accessory relay).

3. Turn the ignition key to the ON position.

If the starter engages, proceed to Test 5.

If the starter does not engage, the diode is shorted. Replace the diode. Retest to be sure the problem has been corrected.

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Checking for a push-button start switch 1. Turn the ignition key to the OFF position.

2. Locate and disconnect the connector for the optional push-button start switch, which is attached to wire J1B-M3-0.8 (from the ignition switch).

If the vehicle uses a push-button start switch, proceed to Test 10.

If the vehicle does not use a push-button start switch, proceed to Test 11.

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DIAGNOSTIC CODE 1-8 Test 6

Test 7

Checking for a short to voltage

Confirming the fault 1. Start the engine.

If after several minutes code 1-8 does not become active, the problem may be intermittent in nature and hard to diagnose. The fault may have been caused by accidental engagement of the starter. Determine, from the customer, the conditions that existed when the code became active in order to duplicate the conditions.

If code 1-8 becomes active, proceed to Test 14.

Figure 56 — Voltage from Pin A3 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J2 connector from the V-MAC II module.

Test 10 Checking for a faulty push-button start switch

3. Turn the ignition key to the ON position.

1. Remove the push-button start switch from the harness connector.

4. Measure the voltage from J2 connector pin A3 (the starter signal [+] line) to a good ground.

2. With the button in the OFF position, check for continuity between pins A and B of the push-button start switch.

If the voltage is greater than 5 volts, there is a short to voltage on wire J2-A3-0.8. Locate and repair the short. Since the starter is not engaged, it is also possible that there is a break in the same wire before it reaches the starter relay. Once the short to voltage is repaired, check the switch status when the starter is engaged. If the switch status indicated that the starter (Aux 3) is not engaged, there is also an open in the wire.

Locate and repair the open. Retest to be sure the problem has been corrected.

If there is continuity, replace the push-button start switch. Retest to be sure the problem has been corrected.

If there is no continuity, there is a short in the harness between wire J2-A3-0.8 and 12 volts.

Locate and repair the short.

If the voltage is less than 5 volts, proceed to Test 12.

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DIAGNOSTIC CODE 1-8 Test 11 Checking for a faulty switch 1. Turn the ignition key to the ON position.

2. Disconnect the push-button start bypass connector.

3. Measure the voltage from pin B (wire 2-D-0.8), on the key switch side of the push-button start bypass connector, to a good ground.

If the diagnostic tool indicates the correct starter status, the procedures have corrected the problem. Check all connectors to ensure proper connections.

If the diagnostic tool indicates that the starter is ON when it is not, replace the V-MAC II module.

Retest to be sure the problem has been corrected.

Test 14 Checking for an intermittent short

If 12 volts are present, the key switch is shorted internally. Replace the key switch. Retest to be sure the problem has been corrected.

If 12 volts are not present, continue with the next step.

4. With the push-button start bypass connector still disconnected, measure the voltage from pin B (wire J2-A3-0.8) on the circuit side of the connector to a good ground.

If 12 volts are present, there is a short to power in the harness between wire J2-A3-0.8 and 12 volts.

Locate and repair the short. Retest to be sure the problem has been corrected.

If 12 volts are not present, the circuit is functioning properly and the problem is somewhere else in the system. Retest to be sure the problem has been corrected.

Test 12 Checking for a defective connector 1. Visually inspect the J2 connector on both the module and harness sides for bent pins, contamination or corrosion or any other cause of a short.

If there is a repairable condition, repair the connector. Retest to be sure the problem has been corrected.

If there is not a repairable condition, continue with the next step.

2. Clean the connector, reconnect the module and check the switch status with a diagnostic tool (Pro-Link or PC).

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1. With the engine running and code 1-8 still active, disconnect the J2 connector from the V-MAC II module.

If code 1-8 becomes inactive, there is an intermittent short to voltage on wire J2-A3-0.8.

Locate and repair the short. Then continue with the next step.

If code 1-8 does not become inactive, replace the V-MAC II module. Retest to be sure the problem has been corrected.

Since the starter is not engaged, it is also possible that there is also a break in this same wire before it reaches the starter relay.

2. Once the short to voltage is repaired, check the switch status when the starter is engaged using a diagnostic tool (Pro-Link or PC).

If the switch status indicates that the starter (Aux 3 input) is not engaged, there is also an open in the wire. Locate and repair the open. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 2-1 OR 2-2 DIAGNOSTIC BLINK CODE 2-1 OR 2-2 COOLANT TEMPERATURE SENSOR TESTS DIAGNOSTIC CODE 2-1 OR 2-2

Figure 57 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

2-1

2-2

PID

110

110

FMI

4

3

MID

142

142

Name

Engine Coolant Temperature

Engine Coolant Temperature

Failure

Voltage below normal or shorted low

Voltage above normal or shorted high

SID

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DIAGNOSTIC CODE 2-1 OR 2-2 Test 1 Checking sensor resistance

1. Check for continuity from either lead (pin A or pin B) of the sensor to a good ground.

If there is continuity, replace the sensor. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 4.

Test 3 Checking the signal line for voltage

Figure 58 — Resistance between Pins A and B

1. Turn the ignition key to the OFF position.

2. Disconnect the coolant temperature sensor from the harness.

3. Measure the resistance between harness connector pins A (the signal [+] line) and B (the ground [−] line) with the coolant temperature between 0 and 90°C (32 and 94°F).

If the resistance is between 200 and 9400 ohms, proceed to Test 2.

If the resistance is not between 200 and 9400 ohms, proceed to Test 3.

Test 2 Checking for a short to ground in the sensor

Figure 60 — Voltage between Pin A and Ground

1. Turn the ignition key to the ON position.

2. Measure the voltage from harness connector pin A (the signal [+] line) to a good ground.

If the voltage is greater than 6 volts, proceed to Test 6.

If the voltage is less than 6 volts, visually inspect the sensor connector for a repairable short or open. If there is a repairable condition, locate and repair the short or open on the sensor. If there is not a repairable condition, replace the sensor.

Retest to be sure the problem has been corrected.

Figure 59 — Voltage from Sensor Lead to Ground (Pin A Shown)

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DIAGNOSTIC CODE 2-1 OR 2-2 Test 4

1. Turn the ignition key to the OFF position.

Checking for proper supply voltage to the sensor

2. Disconnect the J1A, J1B and J2 connectors from the V-MAC II module.

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1A connector pin E1 (the coolant temperature [+] line) to a good ground.

If the voltage is greater than 6 volts, the signal line is shorted to voltage somewhere the harness.

Locate and repair the short, and replace the sensor. Retest to be sure the problem has been corrected.

If there is no voltage indicated, proceed to Test 12.

Figure 61 — Voltage from Pin A to Ground

1. Turn the ignition key to the ON position.

Test 8

2. Measure the voltage from harness connector pin A (the signal [+] line) to a good ground.

Checking for proper voltage on the ground terminal on the sensor side of the connector

If the voltage is between 4.5 and 5.5 volts, proceed to Test 8.

If the voltage is not within this range, proceed to Test 9.

Test 6 Checking for a short to 12 volts on the signal line

Figure 63 — Voltage from Pin B to Ground

1. Measure the voltage from harness connector pin B (the ground [+] line) to a good ground.

Figure 62 — Voltage from Pin E1 to Ground

If the voltage is greater than 0.5 volts, proceed to Test 17.

If the voltage is less than 0.5 volts, proceed to Test 16.

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DIAGNOSTIC CODE 2-1 OR 2-2 Test 9

Test 12

Checking for a short in the harness between the V-MAC II module and the sensor

Checking for a short in the V-MAC II connector

Figure 64 — Jumper between Pins E1 and E2

Figure 66 — Continuity between Pin E1 and All Other Pins

1. Disconnect the serial link jumper.

2. Check for continuity between J1A connector pin E1 (the coolant temperature [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, there is a short between pin E1 and the line which showed continuity in the harness. Locate and repair the short, and replace the sensor. Retest to be sure the problem has been corrected.

Figure 65 — Continuity between Pins A and B

If there is no continuity, proceed to Test 24.

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A engine connector from the V-MAC II module.

3. Connect a jumper between J1A connector pins E1 and E2.

4. Check for continuity between harness connector pins A (the signal [+] line) and B (the ground [−] line).

If there is continuity, proceed to Test 18.

If there is no continuity, there is an open in the signal line in the harness, on the harness side of the sensor connector or on the J1A connector.

Locate and repair the open. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 2-1 OR 2-2 Test 16

Test 17

Checking for continuity to ground on the ground line in the harness

Checking for an external short to voltage on the ground line

Figure 67 — Continuity from Pin B to Ground

Figure 68 — Voltage from Pin B to Ground

1. Turn the ignition key to the OFF position.

1. Turn the ignition key to the OFF position.

2. Check for continuity from harness connector pin B (the ground [−] line) to a good ground.

2. Disconnect the J1A, J1B and J2 connectors from the V-MAC II module.

If there is continuity, proceed to Test 32.

3. Connect the serial link jumper into the serial communication port.

If there is no continuity, proceed to Test 33.

4. Measure the voltage from harness connector pin B (the ground [−] line) to a good ground.

If the voltage is greater than 0.5 volts, there is a short in the ground line in the harness, on the sensor connector harness side, or on the J1A connector. Locate and repair the short, and replace the V-MAC II module. Retest to be sure the problem has been corrected.

If the voltage is less than 0.5 volts, proceed to Test 34.

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DIAGNOSTIC CODE 2-1 OR 2-2 Test 18

Test 24

Checking for an external voltage short to the signal line in the harness

Checking for a defective connector or V-MAC II module

Figure 69 — Voltage from Pin E1 to Ground

1. Remove the jumper between J1A connector pins E1 and E2.

2. Disconnect the J1B and J2 connectors from the V-MAC II module.

Figure 70 — Inspect for a Short between Pin A and 12-volt Supply

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1A connector pin E1 (the coolant temperature [+] line) to a good ground.

If the voltage is greater than 0.5 volts, the signal line is shorted to voltage in the harness, or on the harness side of the sensor or J1A connector.

Locate and repair the short. Retest to be sure the problem has been corrected.

If the voltage is less than 0.5 volts, proceed to Test 36.

Figure 71 — Inspect for a Short between Pin E1 and 12-volt Supply

1. Visually inspect the coolant temperature sensor harness connector for a short between pin A and a 12-volt supply, and the J1A connector for a short between pin E1 and a 12-volt supply.

If there is a repairable short, repair the short and replace the sensor. Retest to be sure the problem has been corrected.

If there is not a repairable short, replace the sensor and the J1A connector or V-MAC II module. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 2-1 OR 2-2 Test 32 Checking for an external short to voltage on the signal line in the harness

Figure 74 — Continuity between Pins A and B

1. Turn the ignition key to the OFF position.

Figure 72 — Voltage from Pin E1 to Ground

1. Disconnect the J1A, J1B and J2 connectors from the V-MAC II module.

2. Connect the serial link jumper into the serial communication port.

3. Measure the voltage from J1A connector pin E1 (the coolant temperature [+] line) to a good ground.

If the voltage is greater than 0.5 volts, the signal line is shorted in the harness, or on the harness side of the sensor connector or the J1A connector. Locate and repair the short. Retest to be sure the problem has been corrected.

2. Disconnect the J1A connector from the V-MAC II module.

3. Connect a jumper between J1A connector pins E1 and E2.

4. Check for continuity between harness connector pins A (the signal [+] line) and B (the ground [−] line).

If there is continuity, proceed to Test 66.

If there is no continuity, there is an open in the ground line in the harness or on the harness side of the connector. Locate and repair the open.

Retest to be sure the problem has been corrected.

If the voltage is less than 0.5 volts, proceed to Test 64.

Test 33 Checking for an open in the ground line in the harness

If the coolant temperature fault (code 2-1 or 2-2) is not accompanied by an air temperature fault (code 2-3 or 2-4), the open in the ground line is near the sensor, somewhere after the ground line breaks of the common ground with the air temperature sensor. If there is also an air temperature fault, the open is farther back in the harness.

Figure 73 — Jumper between Pins E1 and E2

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DIAGNOSTIC CODE 2-1 OR 2-2 Test 34

1. Disconnect the serial link jumper.

Checking for a pin-to-pin short in the harness

2. Check for continuity from J1A connector pin E1 (the coolant temperature [+] line) to a good ground.

If there is continuity, the signal line is shorted to ground in the harness or on the J1A connector.

Locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 72.

Figure 75 — Continuity between Pin E2 and All Other Pins

1. Disconnect the serial link jumper.

Test 64 Checking for a pin-to-pin short on the signal line in the harness

2. Check for continuity between J1A connector pin E2 (the coolant temperature [−] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, the ground line is shorted to voltage in the harness or in the connector. Locate and repair the short and replace the V-MAC II module. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 68.

Figure 77 — Continuity between Pin E1 and All Other Pins

1. Disconnect the serial link jumper.

Test 36 Checking for a short to ground in the signal line in the harness

2. Check for continuity between J1A connector pin E1 (the coolant temperature [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, there is a 5-volt pin-to-pin short in the signal line in the harness. Locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 128.

Figure 76 — Continuity from Pin E1 to Ground

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DIAGNOSTIC CODE 2-1 OR 2-2 Test 66

Test 68

Checking for an open in the V-MAC connector

Checking for a defective sensor connection

Figure 79 — Resistance between Pins A and B

Figure 80 — Resistance between Pins E1 and E2 Figure 78 — Inspect for an Open on Both Sides of the Connector at Pin E2

1. Visually inspect both sides of the J1A connector for an open around pin E2.

1. Remeasure the resistance across the two leads of the sensor (pins A and B) with the coolant temperature between 0 and 90°C (32 and 194°F).

If there is a repairable open, locate and repair the open. Retest to be sure the problem has been corrected.

2. Connect the coolant temperature sensor to the harness.

If there is not a repairable open, replace the V-MAC II module or J1A connector. Retest to be sure the problem has been corrected.

3. Measure the resistance between J1A connector pins E1 (the coolant temperature [+] line) and E2 (the coolant temperature [−] line).

If the resistance is within 20 ohms of the resistance across the bare sensor (step 1 above), proceed to Test 136.

If the resistance is not within 20 ohms of the resistance across the bare sensor, there is an open on the sensor connector, or (less likely) at the bulkhead connector. Locate and repair the open. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 2-1 OR 2-2 Test 72

Test 128

Checking for a pin-to-pin short in the harness

Checking for an open in the sensor connector

Figure 81 — Continuity between Pin E1 and All Other Pins

Figure 82 — Resistance between Pins A and B

1. Check for continuity between J1A connector pin E1 (the coolant temperature [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, the signal line is shorted to ground in the sensor connector or one of the V-MAC connectors. Locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 144.

Figure 83 — Resistance between Pins E1 and E2

1. Remeasure the resistance across the two leads of the sensor (pins A and B) with the coolant temperature between 0 and 90° C (32 and 194°F).

2. Reconnect the coolant temperature sensor.

3. Measure the resistance between J1A connector pins E1 (the coolant temperature [+] line) and E2 (the coolant temperature [−] line).

If the resistance is within 20 ohms of the resistance across the bare sensor (step 1 above), proceed to Test 256.

If the resistance is not within 20 ohms of the resistance across the bare sensor, there is an open in the sensor connector, or (less likely) at the bulkhead connector. Locate and repair the open. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 2-1 OR 2-2 Test 136

Test 256

Checking for a short in the V-MAC II connectors

Checking for a defective V-MAC II module or a loose connector

1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

2. Turn the ignition key to the ON position.

2. Turn the ignition key to the ON position.

If blink code 2-1 or 2-2 is still active, check the V-MAC II module and connectors for dirt, loose or broken pins, or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If blink code 2-1 or 2-2 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If blink code 2-1 or 2-2 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

If blink code 2-1 or 2-2 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

Test 144 Checking for an open or short in the V-MAC II connectors 1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

2. Turn the ignition key to the ON position.

If blink code 2-1 or 2-2 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If blink code 2-1 or 2-2 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

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DIAGNOSTIC CODE 2-3 OR 2-4 DIAGNOSTIC BLINK CODE 2-3 OR 2-4 INTAKE MANIFOLD AIR TEMPERATURE SENSOR TESTS DIAGNOSTIC CODE 2-3 OR 2-4

Figure 84 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

2-3

2-4

PID

105

105

4

3

SID FMI MID

142

142

Name

Intake Manifold Air Temperature

Intake Manifold Air Temperature

Failure

Voltage below normal or shorted low

Voltage above normal or shorted high

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 1 Checking sensor resistance

1. Check for continuity from either lead of the sensor (pin A or B) to a good ground.

If there is continuity, replace the sensor. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 4.

Test 3 Checking the signal line for voltage

Figure 85 — Resistance between Pins A and B

1. Turn the ignition key to the OFF position.

2. Disconnect the intake manifold temperature sensor from the harness.

3. Measure the resistance across the two leads of the sensor (pins A and B) with the intake manifold temperature between 0 and 90°C (32 and 194°F).

If the resistance is between 200 and 9400 ohms, proceed to Test 2.

If the resistance is not between 200 and 9400 ohms, proceed to Test 3.

Test 2 Checking for a short to ground in the sensor

Figure 87 — Voltage from Pin A to Ground

1. Turn the ignition key to the ON position.

2. Measure the voltage from harness connector pin A (the signal [+] line) to a good ground.

If the voltage is greater than 6 volts, proceed to Test 6.

If the voltage is less than 6 volts, visually inspect the sensor connector for a repairable short or open. If there is a repairable condition, locate and repair the short or open on the sensor. If there is not a repairable condition, replace the sensor.

Retest to be sure the problem has been corrected.

Figure 86 — Continuity from Pin A or B to Ground

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 4

Test 6

Checking for proper supply voltage to the sensor

Checking for a short to 12 volts on the signal line

Figure 89 — Voltage from Pin D3 to Ground

1. Turn the ignition key to the OFF position.

Figure 88 — Voltage from Pin A to Ground

1. Turn the ignition key to the ON position.

2. Measure the voltage from harness connector pin A (the signal [+] line) to a good ground.

If the voltage is between 4.5 and 5.5 volts, proceed to Test 8.

If the voltage is not within this range, proceed to Test 9.

2. Disconnect the J1A and J1B connectors from the V-MAC II module.

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1A connector pin D3 (the intake manifold temperature signal [+] line) to a good ground.

If the voltage is greater than 6 volts, the signal line is shorted to voltage somewhere in the harness. Locate and repair the short, and replace the sensor. Retest to be sure the problem has been corrected.

If there is no voltage indicated, proceed to Test 12.

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 8

Test 9

Checking for proper voltage on the ground line on the sensor side of the connector

Checking for a short in the harness between V-MAC and the sensor

Figure 91 — Jumper between Pins D3 and E2

Figure 90 — Voltage from Pin B to Ground

1. Measure the voltage from harness connector pin B (the ground [−] line) to a good ground.

If the voltage is greater than 0.5 volts, proceed to Test 17.

If the voltage is less than 0.5 volts, proceed to Test 16.

Figure 92 — Continuity between Pins A and B

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A connector from the V-MAC II module.

3. Connect a jumper between J1A connector pins D3 and E2.

4. Check for continuity between harness connector pins A (the signal [+] line) and B (the ground [−] line), on the sensor side of the connector.

If there is continuity, proceed to Test 18.

If there is no continuity, there is an open in the signal line in the harness, on the harness side of the connector, or in the J1A connector. Locate and repair the open. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 12

Test 16

Checking for a short in the V-MAC II connector

Checking for continuity to ground on the ground line in the harness

Figure 93 — Continuity between Pin D3 and All Other Pins

1. Disconnect the serial link jumper.

2. Disconnect the J2 connector from the V-MAC II module.

3. Check for continuity between J1A connector pin D3 (the intake manifold temperature signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, there is a short between pin D3 and the line which showed continuity in the harness. Locate and repair the short, and replace the sensor. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 24.

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Figure 94 — Continuity from Pin B to Ground

1. Turn the ignition key to the OFF position.

2. Check for continuity from harness connector pin B (the ground [−] line) to a good ground.

If there is continuity, proceed to Test 32.

If there is no continuity, proceed to Test 33.

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 17

Test 18

Checking for an external short to voltage on the ground line

Checking for an external voltage short to the signal line in the harness

Figure 96 — Voltage from Pin D3 to Ground

1. Remove the jumper between J1A connector pins D3 and E2.

Figure 95 — Voltage from Pin B to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A and J1B connectors from the V-MAC II module.

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from harness connector pin B (the ground [−] line) to a good ground.

If the voltage is greater than 0.5 volts, there is a short in the ground line E2 in the harness, on the sensor connector harness side, or on the J1A connector. Locate and repair the short, and replace the V-MAC II module. Retest to be sure the problem has been corrected.

2. Disconnect the J1B and J2 connectors from the V-MAC II module.

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1A connector pin D3 (the intake manifold temperature signal [+] line) to a good ground.

If the voltage is greater than 0.5 volts, the signal line is shorted to voltage in the harness, or on the harness side of the sensor or J1A connector.

Locate and repair the short. Retest to be sure the problem has been corrected.

If the voltage is less than 0.5 volts, proceed to Test 36.

If the voltage is less than 0.5 volts, proceed to Test 34.

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 24

Test 32

Checking for a defective connector or V-MAC II module

Checking for an external short to voltage on the signal line in the harness

Figure 97 — Inspect for a Short between Pin D3 and a 12-volt Supply

Figure 99 — Voltage from Pin D3 to Ground

1. Disconnect the J1A, J1B and J2 connectors from the V-MAC II module.

2. Connect the serial link jumper into the serial communication port.

3. Measure the voltage from J1A connector pin D3 (the intake manifold temperature signal [+] line) to a good ground.

If the voltage is greater than 0.5 volts, the signal line is shorted in the harness, or on the harness side of the sensor connector or the J1A connector. Locate and repair the short. Retest to be sure the problem has been corrected.

Figure 98 — Inspect for a Short between Pin A and a 12-volt Supply

1. Visually inspect both the intake manifold temperature harness connector for a short between pin A and a 12-volt supply, and the J1A connector for a short between pin D3 and a 12-volt supply.

If there is a repairable short, repair the short and replace the sensor. Retest to be sure the problem has been corrected.

If there is not a repairable fault, replace the sensor and the J1A connector or V-MAC II module. Retest to be sure the problem has been corrected.

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If the voltage is less than 0.5 volts, proceed to Test 64.

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 33 Checking for an open in the ground line in the harness

If the air temperature fault (code 2-3 or 2-4) is not accompanied by a coolant temperature fault (code 2-1 or 2-2), the open in the ground line is near the sensor, somewhere after the ground line breaks off of the common ground with the coolant temperature sensor. If there is also a coolant temperature fault, the open is farther back in the harness.

Test 34 Figure 100 — Jumper between Pins D3 and E2

Figure 101 — Continuity between Pins A and B

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A connector from the V-MAC II module.

3. Connect a jumper between J1A connector pins D3 and E2.

4. Check for continuity between harness connector pins A (the signal [+] line) and B (the ground [−] line).

If there is continuity, proceed to Test 66.

If there is no continuity, there is an open in the ground line E2 in the harness or on the harness side of the sensor connector. Locate and repair the open. Retest to be sure the problem has been corrected.

Checking for a pin-to-pin short in the harness

Figure 102 — Continuity between Pin E2 and All Other Pins

1. Disconnect the serial link jumper.

2. Disconnect the J2 connector from the V-MAC II module.

3. Check for continuity between J1A connector pin E2 (the coolant temperature [−] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, the ground line (pin E2) is shorted to voltage in the harness or in the connector. Locate and repair the short and replace the V-MAC II module. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 68.

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 36 Checking for a short to the ground in the signal line in the harness

If there is continuity with another pin, there is a 5-volt pin-to-pin short in the signal line in the harness. Locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 128.

Test 66 Checking for an open in the V-MAC II connector

Figure 103 — Continuity from Pin D3 to Ground

1. Disconnect the serial link jumper.

2. Check for continuity from J1A connector pin D3 (the intake manifold temperature signal [+] line) to a good ground.

If there is continuity, the signal line is shorted to ground in the harness or on the J1A connector.

Locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 72.

Test 64 Checking for a pin-to-pin short to 5 volts on the signal line in the harness

Figure 105 — Inspect for an Open on Both Sides of the Connector at Pin E2

1. Visually inspect both sides of the J1A connector for an open around pin E2.

Figure 104 — Continuity between Pin D3 and All Other Pins

1. Disconnect the serial link jumper.

2. Check for continuity between J1A connector pin D3 (the intake manifold temperature signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

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If there is a repairable open, locate and repair the open. Retest to be sure the problem has been corrected.

If there is not a repairable open, replace the V-MAC II module or J1A connector. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 68

Test 72

Checking for a bad sensor connection

Checking for a pin-to-pin short in the harness

Figure 106 — Resistance between Pins A and B

Figure 108 — Continuity between Pin D3 and All Other Pins

1. Check for continuity between J1A connector pin D3 (the intake manifold temperature signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, the signal line is shorted to ground in the sensor connector or one of the V-MAC II connectors. Locate and repair the short. Retest to be sure the problem has been corrected.

Figure 107 — Resistance between Pins D3 and E2

If there is no continuity, proceed to Test 144.

1. Remeasure the resistance across the two leads of the sensor (pins A and B on the sensor) with the intake manifold temperature between 0 and 90°C (32 and 194°F).

2. Connect the intake manifold temperature sensor to the harness.

3. Measure the resistance between J1A connector pins D3 (the intake manifold temperature signal [+] line) and E2 (the coolant temperature [−] line).

If the resistance is within 20 ohms of the resistance across the bare sensor (step 1 above), proceed to Test 136.

If the resistance is not within 20 ohms of the resistance across the bare sensor, there is an open in the sensor connector, or (less likely) at the bulkhead connector. Locate and repair the open. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 128

Test 136

Checking for an open in the sensor connector

Checking for a short in the V-MAC II connector 1. With the ignition key in the OFF position reconnect the V-MAC II connectors.

2. Turn the ignition key to the ON position.

If blink code 2-3 or 2-4 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

Figure 109 — Resistance between Pins A and B

If blink code 2-3 or 2-4 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

Test 144 Checking for an open or short in the V-MAC II connector 1. With the ignition key in the OFF position reconnect the V-MAC II connectors.

2. Turn the ignition key to the ON position.

Figure 110 — Resistance between Pins D3 and E2

1. Remeasure the resistance across the two leads of the sensor (terminals A and B on the sensor) with the intake manifold temperature between 0 and 90°C (32 and 194°F).

2. Reconnect the intake manifold temperature sensor.

3. Measure the resistance between J1A connector pins D3 (the intake manifold temperature signal [+] line) and E2 (the coolant temperature [−] line).

If the resistance is within 20 ohms of the resistance across the bare sensor (step 1 above), proceed to Test 256.

If the resistance is not within 20 ohms of the resistance across the bare sensor, there is an open in the sensor connector, or (less likely) at the bulkhead connector. Locate and repair the open. Retest to be sure the problem has been corrected.

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If blink code 2-3 or 2-4 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If blink code 2-3 or 2-4 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

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DIAGNOSTIC CODE 2-3 OR 2-4 Test 256 Checking for a defective V-MAC II module or a loose connector 1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

2. Turn the ignition key to the ON position.

If blink code 2-3 or 2-4 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If blink code 2-3 or 2-4 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

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DIAGNOSTIC CODE 3-2 DIAGNOSTIC BLINK CODE 3-2 RPM/TDC (ENGINE POSITION) SENSOR TESTS DIAGNOSTIC CODE 3-2

Figure 111 — Diagnostic Procedure Flowchart

Test 1 Checking for an open or short in the sensor When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

3-2

PID

190

SID FMI

2

MID

142

Name

RPM/TDC (Engine Position)

Failure

Data erratic, intermittent or incorrect

The engine must be running to see an active fault on the RPM/TDC circuit.

Figure 112 — Resistance between Pins A and B

1. Turn the ignition key to the OFF position and disconnect the RPM/TDC sensor from the harness.

2. Measure the resistance between harness connector pins A (the signal [+] line) and B (the ground [−] line).

If the resistance is between 200 and 300 ohms, proceed to Test 2.

The RPM/TDC sensor signal [+] line (harness connector pin A) is connected to the RPM/TDC MINUS [−] line (J1A connector pin H2) in order to invert the signal.

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If the resistance is not between 200 and 300 ohms, repair the connector or replace the sensor.

Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 3-2 Test 2

Test 4

Checking for a short to ground in the sensor

Checking for proper RPM sensor adjustment 1. Check that the sensor is properly adjusted in the flywheel housing. For proper adjustment, turn the sensor in by hand until it bottoms.

Then back it out exactly 1 turn. Torque the jam nut to 15 lb-ft (20 N•m).

If the sensor is adjusted properly, proceed to Test 8.

Figure 113 — Continuity from Pin A to Ground

If the sensor is not adjusted properly, readjust the sensor. Retest to be sure the problem has been corrected.

Test 8 Checking for a short to voltage on the RPM PLUS line

Figure 114 — Continuity from Pin B to Ground

1. Check for continuity from harness connector pin A (the signal [+] line) to a good ground.

2. Check for continuity from harness connector pin B (the ground [−] line) to a good ground.

If there is continuity, replace the sensor. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 4.

Figure 115 — Voltage from Pin H1 to Ground

1. Disconnect the J1A and J1B connectors from the V-MAC II module.

2. Connect the serial link jumper into the serial communication port.

3. Measure the voltage from J1A connector pin H1 (the RPM/TDC PLUS [+] line) to a good ground.

If the voltage is greater than 0.5 volts, the line is shorted to another line in the harness. Locate and repair the short. Retest to be sure the problem has been corrected.

If the voltage is less than 0.5 volts, proceed to Test 16.

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DIAGNOSTIC CODE 3-2 Test 16 Checking for a short to voltage on the RPM MINUS line

Figure 118 — Continuity between Pin H2 and All Other Pins

1. Disconnect the serial link jumper.

Figure 116 — Voltage from Pin H2 to Ground

1. Measure the voltage from J1A connector pin H2 (the RPM/TDC MINUS [−] line) to a good ground.

If the voltage is greater than 0.5 volts, the line is shorted to another line in the harness. Locate and repair the short and replace the V-MAC II module.

Retest to be sure the problem has been corrected.

If the voltage is less than 0.5 volts, proceed to Test 32.

Test 32

2. Disconnect the J2 connector from the V-MAC II module.

3. Check for continuity between J1A connector pin H1 (the RPM/TDC PLUS [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

4. Check for continuity between J1A connector pin H2 (the RPM/TDC MINUS [−] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, repair the short in the harness between the pins which showed continuity. Retest to be sure the problem has been corrected.

Checking for a pin-to-pin short in the harness

If there is no continuity, proceed to Test 64.

If there is continuity with J1B connector pins P1 and P2 (ground pins), there may also be continuity with other pins. Repair the short to pins P1 and P2 first. Then retest to be sure the problem has been corrected.

Figure 117 — Continuity between Pin H1 and All Other Pins

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DIAGNOSTIC CODE 3-2 Test 64

Test 128

Checking for an open in the harness

Checking for an open on the sensor side of the connector

Figure 119 — Jumper between Pins H1 and H2 Figure 121 — Resistance between Pins H1 and H2

1. Remove the jumper between J1A connector pins H2 and H1.

2. Reconnect the RPM sensor.

3. Measure the resistance between pins J1A connector pins H1 (the RPM/TDC PLUS [+] line) and H2 (the RPM/TDC MINUS [−] line).

Figure 120 — Continuity between Pins A and B

1. Connect a jumper between J1A connector pins H2 and H1.

2. Check for continuity between harness connector pins A (the signal [+] line) and B (the ground [−] line) on the sensor side of the connector.

If the resistance is between 100 and 500 ohms, proceed to Test 256.

If the resistance is not between 100 and 500 ohms, the RPM PLUS [+] or MINUS [−] lines are open or faulty at the connector. Repair the connector if possible, otherwise, replace the sensor. Retest to be sure the problem has been corrected.

If there is continuity, proceed to Test 128.

If there is no continuity, proceed to Test 129.

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DIAGNOSTIC CODE 3-2 Test 129

Test 256

Checking for an open in the RPM line on the module end of the harness

Checking for a defective module or loose connector 1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

2. Start the engine.

If blink code 3-2 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If blink code 3-2 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

Figure 122 — Jumper between Pins H1 and P2

Figure 123 — Continuity from Pin B to Ground

1. Connect a jumper between J1A connector pin H1 and J1B connector pin P2.

2. Check for continuity from the harness connector pin B, on the sensor end of the connector, to a good ground.

If there is continuity, repair the open in the RPM line (pin H2).

If there is no continuity, select another chassis ground. If there is still no continuity, repair the RPM line (pin H1). Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 3-4 DIAGNOSTIC BLINK CODE 3-4 TIMING EVENT MARKER (TEM) TESTS DIAGNOSTIC CODE 3-4

Figure 124 — Diagnostic Procedure Flowchart

Test 1 Checking for an open or short in the sensor When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

3-4

PID SID

1

FMI

2

MID

142

Name

Timing (TEM) Sensor

Failure

Data erratic, intermittent or incorrect

Figure 125 — Resistance between Pins A and B

1. Turn ignition key to the OFF position and disconnect the TEM sensor from the harness.

The engine must be running to see an active fault on the TEM circuit.

2. Measure the resistance between pins A and B on the sensor.

If the resistance is between 100 and 500 ohms, proceed to Test 2.

If the resistance is not between 100 and 500 ohms, repair the connector or replace the sensor.

Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 3-4 Test 2 Checking for a short to ground in the sensor

1. Disconnect the J1A and J1B connectors from the V-MAC II module.

2. Connect the serial link jumper into the serial communication port.

3. Measure the voltage from J1A connector pin J1 (the TEM PLUS [+] line) to a good ground.

4. Measure the voltage from J1A connector pin J2 (the TEM MINUS [−] line) to a good ground.

Figure 126 — Continuity from Pin A to Ground

1. Check for continuity from harness connector pin A (the signal [+] line) to a good ground.

If there is continuity, replace the sensor. Retest to be sure the problem has been corrected.

If the voltage on either line is greater than 0.5 volts, the line is shorted to another line in the harness. Locate and repair the short. Retest to be sure the problem has been corrected.

If the voltage on both lines is less than 0.5 volts, proceed to Test 8.

If there is no continuity, proceed to Test 4.

Test 4 Checking for a short to voltage in the harness

To install the TEM sensor, coat the sensor threads with Silastic. Then turn the sensor body into the pump until it bottoms out. Tighten the jam nut to 22.5 lb-ft (30.5 N•m) of torque.

Test 8 Checking for proper TEM sensor adjustment 1. Check that the sensor is properly seated in the injection pump.

If it is properly seated, proceed to Test 16.

Figure 127 — Voltage from Pin J1 to Ground

Figure 128 — Voltage from Pin J2 to Ground

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If it is not properly seated, follow the instructions in the above note. Then retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 3-4 Test 16 Checking for a pin-to-pin short in the harness If there is continuity with J1B connector pins P1 and P2 (ground pins), there may also be continuity with other pins. Repair the short to pins P1 and P2 first. Then retest to be sure the problem has been corrected.

Test 32 Checking for an open in the harness Figure 129 — Continuity between Pin J1 and All Other Pins

Figure 131 — Jumper between Pins J1 and J2

Figure 130 — Continuity between Pin J2 and All Other Pins

1. Disconnect the serial link jumper.

2. Disconnect the J2 connector from the V-MAC II module.

3. Check for continuity between pin J1 (the TEM PLUS [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

4. Check for continuity between pin J2 (the TEM MINUS [−] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

Figure 132 — Continuity between Pins A and B

1. Connect a jumper between J1A connector pins J2 and J1.

2. Check for continuity between harness connector pin A (the signal [+] line) and harness connector pin B (the ground [−] line), on the sensor side of the connector.

If there is continuity with another pin, repair the short in the harness between the pins which showed continuity. Retest to be sure the problem has been corrected.

If there is continuity, proceed to Test 64.

If there is no continuity, proceed to Test 32.

If there is no continuity, proceed to Test 65.

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DIAGNOSTIC CODE 3-4 Test 64

Test 65

Checking for an open on the sensor side of the connector

Checking for an open in the TEM PLUS (+) line on the module end of the harness

Figure 133 — Resistance between Pins J1 and J2

1. Remove the jumper between J1A connector pins J2 and J1.

2. Reconnect the TEM sensor.

3. Measure the resistance between J1A connector pins J1 (the TEM PLUS [+] line) and J2 (the TEM MINUS [−] line).

Figure 134 — Jumper between Pins J1 and P2

If the resistance is between 100 and 500 ohms, proceed to Test 128.

If the resistance is not between 100 and 500 ohms, the TEM PLUS [+] or MINUS [−] lines are open or faulty at the connector. Repair the connector if possible. Otherwise, replace the sensor. Retest to be sure the problem has been corrected.

Figure 135 — Continuity from Pin A to Ground

1. Connect a jumper between J1A connector pin J1 and J1B connector pin P2.

2. Check for continuity from harness connector pin A (the signal [+] line), on the sensor side of the connector, to a good ground.

If there is continuity, repair the open in the TEM MINUS [−]line (pin J2).

If there is no continuity, select another chassis ground. If there is still no continuity, repair the TEM PLUS [+] line (pin J1). Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 3-4 Test 128 Checking for a defective module or loose connector 1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

2. Start the engine.

If blink code 3-4 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If blink code 3-4 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

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DIAGNOSTIC CODE 3-5 (BASIC) DIAGNOSTIC BLINK CODE 3-5, BASIC TIMING ACTUATOR TESTS, BASIC MECHANICAL SECTION DIAGNOSTIC CODE 3-5 (BASIC)

These diagnostic procedures are broken down into three sections: Basic Mechanical, Electrical and Advanced Mechanical. Begin with the Basic Mechanical Section.

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Figure 136 — Diagnostic Procedure Flowchart Blink Code

3-5

PID SID

2

FMI

7

MID

142

Name

Timing Actuator

Failure

Mechanical system not responding

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This fault is only active above a specific engine speed and load. It may be inactive by the time the truck reaches the service shop.

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DIAGNOSTIC CODE 3-5 (BASIC) Test 1

Test 2

Checking timing control

Checking for oil pressure from the deenergized timing control valve to the ECONOVANCE

1. Connect a diagnostic tool (Pro-Link 9000 or PC) and select the monitoring mode to display engine timing status.

2. Run the engine at low idle for at least 30 seconds and record the timing status.

3. Run the engine at high idle and record the timing status.

If the timing status at both low and high idle is correct (the diagnostic tool will indicate that timing is OK), the timing is working properly under these conditions. If the complaint indicates that the timing fault was active recently, it may be necessary to recreate the situation in which the timing fault occurred for this diagnostic procedure to be effective.

If the timing status is too advanced (the diagnostic tool will display “++”) or too retarded (the tool will display “--”), proceed to Test 2.

Figure 137 — Oil Pressure Check (Timing Control Valve)

1. Turn the ignition key to the OFF position.

2. Disconnect the timing control valve at the wiring harness.

3. Remove the cap from the diagnostic port located on top of the timing control valve.

4. Connect a pressure gauge to the diagnostic port.

5. Start the engine and record the low idle oil pressure displayed on the gauge.

If the oil pressure on the gauge is 0, proceed to Test 4.

If the pressure on the gauge is not 0, proceed to Test 5.

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DIAGNOSTIC CODE 3-5 (BASIC) Test 4

Test 8

Checking dynamic full retard timing

Checking for supply oil from the cylinder block to the ECONOVANCE

1. Connect a diagnostic tool (Pro-Link 9000 or PC). Select the monitoring mode to display engine timing.

2. Run the engine at 800 RPM for at least 30 seconds and record the timing.

If the timing on the diagnostic tool is the same as the static timing on the emissions plate (within 1 degree), proceed to Test 8.

If the timing is different from the static timing, check the RPM/TDC and TEM sensors for good connections and proper adjustment.

If, after checking the sensors, the timing on the diagnostic tool is more advanced than the static timing by more than 2 degrees, proceed to Test 9.

If, after checking the sensors, the timing on the diagnostic tool is more retarded than the static timing by more than 2 degrees, proceed to Test 9.

Test 5 Checking the timing valve retainer plate 1. Visually inspect the timing control valve for signs of oil leakage between the round valve body and the housing or from the wiring. If there is a leak, replace the entire control valve assembly.

2. If there is no oil leak, grasp the round valve body and attempt to turn it, applying light force.

If the valve body can be turned with light force, clean the front portion of the control valve and retainer plate and remove the plate. Examine the contact area of the plate and valve for signs of wear (DO NOT REMOVE THE VALVE FROM THE ASSEMBLY). If the valve is worn around the entire circumference, replace the complete timing control valve assembly. If only a portion of the valve circumference is worn, rotate the valve body so that the worn portion will not be touching a new retention plate. Install a new retention plate, using LoctiteÂŽ 242 on the plate bolts.

If there is no oil leakage and the valve body cannot be turned with light force, proceed to Test 10.

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1. Turn the ignition key to the OFF position.

2. Remove the oil supply line running from the cylinder block to the ECONOVANCE housing oil fitting.

3. Install a tee fitting at the ECONOVANCE housing.

4. Attach a pressure gauge to one side of the tee.

5. Attach an Aeroquip line from the other side of the tee to the ECONOVANCE oil supply fitting.

6. Start the engine and check the low idle oil pressure displayed on the gauge.

If the oil pressure is greater than 5 psi, proceed to the Electrical Diagnostic Test Section.

If the oil pressure is 5 psi or less, STOP THE ENGINE IMMEDIATELY! Refer to the appropriate Engine Service Manual.

Test 9 Static timing check 1. Turn the ignition key to the OFF position.

2. Check the engine static timing.

If the static timing agrees within +/s 0.5 degrees with the number stamped on the engine’s emissions plate, proceed to Test 18.

If the static timing does not agree within +/s 0.5 degrees, proceed to Test 19.

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DIAGNOSTIC CODE 3-5 (BASIC) Test 10

Test 18

Checking the control valve gasket

Checking for a defective V-MAC II module 1. Replace the V-MAC II module with a new module, or with a module from another truck.

DO NOT REPROGRAM THE MODULE AT THIS TIME. 2. Run the engine at 800 rpm for at least 30 seconds and record the timing.

If the timing on the diagnostic tool is the same as the static timing (within 1 degree), the old V-MAC II module was defective. Install a new V-MAC II module.

If the timing on the diagnostic tool disagrees with the static timing by more than 1 degree, reinstall the original V-MAC II module. A potential flywheel problem may exist. Call Service Engineering.

Figure 138 — Checking Control Valve Gasket

1. Remove the timing control valve and inspect the valve gasket.

Test 19 Checking static timing against the emissions plate

If the gasket is installed properly, proceed to Test 20.

If the static timing is more advanced than the number stamped on the emissions plate by more than 1 degree, proceed to Test 38.

If the gasket is not installed properly, correctly install a new gasket. Reinstall the timing control valve. Retest to be sure the problem has been corrected.

If the static timing is more retarded than the number by more than 1 degree, proceed to Test 39.

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DIAGNOSTIC CODE 3-5 (BASIC) Test 20 Checking for bad ECONOVANCE seals

Figure 140 — ECONOVANCE Seals

Test 38 Figure 139 — ECONOVANCE (Removing Snap Ring)

1. Replace the timing control valve.

2. With the new timing control valve disconnected and with a pressure gauge connected to the diagnostic port, start the engine. Record the low idle oil pressure displayed on the gauge.

If the oil pressure on the gauge is 0, the old control valve was defective and the procedure has corrected the problem.

If the pressure on the gauge is not 0, the old control valve was not defective and should be reinstalled. Replace the seals in the ECONOVANCE unit. Retest to be sure the problem has been corrected. Refer to the E7 Engine Service Manual for ECONOVANCE repair.

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Checking effects of advanced static timing on low idle timing 1. If the low idle timing status was correct in Test 1 (the diagnostic tool indicated that timing was OK), or was too retarded (the diagnostic tool displayed “--”), proceed to the Electrical Diagnostic Test Section.

2. If the low idle timing status in Test 1 was too advanced (the diagnostic tool displayed “++”), reset the static timing. Retest to be sure the problem has been corrected.

3. Make a note that the static timing has been reset. Then proceed to the Electrical Diagnostic Test Section.

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DIAGNOSTIC CODE 3-5 (BASIC) Test 39 Checking effects of retarded static timing on high idle timing 1. If the high idle timing status was correct in Test 1 (the diagnostic tool indicated that timing was OK), or was too advanced (the diagnostic tool displayed “++”), proceed to the Electrical Diagnostic Test Section.

2. If the high idle timing status in Test 1 was too retarded (the diagnostic tool displayed “--”), reset the static timing. Retest to be sure the problem has been corrected.

3. Make a note that the static timing has been reset. Then proceed to the Electrical Diagnostic Test Section.

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DIAGNOSTIC CODE 3-5 (ELECTRICAL) DIAGNOSTIC BLINK CODE 3-5, ELECTRICAL TIMING ACTUATOR TESTS, ELECTRICAL SECTION DIAGNOSTIC CODE 3-5 (ELECTRICAL)

These diagnostic procedures are broken down into three sections: Basic Mechanical, Electrical and Advanced Mechanical. Begin with the Basic Mechanical Section.

Figure 141 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

3-5

PID SID

2

FMI

7

MID

142

Name

Timing Actuator

Failure

Mechanical system not responding

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This fault is only active above a specific engine speed and load. It may be inactive by the time the truck reaches the service shop.

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DIAGNOSTIC CODE 3-5 (ELECTRICAL) Test 1

Test 2

Checking for an open or short in the solenoid

Checking for a short to ground in the solenoid

Figure 142 — Resistance between Pins A and B

Figure 143 — Continuity from Pin A or B to Ground (Pin A shown)

1. Turn the ignition key to the OFF position.

2. Disconnect the timing solenoid from the harness.

3. Measure the resistance across the leads of the solenoid.

1. Check for continuity from either solenoid lead (pin A or B) to a good ground.

If there is continuity, replace the solenoid. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 4.

If the resistance is between 1 and 3 ohms, proceed to Test 2.

If the resistance is not between 1 and 3 ohms, repair the connector or replace the solenoid.

Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 3-5 (ELECTRICAL) Test 4 Checking for a short to voltage in the harness

1. Disconnect the J1A and J1B connectors from the V-MAC II module.

2. Connect the serial link jumper into the serial communication port.

3. Measure the voltage from J1A connector pin A1 (the timing solenoid PLUS [+] line) to a good ground.

4. Measure the voltage from J1A connector pin A3 (the solenoid MINUS [−] line) to a good ground.

Figure 144 — Voltage from Pin A1 to Ground

If the voltage on either line is greater than 0.5 volts, that line is shorted to another line in the harness. Locate and repair the short. Retest to be sure the problem has been corrected.

If the voltage on both lines is less than 0.5 volts, proceed to Test 8.

Figure 145 — Voltage from Pin A3 to Ground

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DIAGNOSTIC CODE 3-5 (ELECTRICAL) Test 8 Checking for a pin-to-pin short in the harness If there is continuity with J1B connector pins P1 and P2 (ground pins), there may also be continuity with other pins. Repair the short to pins P1 and P2 first. Then retest to be sure the problem has been corrected.

Test 16 Checking for an open in the harness Figure 146 — Continuity between Pin A1 and All Other Pins

Figure 148 — Jumper between Pins A1 and A3 Figure 147 — Continuity between Pin A3 and All Other Pins

1. Disconnect the serial link jumper.

2. Disconnect the J2 connector from the V-MAC II module.

3. Check for continuity between J1A connector pin A1 (the timing solenoid PLUS [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

Figure 149 — Continuity between Pins A and B

4. Check for continuity between J1A connector pin A3 (the solenoid MINUS [−] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

1. Connect a jumper between J1A connector pins A3 and A1.

If there is continuity with another pin, repair the short in the harness between the pins which showed continuity. Retest to be sure the problem has been corrected.

2. Check for continuity between harness connector pins A (the signal [+] line) and B (the ground [−] line), on the solenoid end of the harness.

If there is no continuity, proceed to Test 16.

If there is continuity, proceed to Test 32.

If there is no continuity, proceed to Test 33.

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DIAGNOSTIC CODE 3-5 (ELECTRICAL) Test 32

Test 33

Checking for an open on the solenoid end of the harness

Checking for an open in the timing solenoid PLUS (+) line on the module end of the harness

Figure 150 — Resistance between Pins A1 and A3

1. Remove the jumper between J1A connector pins A3 and A1.

2. Reconnect the timing solenoid to the harness.

3. Measure the resistance between J1A connector pins A1 (the timing solenoid PLUS [+] line) and A3 (the timing solenoid MINUS [−] line).

Figure 151 — Jumper between Pins A1 and P2

If the resistance is between 1 and 3 ohms, proceed to Test 64.

If the resistance is not between 1 and 3 ohms, the timing solenoid PLUS [+] or MINUS [−] lines are open or faulty at the connector. Repair the connector if possible. Otherwise, replace the solenoid. Retest to be sure the problem has been corrected.

Figure 152 — Continuity from Pin A to Ground

1. Connect a jumper between J1A connector pin A1 and J1B connector pin P2.

2. Check for continuity from harness connector pin A (the signal [+] line), on the sensor side of the connector, to a good ground.

If there is continuity, repair the open in the timing solenoid MINUS [−] line (pin A3). Retest to be sure the problem has been corrected.

If there is no continuity, select another chassis ground. If there is still no continuity, repair the timing solenoid PLUS [+] line (pin A1). Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 3-5 (ELECTRICAL) Test 64 Checking for a defective V-MAC II module or loose connector 1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

2. Start the engine.

3. Monitor the timing status with the diagnostic tool (Pro-Link or PC).

If the diagnostic tool indicates that the timing is tracking properly, the procedure has corrected the problem. Check all connectors to ensure proper connections.

If the diagnostic tool indicates that the timing is not tracking properly, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no problems are found, proceed to the Advanced Mechanical Test Section.

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DIAGNOSTIC CODE 3-5 (ADVANCED) DIAGNOSTIC BLINK CODE 3-5, ADVANCED TIMING ACTUATOR TESTS, ADVANCED MECHANICAL SECTION DIAGNOSTIC CODE 3-5 (ADVANCED)

These diagnostic procedures are broken down into three sections: Basic Mechanical, Electrical and Advanced Mechanical. Begin with the Basic Mechanical Section.

Figure 153 — Diagnostic Procedure Flowchart

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DIAGNOSTIC CODE 3-5 (ADVANCED) Test 2 Checking dynamic timing When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

1. Turn the ignition key to the OFF position.

2. Connect the V-MAC II module connectors.

Blink Code

3-5

PID SID

2

FMI

7

MID

142

Name

Timing Actuator

Failure

Mechanical system not responding

This fault is only active above a specific engine speed and load. It may be inactive by the time the truck reaches the service shop.

Test 1 Checking timing at low idle Follow the instructions in Tests 2 through 72, running the engine at low idle. Proceed to Test 2.

3. Connect a pressure gauge to the diagnostic port.

4. Disconnect the timing valve connector from the wiring harness.

5. Connect a jumper between the two connector halves, using one set of terminals.

For example, connect the A terminals (jumper from terminal A on the harness side to terminal A on the sensor side). On the other terminals, use two jumpers to connect the circuit through a digital multimeter set to measure current (AMPS) on the 10A scale.

6. Start the engine.

7. Record the low or high idle timing, the diagnostic port pressure, and the timing valve current. Reconnect the timing valve to the harness when completed.

If the timing status shows the timing is too advanced (diagnostic tool displays “++”), proceed to Test 5.

Otherwise, proceed to Test 4.

Test 4 Checking for retarded timing

If the timing status shows the timing is too retarded (diagnostic tool displays “--”), proceed to Test 9.

Otherwise, proceed to Test 8.

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DIAGNOSTIC CODE 3-5 (ADVANCED) Test 5

Test 9

Timing is too advanced. Checking diagnostic port pressure

Timing is too retarded. Checking diagnostic port pressure

If the pressure in the diagnostic port is much less than the gallery pressure, proceed to Test 18.

If the pressure in the diagnostic port is about equal to the gallery pressure, the ECONOVANCE is stuck. Repair or replace the ECONOVANCE. Retest to be sure the problem has been corrected.

Test 10 Checking current to the timing control valve

If the current to the timing control valve is greater than 0.9 amps, proceed to Test 20.

If the current to the timing control valve is less than 0.9 amps, proceed to Test 21.

Figure 154 — Checking Timing Control Valve Port Pressure

If the pressure in the diagnostic port is greater than 0 psi (there is some pressure), proceed to Test 10.

If the pressure in the diagnostic port is 0 psi, proceed to Test 11.

Test 8 Checking timing at high idle

If you just ran Test 4 at low idle, repeat Tests 2 through 72, running the engine at high idle.

Proceed to Test 2.

If you just ran Test 4 at high idle, proceed to Test 16.

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Test 11 Checking the RPM/TDC sensor 1. Disconnect the timing valve connector from the wiring harness.

2. Record the timings at low idle and high idle.

If the high idle timing is greater than the low idle timing, replace the RPM/TDC sensor. Retest to be sure the problem has been corrected.

If the high idle timing is less than or equal to the low idle timing, proceed to Test 23.

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DIAGNOSTIC CODE 3-5 (ADVANCED) Test 16

Test 20

Determining severity and correcting the problem

Checking for wrong target, bad data file or V-MAC II module

1. Check the inactive fault table with a diagnostic tool (Pro-Link or PC).

If there are only a couple occurrences of the timing actuator fault (code 3-5) and the driver reported that the electronic fault light only came on occasionally for a brief time, there was probably a piece of debris in the timing actuator that has been flushed out. Remove the timing control valve and clean the oil supply and secondary filters. Reinstall the timing control valve, using a new gasket. Retest to be sure the problem has been corrected.

If there are numerous counts of the timing actuator fault (code 3-5) or the driver reported that the electronic fault lamp remains ON constantly, the ECONOVANCE is sticking at advanced timings. Repair or replace the ECONOVANCE. Retest to be sure the problem has been corrected.

Test 18 Checking current to the timing control valve

1. Use the diagnostic tool (Pro-Link or PC) to display the engine model, data file part number and static timing.

2. Verify the following information: a. Initial (static) timing on the emissions plate agrees with the value displayed by V-MAC II. b. ECONOVANCE is approximately 5 inches long.

If the information matches but the timing is still too advanced, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If the information does not match, V-MAC II is trying to use a data file which may not match the engine hardware’s capabilities (static timing and timing range). Change the hardware to match the hardware requirements of the data file and attach the proper emissions plate, or download the correct data file for this engine. Retest to be sure the problem has been corrected.

If the current is between 0.6 and 0.9 amps, proceed to Test 37.

If the current to the timing control valve is above the range of 0.9 to 1.1 amps, proceed to Test 36.

If the current to the timing control valve is less than 0.6 amps, but greater than 0 amps, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If the current to the timing control valve is 0 amps, verify that there is power to the V-MAC II module.

If there was no power to the V-MAC II module, restore power and retest. If there was power, and the current was 0, replace the V-MAC II module.

Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 3-5 (ADVANCED) Test 21 Checking for improperly installed timing control valve gasket

If the static timing is incorrect by more than 1 degree, and the static timing was correct in Test 1 of the Basic Mechanical Section, the ECONOVANCE is sticking. Repair or replace the ECONOVANCE. Retest to be sure the problem has been corrected.

If Test 1 of the Basic Mechanical Section showed that the static timing was incorrect by more than 1 degree and had to be reset, and the static timing status still indicates that the timing is still too advanced, the ECONOVANCE is sticking. Repair or replace the ECONOVANCE. Retest to be sure the problem has been corrected.

Otherwise, proceed to Test 47.

Test 36 Checking the timing valve retainer plate 1. Visually inspect the timing control valve for signs of oil leakage between the round valve body and the housing or from the wiring.

Figure 155 — Checking Timing Control Valve Gasket

1. Turn the ignition key to the OFF position.

2. Remove the timing control valve assembly from the ECONOVANCE. 3. Inspect the gasket for proper installation.

If the gasket is installed properly, proceed to Test 42.

If the gasket is not installed properly, clean the timing valve oil supply filter. Correctly install a new gasket. Reinstall the timing control valve.

Retest to be sure the problem has been corrected.

Test 23 Checking for a stuck ECONOVANCE 1. Turn the ignition key to the OFF position.

2. Recheck the static timing (See Setting Engine Timing Section).

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If there is a leak, replace the entire control valve assembly.

If there is no leak, continue with the next step.

2. Grasp the round valve body and attempt to turn it using light force.

If the valve body can be turned with a light force, clean the front portion of the control valve and retainer plate and remove the plate. Examine the contact area of the plate and valve for signs of wear (DO NOT REMOVE THE VALVE FROM THE ASSEMBLY). If the valve is worn around the entire circumference, replace the complete timing control valve assembly. If only a portion of the valve circumference is worn, rotate the valve body so that the worn portion will not be touching a new retention plate. Install a new retention plate, using Loctite 242 on the plate bolts. Retest to be sure the problem has been corrected.

If there is no oil leakage and the valve body cannot be turned with light force, proceed to Test 72.

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DIAGNOSTIC CODE 3-5 (ADVANCED) Test 37

Test 42

Checking for wrong target, bad data file or V-MAC II module

Checking for a blocked oil drain holes and filters

1. Use the diagnostic tool (Pro-Link or PC) to display the engine model, data file part number and static timing.

2. Verify the following information: a. The engine model listed on the emissions plate agrees with the engine model displayed in V-MAC II. b. Initial (static) timing on the emissions plate agrees with the value displayed in V-MAC II. c. ECONOVANCE is approximately 5 inches long.

If the information matches but the timing is still too advanced, replace the V-MAC II module.

Retest to be sure the problem has been corrected.

If the information does not match, V-MAC II is trying to use a data file which may not match the engine hardware’s capabilities (static timing and timing range). Change the hardware to match the hardware requirements of the data file and attach the proper emissions plate, or download the correct data file for this engine. Retest to be sure the problem has been corrected.

Figure 156 — Timing Control Valve Drain Holes and Filters

1. Check the ECONOVANCE drain hole for blockage. Clean if needed.

2. Check the ECONOVANCE oil supply hole for blockage. Clean if needed.

3. Remove the secondary filter in the timing control valve body if equipped. Check the passage in the valve body for blockage.

Clean the secondary filter if needed.

Reinstall the secondary filter.

4. Clean the valve oil supply filter. Correctly install a new gasket. Reinstall the timing control valve. Retest to be sure the problem has been corrected. If the timing is still too advanced, replace the timing control valve and gasket.

If this test is being conducted at high idle, retest with the new timing valve.

If after retesting, the timing is still too advanced after the timing valve has been replaced, the ECONOVANCE seals should be replaced. The original timing control valve was not defective and should be reinstalled. Refer to the E7 Engine Service Manual for instructions on how to replace the ECONOVANCE seals.

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DIAGNOSTIC CODE 3-5 (ADVANCED) Test 47

Test 144

Checking for a potential V-MAC II module problem

Checking for blocked oil supply holes and filters

1. Replace the V-MAC II module with a new module, or with a module from another truck.

DO NOT REPROGRAM THE MODULE AT THIS TIME. 2. With the timing valve still disconnected, run the engine at 800 rpm for at least 30 seconds and record the timing using the diagnostic tool (Pro-Link or PC).

If the timing on the diagnostic tool is the same as the static timing (within 1 degree), the original V-MAC II module was defective. Program a new V-MAC II module. Retest to be sure the problem has been corrected.

If the timing is not the same as the static timing, reinstall the original V-MAC II module. A potential flywheel problem exists. Call Service Engineering.

Test 72 Checking for improperly installed timing control valve gasket 1. Turn the ignition key to the OFF position.

2. Remove the timing control valve assembly from the ECONOVANCE. 3. Inspect the gasket for proper installation.

If the gasket is installed properly, proceed to Test 144.

If the gasket is not installed properly, clean the valve oil supply filter. Correctly install a new gasket. Reinstall the timing control valve. Retest to be sure the problem has been corrected.

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Figure 157 — Timing Control Valve Drain Holes and Filters

1. Check the ECONOVANCE oil supply hole for blockage. Clean if needed.

2. Clean the valve oil supply filter. Check that the supply passage way is clear.

3. Remove the secondary filter in the timing control valve body if equipped. Check the passage in the valve body for blockage.

Clean the secondary filter if needed.

Reinstall the secondary filter.

4. Correctly install a new gasket. Reinstall the timing control valve. Retest to be sure the problem has been corrected.

If the timing is still retarded and the pressure is much lower than the gallery pressure, replace the timing control valve and gasket. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 4-1, 4-2 OR 4-3 DIAGNOSTIC BLINK CODE 4-1, 4-2 OR 4-3 MPH (ROAD SPEED) SENSOR TESTS DIAGNOSTIC CODE 4-1, 4-2 OR 4-3

Figure 158 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

4-1

4-2

4-3

PID

84

84

84

FMI

4

3

8

MID

142

142

142

Name

MPH (Road Speed) Sensor

MPH (Road Speed) Sensor

MPH (Road Speed) Sensor

Failure

Voltage below normal or shorted low

Voltage above normal or shorted high

Abnormal frequency, pulse width or period

SID

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DIAGNOSTIC CODE 4-1, 4-2 OR 4-3 Test 1

Test 3

Checking for an open, shorted or inactive sensor

Checking for an open in the sensor

1. Make certain that the ignition key is in the ON position.

2. Determine which fault the V-MAC II module has logged with regard to the MPH sensor.

If the V-MAC II module logged a short (code 4-1), proceed to Test 2.

If the V-MAC II module logged an open (code 4-2), proceed to Test 3.

If the V-MAC II module logged an inactive condition (code 4-3), make sure the sensor is adjusted to the proper setting. For proper adjustment, turn the sensor in by hand until it bottoms. Then back it out exactly 1 turn. Torque the jam nut to 15 lb-ft (20 N•m). If the sensor is adjusted properly and the fault is still active, move the vehicle a short distance. If the fault is still active, replace the sensor and move the vehicle again. Retest to be sure the problem has been corrected.

Test 2 Checking for a short to ground 1. Disconnect the MPH sensor at the sensor connector.

If the V-MAC II module now registers an open (code 4-2), proceed to Test 4.

If code 4-2 is not active, proceed to Test 5.

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Figure 159 — Resistance between Pins A and B

1. Turn the ignition key to the OFF position and disconnect the MPH sensor from the harness.

2. Measure the resistance between harness connector pins A (the signal [+] line) and B (the ground [−] line).

If the resistance is between 200 and 300 ohms, proceed to Test 6.

If the resistance is not between 200 and 300 ohms, repair the connector or replace the MPH sensor. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 4-1, 4-2 OR 4-3 Test 4

1. Turn the ignition key to the OFF position.

Checking for a short in the sensor

2. Disconnect the J1A connector from the V-MAC II module.

3. Check for continuity between J1A connector pins H3 (the MPH sensor PLUS [+] line) and G3 (the MPH sensor MINUS [−] line).

If there is continuity, locate and repair the short in the harness. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 10.

Test 6 Checking the voltage in the harness Figure 160 — MPH Sensor

1. Visually inspect the MPH sensor for a repairable short to ground on harness connector pin B.

If there is a repairable condition, repair the connector or replace the MPH sensor. Retest to be sure the problem has been corrected.

If there is not a repairable condition, replace the MPH sensor. Retest to be sure the problem has been corrected.

Figure 162 — Voltage between Pins A and B

1. Turn the ignition key to the ON position.

Test 5 Checking for continuity on the MPH PLUS (+) and MPH MINUS (−) lines

2. Measure the voltage between harness connector pins A (the signal [+] line) and B (the ground [−] line) on the sensor side of the connector.

If the voltage is greater than 4.0 volts, proceed to Test 13.

If there is no voltage, proceed to Test 12.

Figure 161 — Continuity between Pins G3 and H3

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DIAGNOSTIC CODE 4-1, 4-2 OR 4-3 Test 10

Test 12

Checking for continuity in the harness

Checking for continuity in the harness

Figure 163 — Continuity from Pin H3 to Ground

1. Check for continuity from J1A connector pin H3 (the MPH sensor PLUS [+] line) to a good ground.

Figure 164 — Jumper between Pins A and B

If there is continuity, locate and repair the short in the harness. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 20.

Figure 165 — Continuity between Pins G3 and H3

1. Turn the ignition key to the OFF position.

2. Connect a jumper between harness connector pins A and B, on the harness end of the connector.

3. Disconnect the J1A connector from the V-MAC II module.

4. Check for continuity between J1A connector pins H3 (the MPH sensor PLUS [+] line) and G3 (the MPH sensor MINUS [−] line).

If there is continuity, proceed to Test 24.

If there is no continuity, proceed to Test 25.

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DIAGNOSTIC CODE 4-1, 4-2 OR 4-3 Test 13 Checking the voltage on the MPH PLUS (+) line

1. Disconnect the J1B and J2 connectors from the V-MAC II module.

2. Check for continuity between J1A connector pin H3 (the MPH sensor PLUS [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is a short, locate and repair the short in the harness. Retest to be sure the problem has been corrected.

If there is no short, proceed to Test 40.

Test 24 Figure 166 — Voltage from Pin H3 to Ground

Checking the resistance in the harness

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A and J1B connectors from the V-MAC II module.

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1A connector pin H3 (the MPH sensor PLUS [+] line) to a good ground.

If the voltage is greater than zero volts, locate and repair the short to voltage in the harness. Retest to be sure the problem has been corrected.

Figure 168 — Resistance between Pins G3 and H3

1. Disconnect the jumper between harness connector pins A and B.

If the voltage is not greater than zero volts, proceed to Test 26.

2. Reconnect the sensor.

Test 20

3. Measure the resistance between J1A connector pins H3 (the MPH PLUS [+] line) and pin G3 (the MPH MINUS [−] line).

Checking for continuity in the harness

If the resistance is less than 500 ohms, proceed to Test 48.

If there is no resistance, locate and repair the open in the sensor connector. Retest to be sure the problem has been corrected.

Figure 167 — Continuity between Pin H3 and All Other Pins

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DIAGNOSTIC CODE 4-1, 4-2 OR 4-3 Test 25 Checking for an open in the MPH PLUS (+) line

1. Disconnect the jumper between harness connector pins A and B. 2. Disconnect the J1B connector from the V-MAC II module.

3. Connect a jumper between J1A connector pin H3 and J1B connector pin P2.

4. Check for continuity from harness connector pin A (the signal [+] line), on the harness end of the connector, to a good ground.

If there is continuity, repair the open in the MPH sensor MINUS [−] line (pin G3) on the J1A connector. Retest to be sure the problem has been corrected.

Figure 169 — Jumper between Pins H3 and P2

Figure 170 — Continuity from Pin A to Ground

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If there is no continuity, select another chassis ground. If there is still no continuity, repair the MPH PLUS [+] line (pin H3) on the J1A connector. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 4-1, 4-2 OR 4-3 Test 26

Test 40

Checking for continuity in the harness

Checking for a pin-to-pin short

Figure 171 — Continuity between Pin H3 and All Other Pins

Figure 172 — Continuity between Pin G3 and All Other Pins

1. Disconnect the serial link jumper.

2. Disconnect the J2 connector from the V-MAC II module.

3. Check for continuity between J1A connector pin H3 (the MPH sensor PLUS [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

4. Check for continuity between J1A connector pin G3 (the MPH sensor MINUS [−] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, repair the short in the harness between the pins which showed continuity. Retest to be sure the problem has been corrected.

Figure 173 — J1A, J1B and J2 Module Connectors

1. Visually inspect the V-MAC II module and module connectors for pin-to-pin shorts.

If there are any shorts, locate and repair the short at the V-MAC II connectors. Retest to be sure the problem has been corrected.

If there are no repairable shorts, replace the V-MAC II module or connectors. Retest to be sure the problem has been corrected.

If there is no continuity, replace the V-MAC II module. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 4-1, 4-2 OR 4-3 Test 48 Checking for a bad connection

1. Visually inspect both the harness and module sides of the V-MAC II module connectors for the cause of the open.

2. If no problem is found, clean the connector and reconnect the circuit.

If the problem no longer exists, check the connections at the sensor and module. Retest to be sure the problem has been corrected.

If the problem still exists, replace the V-MAC II module. Retest to be sure the problem has been corrected.

Figure 174 — J1A, J1B and J2 Module Connectors

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DIAGNOSTIC CODE 5-1 DIAGNOSTIC BLINK CODE 5-1 THROTTLE POSITION SENSOR (TPS) TESTS DIAGNOSTIC CODE 5-1

Figure 175 — Diagnostic Procedure Flowchart

Test 1 When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

5-1

PID

91

Checking for proper voltage on the voltage PLUS (+) line

SID FMI

4

MID

142

Name

Throttle Position Sensor (TPS)

Failure

Voltage below normal or shorted low

Figure 176 — Voltage from Pin A to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the TPS from the harness.

3. Turn the ignition key to the ON position.

4. Measure the voltage from harness connector pin A (the voltage reference [+] line), on the sensor end of the connector, to a good ground.

If the voltage is greater than 4.35 volts, proceed to Test 2.

If the voltage is less than 4.35 volts, proceed to Test 3.

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DIAGNOSTIC CODE 5-1 Test 2

Test 3

Checking for a shorted signal to ground in harness

Checking for continuity in the harness

Figure 177 — Continuity from Pin B to Ground

1. Turn the ignition key to the OFF position.

Figure 178 — Jumper from Pin A to Ground

2. Check for continuity from harness connector pin B (the ground [−] line) to a good ground.

If there is continuity, proceed to Test 5.

If there is no continuity, proceed to Test 4.

Figure 179 — Continuity from Pin L2 to Ground

1. Turn the ignition key to the OFF position.

2. Connect a jumper from harness connector pin A to a good ground.

3. Disconnect the J1B connector from the V-MAC II module.

4. Check for continuity from J1B connector pin L2 (the TPS voltage reference [+] line) to a good ground.

If there is continuity, proceed to Test 6.

If there is no continuity, try new ground points and retest. If there is still no continuity, locate and repair the open in the voltage reference [+] line (pin L2). Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 5-1 Test 4

Test 5

Checking for an open in the signal line in the harness

Checking for continuity to ground on the signal line

Figure 180 — Jumper between Pins A and B

Figure 182 — Continuity from Pin L1 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

3. Check for continuity from J1B connector pin L1 (the TPS signal [+] line) to a good ground.

If there is continuity, locate and repair the short to ground in the signal line. Retest to be sure the problem has been corrected.

Figure 181 — Continuity between Pins L1 and L2

If there is no continuity, proceed to Test 10.

1. Turn the ignition key to the OFF position.

2. Connect a jumper between harness connector pins A and B, on the harness side of the connector.

3. Disconnect the J1B connector from the V-MAC II module.

4. Check for continuity between J1B connector pins L1 (the TPS signal [+] line) and L2 (the TPS voltage reference [+] line).

If there is continuity, disconnect the jumper and proceed to Test 8.

If there is no continuity, locate and repair the open in the TPS signal line (pin L1) in the harness or connectors. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 5-1 Test 6

1. Turn the ignition key to the OFF position.

Checking for a short to ground in the voltage PLUS (+) line

2. Remove the jumper between harness connector pins A and B. 3. Disconnect the J1A and J2 connectors from the V-MAC II module.

4. Check for continuity between J1B connector pin L1 (the TPS signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

Figure 183 — Continuity from Pin L2 and Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the jumper from harness connector pin A to ground.

If there is continuity with another pin, locate and repair the short in the TPS signal line. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 16.

Test 10 Checking for a pin-to-pin short in the harness

3. Check for continuity from J1B connector pin L2 (the TPS voltage reference [+] line) to a good ground.

If there is continuity, locate and repair the short to ground in the TPS voltage reference [+] line in the harness or connector. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 12.

Test 8

Figure 185 — Continuity between Pin L1 and All Other Pins

Checking for a pin-to-pin short in the harness 1. Turn the ignition key to the OFF position.

2. Disconnect the J1A and J2 connectors from the V-MAC II module.

3. Check for continuity between J1B connector pin L1 (the TPS signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

Figure 184 — Continuity between Pin L1 and All Other Pins

If there is continuity with another pin, locate and repair the short in the TPS signal line. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 20.

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DIAGNOSTIC CODE 5-1 Test 12 Checking for a pin-to-pin short in the harness

1. Visually inspect both sides of the sensor connector for a repairable open in any of the pins.

If there is a repairable open, repair or replace the TPS connector. Retest to be sure the problem has been corrected.

If there is not a repairable open, continue with the next step.

Figure 186 — Continuity between Pin L2 and All Other Pins

1. Turn the ignition key to the OFF position.

2. Disconnect the J1A and J2 connectors from the V-MAC II module.

3. Check for continuity between J1B connector pin L2 (the TPS voltage reference [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, locate and repair the short to the voltage reference [+] line in the harness or connector. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 24.

Test 16 Checking for a fault in the sensor connector

2. Find the purple J 35616-4 male test lead from the J 38581 V-MAC jumper wire kit.

Align the male test lead with one of the rectangular female pins in the connector.

Gently push the test lead into the connector pin. Repeat this process for the remaining two female pins.

If any of the pins in the connector feel loose, repair or replace the connector. Retest to be sure the problem has been corrected.

If none of the pins in the connector feel loose, continue with the next step.

3. Find the purple J 35616-5 female test lead from the J 38581 V-MAC jumper wire kit.

Align the female test lead with one of the rectangular male pins in the Throttle Position Sensor connector. Gently push the test lead over the pin. Repeat this process for the remaining two male pins.

If any of the pins in the sensor feel loose, replace the Throttle Position Sensor or the connector.

Retest to be sure the problem has been corrected.

If none of the pins in the connector feel loose, proceed to Test 32.

Figure 187 — Inspect for an Open

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DIAGNOSTIC CODE 5-1 Test 20

Test 24

Checking for a repairable short on the V-MAC II module

Checking for an open or short in the V-MAC II module connector

Figure 188 — Inspect for a Short Around Pin L1

Figure 189 — Inspect for an Open Around Pin L2

1. Visually inspect the module side of the J1B connector for a short between the TPS signal line pin L1 and all adjacent pins.

1. Visually inspect the module side of the J1B connector for an open or short on pin L2 (the voltage reference [+] line).

If there is a repairable short, repair the short in the connector on the TPS signal line. Retest to be sure the problem has been corrected.

If there is a repairable condition, repair the short or open in the V-MAC II module connector. Retest to be sure the problem has been corrected.

If there is not a repairable short, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If there is not a repairable condition, reconnect the V-MAC II harnesses and the throttle position sensor connector. Turn the ignition key to the ON position. If the code 5-1 is still active, replace the V-MAC II module. If the fault is not active, check for loose connections in the sensor and module connectors. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 5-1 Test 32

Test 64

Checking for an open in the V-MAC II module

Checking for bad contact in the sensor connector 1. Reconnect the TPS. 2. Start the engine and flex the harness near the sensor.

If at any time the fault becomes inactive, repair or replace the sensor connector. Retest to be sure the problem has been corrected.

Figure 190 — Jumper between Pins A and B

Otherwise, replace the throttle position sensor.

Retest to be sure the problem has been corrected.

1. Connect a jumper between harness connector pins A and B. 2. Turn the ignition key to the ON position.

If the active fault changes from voltage low (code 5-1) to voltage high (code 5-2), proceed to Test 64.

If the active fault does not change, turn the ignition key to the OFF position. Check the V-MAC II module J1B connector for loose pins which could cause an open at the signal. Repair the open or replace the V-MAC II module. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 5-2 DIAGNOSTIC BLINK CODE 5-2 THROTTLE POSITION SENSOR (TPS) TESTS DIAGNOSTIC CODE 5-2

Figure 191 — Diagnostic Procedure Flowchart

Test 1 When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Checking for a change in the blink code with sensor removed 1. Turn the ignition key to the OFF position.

2. Disconnect the TPS.

Blink Code

5-2

PID

91

SID FMI

3

MID

142

Name

Throttle Position Sensor (TPS)

Failure

Voltage above normal or shorted high

Page 118

3. Turn the ignition key to the ON position.

If code 5-2 has changed to code 5-1, proceed to Test 2.

If the code has not changed, proceed to Test 3.

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DIAGNOSTIC CODE 5-2 Test 2

1. Turn the ignition key to the OFF position.

Checking the voltage on the pedal PLUS (+) line

2. Disconnect the J1B connector from the V-MAC II module.

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1B connector pin L1 (the TPS signal [+] line) to a good ground.

If the voltage is greater than 0.5 volts, the signal line is shorted to voltage in the harness or connector. Retest to be sure the problem has been corrected.

Figure 192 — Voltage from Pin A to Ground

1. Measure the voltage from harness connector pin A (the voltage reference [+] line) to a good ground.

If there is no voltage, proceed to Test 6.

Test 4 Checking for voltage on the ground line

If the voltage is greater than 5.25 volts, proceed to Test 5.

If the voltage is less than 5.25 volts, proceed to Test 4.

Test 3 Checking for the signal line shorted to voltage in the harness

Figure 194 — Voltage from Pin C to Ground

1. Measure the voltage from harness connector pin C (the ground [−] line) to a good ground.

If the voltage is greater than 0.5 volts, proceed to Test 9.

Figure 193 — Voltage from Pin L1 to Ground

If there is no voltage, proceed to Test 8.

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DIAGNOSTIC CODE 5-2 Test 5

Test 6

Checking for a short to voltage on the pedal PLUS (+) line

Checking for a pin-to-pin short on the signal line

Figure 195 — Voltage from Pin L2 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1B connector pin L2 (the TPS voltage reference [+] line) to a good ground.

If the voltage is greater than 0.5 volts, the pedal PLUS [+] line is shorted to more than 5.25 volts in the harness or at a connector. Retest to be sure the problem has been corrected.

If there is no voltage, proceed to Test 10.

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Figure 196 — Continuity between Pin L1 and All Other Pins

1. Disconnect the serial link jumper.

2. Disconnect the J1A and J2 connectors from the V-MAC II module.

3. Check for continuity between J1B connector pin L1 (the TPS signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, the signal line is shorted to more than 5.25 volts in the harness or at a connector. Locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, replace the V-MAC II module. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 5-2 Test 8 Checking for an open in the ground line

If the voltage is greater than 0.5 volts, the ground line is shorted to more than 5.25 volts in the harness or in the connectors. Locate and repair the short and replace the V-MAC II module.

Retest to be sure the problem has been corrected.

If there is no voltage, proceed to Test 18.

Test 10 Checking for a pin-to-pin short in the harness or V-MAC II module Figure 197 — Continuity from Pin C to Ground

1. Turn the ignition key to the OFF position.

2. Check for continuity from harness connector pin C (the ground [−] line) to a good ground.

If there is continuity, proceed to Test 16.

If there is no continuity, proceed to Test 17.

Figure 199 — Continuity between Pin L2 and All Other Pins

Test 9 Checking for a short to voltage in the harness

1. Disconnect the serial link jumper.

2. Disconnect the J1A and J2 connectors from the V-MAC II module.

3. Check for continuity between J1B connector pin L2 (the TPS voltage reference [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

Figure 198 — Voltage from Pin L3 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

If there is continuity with another pin, the TPS voltage reference [+] line is shorted in the harness or in the connectors. Retest to be sure the problem has been corrected.

If there is no continuity, replace the V-MAC II module. Retest to be sure the problem has been corrected.

3. Connect the serial link jumper into the serial communication port.

4. Measure the voltage from J1B connector pin L3 (the TPS ground [−] line) to a good ground.

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DIAGNOSTIC CODE 5-2 Test 16 Checking for a bad pedal connection 1. Reconnect the TPS. 2. Turn the ignition key to the ON position.

If code 5-2 is still active, proceed to Test 32.

If code 5-2 is not present, harness connector pin C is loose (either in the sensor or connector).

Repair the loose connection. Retest to be sure the problem has been corrected.

If there is now an active fault, code 5-1, there is poor contact in the sensor connector mating pins.

Repair the loose connections. Retest to be sure the problem has been corrected.

Test 17

1. Disconnect the J1B connector from the V-MAC II module.

2. Connect a jumper from harness connector pin C to a good ground.

3. Check for continuity from J1B connector pin L3 (the TPS ground [−] line) to a good ground.

If there is continuity, proceed to Test 34.

If there is no continuity, there is an open in the ground line in the harness. Locate and repair the open. Retest to be sure the problem has been corrected.

Test 18 Checking for pin-to-pin continuity with the ground line

Checking for an open in the ground line in the harness

Figure 202 — Continuity between Pin L3 and All Other Pins

1. Disconnect the serial link jumper.

2. Disconnect the J1A and J2 connectors from the V-MAC II module.

Figure 200 — Jumper from Pin C to Ground

3. Check for continuity between J1B connector pin L3 (the TPS ground [−] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, there is a pin-to-pin short between the TPS ground line and the pin which showed continuity. Locate and repair the short and replace the V-MAC II module.

Retest to be sure the problem has been corrected.

Figure 201 — Continuity from Pin L3 to Ground

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If there is no continuity, replace the V-MAC II module. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 5-2 Test 32

Test 34

Checking for a defective sensor

Checking for an open in the V-MAC II module or connector

1. Replace the TPS. 1. Reconnect the TPS and the J1B connector.

2. Turn the ignition key to the ON position.

2. Turn the ignition key to the ON position.

If code 5-2 is present, reinstall the original TPS and replace the V-MAC II module.

If code 5-2 is not present, replacing the TPS has solved the problem.

If code 5-2 is still present, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If code 5-2 is not present, the problem has been corrected. Recheck all connectors to ensure proper connections.

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DIAGNOSTIC CODE 5-3 DIAGNOSTIC BLINK CODE 5-3 FUEL CONTROL ACTUATOR TESTS DIAGNOSTIC CODE 5-3

Figure 203 — Diagnostic Procedure Flowchart

1. Turn the ignition key to the OFF position.

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

5-3

2. Disconnect the engine harness from the injection pump connector on the pump end of the harness.

3. Measure the resistance between Deutsch pins B and G, on the injection pump connector.

PID SID

4

FMI

5

MID

142

Name

Rack Actuator

Failure

Current below normal or open circuit

Test 1 Checking for an open in the actuator circuit

If the resistance is between 0.5 and 1.5 ohms, proceed to Test 2.

If the resistance is not between 0.5 and 1.5 ohms, continue with the next step.

4. Visually inspect the pins and crimps in the injection pump connector, at the pump end of the harness, for the cause of the open.

If there is a repairable condition, repair. Retest to be sure the problem has been corrected.

If there is not a repairable condition, send the pump to a certified pump shop for repair of the pump or integral jumper harness. Then retest to be sure the problem has been corrected.

Figure 204 — Resistance between Deutsch Pins B and G

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DIAGNOSTIC CODE 5-3 Test 2 Checking for an open in the harness

1. Disconnect the J1A and J1B connectors from the V-MAC II module.

2. Connect a jumper between J1A connector pins A2 and B1.

3. Check for continuity between Deutsch pins G and B, on the pump end of the harness.

4. Connect the jumper between J1A connector pins B2 and B3.

5. Check for continuity between Deutsch pins G and B, on the pump end of the harness.

Figure 205 — Jumper between Pins A2 and B1

If there is continuity in all tests, proceed to Test 4.

If there is no continuity in any of the tests, proceed to Test 5.

Figure 206 — Continuity between Deutsch Pins B and G

Figure 207 — Jumper between Pins B3 and B2

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DIAGNOSTIC CODE 5-3 Test 4

Test 5

Checking for an open on the pump end of the harness

Checking for an open in the actuator PLUS (+) line on the module end of the harness

Figure 208 — Resistance between Pins B1 and B3

1. Remove the jumpers between J1A connector pins A2 and B1 and J1A connector pins B2 and B3.

2. Reconnect the pump end of the harness to the injection pump connector.

Figure 209 — Jumper between Pin P2 and Either Pin B1 or Pin B2

3. Measure the resistance between J1A connector pins B1 (the fuel rack actuator PLUS [+] line) and B3 (the fuel rack actuator MINUS [−] line).

If the resistance is between 0.5 and 1.5 ohms, proceed to Test 8.

If the resistance is not between 0.5 and 1.5 ohms, the actuator PLUS [+] or MINUS [−] lines are open in the injection pump connector or the pump end of the harness. Repair the connector. Retest to be sure the problem has been corrected.

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Figure 210 — Continuity from Deutsch Pin G to Ground

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DIAGNOSTIC CODE 5-3 1. Connect a jumper between whichever pin did not show continuity in Test 2 (either pin B1 or B2), on the J1A connector, and J1B connector pin P2.

2. Check for continuity from Deutsch pin G, on the pump end of the harness, to a good ground.

If there is continuity, repair the open in the actuator MINUS [−] line which did not show continuity in Test 2 (A2 or B3 on the J1A connector). Retest to be sure the problem has been corrected.

If there is no continuity, select another chassis ground. If there is still no continuity, repair the actuator PLUS [+] line which did not show continuity in Test 2 (B1 or B2 on the J1A connector). Retest to be sure the problem has been corrected.

Test 8 Checking for a defective V-MAC II module or loose connector 1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

2. Turn the ignition key to the ON position.

If code 5-3 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no problems are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If code 5-3 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

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DIAGNOSTIC CODE 5-4 DIAGNOSTIC BLINK CODE 5-4 FUEL CONTROL ACTUATOR TESTS DIAGNOSTIC CODE 5-4

Figure 211 — Diagnostic Procedure Flowchart

Test 1 When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Checking for a defective module or injection pump 1. Turn the ignition key to the OFF position.

5-4

2. Disconnect the engine harness from the injection pump connector.

SID

4

3. Turn the ignition key to the ON position.

FMI

7

If the code changes to 5-3, proceed to Test 3.

MID

142

Name

Rack Actuator

Failure

Mechanical system not responding properly, or out of adjustment

Blink Code PID

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If the code does not change to code 5-3, replace the V-MAC II module. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 5-4 Test 3 Injection Pump Control Rod Adjustment

3. Note the position of the slot in the end of the adjustment screw. Then loosen the hex jam nut.

4. Using a small pocket-type screwdriver, turn the adjusting screw into the housing until it contacts the rack. Note the amount of rotation needed.

5. Back the adjusting screw out of the housing until it contacts the other side of the rack, noting the amount of rotation needed.

6. Finally, turn the adjusting screw halfway back into the housing to center it, by turning it back in exactly one-half of the total distance from fully in to fully out.

7. Tighten the jam nut and reinstall the hex acorn nut. Torque both to 9–11 lb-ft (12–15 N•m).

Figure 212 — Fuel Injection Pump

In rare cases, the injection pump control rod guide on the outboard side of the injection pump may be misadjusted, causing slower rack response. This can be adjusted using the following procedure:

8. Reconnect the engine harness to the injection pump. Retest to be sure the problem has been corrected.

If code 5-4 returns and the truck will not start, send the pump to a certified pump shop for repair.

Then retest to be sure the problem has been corrected.

1. Turn the ignition key to the OFF position.

2. Remove the hex acorn nut on the side of the pump. See illustration for location.

If code 5-4 does not return, this procedure has corrected the problem.

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DIAGNOSTIC CODE 5-5 DIAGNOSTIC BLINK CODE 5-5 FUEL CONTROL ACTUATOR TESTS DIAGNOSTIC CODE 5-5

Figure 213 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

5-5

PID SID

4

FMI

6

MID

142

Name

Rack Actuator

Failure

Current above normal or grounded circuit

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DIAGNOSTIC CODE 5-5 Test 1

Test 2

Checking for a short in the actuator circuit

Checking for a short to ground in the pump

Figure 214 — Resistance between Deutsch Pins B and G

1. Turn the ignition key to the OFF position.

2. Disconnect the engine harness from the injection pump connector on the pump end of the harness.

3. Measure the resistance between Deutsch pins B and G, on the injection pump connector.

Figure 215 — Continuity from Deutsch Pin B to Ground

1. Check for continuity from Deutsch pin B to a good ground.

If there is continuity, there is a short to ground inside the pump cover. Send the pump to a certified pump shop for repair of the pump actuator assembly. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 4.

If the resistance is between 0.5 and 1.5 ohms, proceed to Test 2.

If the resistance is not between 0.5 and 1.5 ohms, continue with the next step.

4. Visually inspect the pins and crimps in the injection pump connector, at the pump end of the harness, for the cause of the open.

If there is a repairable condition, repair. Retest to be sure the problem has been corrected.

If there is not a repairable condition, send the pump to a certified pump shop for repair of the pump or integral jumper harness. Then retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 5-5 Test 4

Test 8

Checking for a pin-to-pin short in the pump

Checking for a short to voltage in the harness

Figure 216 — Continuity between Deutsch Pin B and Deutsch Pins A, E and F

Figure 218 — Voltage from Pin B1 to Ground

Figure 219 — Voltage from Pin B2 to Ground Figure 217 — Continuity between Deutsch Pin G and Deutsch Pins A, E and F

1. Check for continuity between Deutsch pin B and Deutsch pins A, E, and F (one at a time) on the injection pump connector.

2. Repeat the test for Deutsch pin G and Deutsch pins A, E, and F (one at a time) on the injection pump connector.

If there is continuity between any of these pins, send the pump to a certified pump shop for repair of the pump or integral jumper harness. Retest to be sure the problem has been corrected.

Figure 220 — Voltage from Pin A2 to Ground

If there is no continuity, proceed to Test 8.

Figure 221 — Voltage from Pin B3 to Ground

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DIAGNOSTIC CODE 5-5 1. Disconnect the J1A and J1B connectors from the V-MAC II module.

2. Connect the serial link jumper into the serial communication port.

3. Measure the voltage on the J1A engine connector, from pins B1 and B2 (the actuator PLUS [+] lines) to a good ground.

4. Measure the voltage on the J1A engine connector, pins A2 and B3 (the actuator MINUS [−] lines) to a good ground.

Figure 224 — Voltage from Pin A2 to Ground

If the voltage on either line is greater than 0.5 volts, that line is shorted to another line in the harness. Locate and repair the short. Retest to be sure the problem has been corrected.

If the voltage on both lines is less than 0.5 volts, proceed to Test 16.

Test 16 Checking for a pin-to-pin short in the harness

Figure 225 — Voltage from Pin B3 to Ground

1. Disconnect the serial link jumper.

2. Disconnect the J2 connector from the V-MAC II module.

3. Check for continuity between J1A connector pin B1 (the actuator PLUS [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

Figure 222 — Voltage from Pin B1 to Ground

Do not check continuity from pin B1 to pin B2.

4. Check for continuity between J1A connector pin B2 (the actuator PLUS [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

Do not check continuity from pin B1 to pin B2.

Figure 223 — Voltage from Pin B2 to Ground

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DIAGNOSTIC CODE 5-5 5. Check for continuity between J1A connector pin A2 (the actuator MINUS [−] lines) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

Do not check continuity from pin A2 to pin B3.

6. Check for continuity between J1A connector pin B3 (the actuator MINUS [−] lines) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

1. Reconnect the pump end of the harness to the injection pump connector.

2. Measure the resistance between J1A connector pins B1 (the fuel rack actuator PLUS [+] line) and B3 (the fuel rack actuator MINUS [−] line).

If the resistance is between 0.5 and 1.5 ohms, proceed to Test 64.

If the resistance is not between 0.5 and 1.5 ohms, the actuator PLUS [+] or MINUS [−] lines are shorted or faulty in the injection pump connector or the pump end of the harness. Disconnect the connection and look for dirt or contamination which may cause the wires to short. Retest to be sure the problem has been corrected.

Do not check continuity from pin A2 to pin B3.

If there is continuity with another pin, repair the short in the harness between the pins which showed continuity. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 32.

Test 64 Checking for a defective V-MAC II module or loose connector 1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

2. Turn the ignition key to the ON position.

If there is continuity with J1B connector pins P1 and P2 (ground pins) or J2 connector pin F2, there may also be continuity with other pins.

Repair the short to pins P1, P2 and F2 first.

Retest to be sure the problem has been corrected.

Test 32 Checking for an open on the pump end of the harness

Figure 226 — Resistance between Pins B1 and B3

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If code 5-5 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no problems are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If code 5-5 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

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DIAGNOSTIC CODE 5-6 DIAGNOSTIC BLINK CODE 5-6 FUEL CONTROL ACTUATOR TESTS DIAGNOSTIC CODE 5-6

Figure 227 — Diagnostic Procedure Flowchart

Test 1 When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

5-6

PID SID

4

FMI

11

MID

142

Name

Rack Actuator

Failure

Failure mode not identifiable

An unexpected failure has occurred in the fuel rack actuator control system. This fault could be logged if there is insufficient voltage to the module.

Checking for adequate voltage out of the accessory relay 1. Turn the ignition key to the ON position.

2. Measure the voltage from the output of the accessory relay going to the electrical equipment panel to a good ground.

If the voltage is greater than 11 volts, or after correcting the low voltage problem the fault becomes active, proceed to Test 2.

If the voltage is less than 11 volts, the active fault may be caused by insufficient voltage at the module. Check battery and accessory relay connections, ground connections and proper accessory relay operation. If a problem is found and corrected, cycle the key for 5 seconds and check for an active fault again. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 5-6 Test 2

Test 8

Checking for a change in the code when the pump is disconnected

Checking for intermittent contact at the pump 1. Turn the ignition key to the OFF position.

1. Turn the ignition key to the OFF position.

2. Disconnect the engine harness from the injection pump connector on the pump end of the harness.

3. Turn the ignition key to the ON position.

If the code changes from 5-6 to 5-3, proceed to Test 4.

A 7-5 code should also be present.

If the code does not change from 5-6 to 5-3, contact Service Engineering.

Test 4 Checking for an intermittent open or short in the wiring 1. Turn the ignition key to the OFF position.

2. Reconnect the engine harness to the injection pump connector on the pump end of the harness.

3. Turn the ignition key to the ON position.

4. Flex the engine harness from the bulkhead to the injection pump connector and the pump jumper harness.

If, at any time, the fault goes from active to inactive while flexing the harness, there is an intermittent rack actuator open or short at that location in the harness. Contact Service Engineering before repairing the open or short.

If the fault does not go from active to inactive while flexing the harness, proceed to Test 8.

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2. Disconnect the engine harness from the injection pump connector on the pump end of the harness.

3. Examine the connector pins for evidence of dirt, wear, debris or intermittent contact.

If there is a repairable condition, repair the damage. Retest to be sure the problem has been corrected.

If there is no evidence of damage, proceed to Test 16.

Test 16 Checking for intermittent contact at the module 1. Disconnect the J1A and J1B connectors from the V-MAC II module.

2. Examine the connector pins for evidence of dirt, wear, foreign debris or intermittent contact.

If there is a repairable condition, repair the damage. Retest to be sure the problem has been corrected.

If there is no evidence of damage, proceed to Test 32.

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DIAGNOSTIC CODE 5-6 Test 32 Checking for good ground connections

1. Turn off all electrical devices in the truck, including dome lights.

2. Check the resistance from each of the module ground wires (J1B connector pins P1 and P2 and J2 connector pin F2) to the negative battery post.

If the resistance to the battery post is greater than 1 ohm, clean the connections between the module and battery ground. Reconnect the J1A and J1B connectors to the V-MAC II module.

Retest to be sure the problem has been corrected.

Figure 228 — Resistance from Pin F2 to Negative Battery Post

If the is resistance is less than 1 ohm or the fault is still active, proceed to Test 64.

Test 64 Checking for good battery and alternator POSITIVE connections 1. Clean the battery and alternator POSITIVE connections. Retest to be sure the problem has been corrected.

Figure 229 — Resistance from Pin P1 to Negative Battery Post

If the fault is still active, contact Service Engineering.

Figure 230 — Resistance from Pin P2 to Negative Battery Post

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DIAGNOSTIC CODE 5-7 OR 5-8 DIAGNOSTIC BLINK CODE 5-7 OR 5-8 DRIVER ALARM OUTPUT TESTS DIAGNOSTIC CODE 5-7 OR 5-8

Figure 231 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

5-7

5-8

SID

238

238

FMI

4

3

MID

142

142

Name

Driver Alarm Output

Driver Alarm Output

Failure

Voltage below normal or shorted low

Voltage above normal or shorted high

PID

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This diagnostic blink code is unique in that if the fault becomes active, the electronic malfunction lamp will turn ON until the ignition key is turned OFF, even if the electrical condition which caused the fault disappears.

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DIAGNOSTIC CODE 5-7 OR 5-8 Test 1 Checking the code 1. Verify which code is active.

If code 5-7 is active, proceed to Test 2.

If code 5-8 is active, proceed to Test 3.

If neither code is active, wiggle the harness and connectors to try to activate the code. Visually inspect the connectors for frayed, loose or corroded connections.

Test 2 Checking for continuous operation 1. Connect the Pro-Link 9000 or PC. 2. Turn the ignition key to the ON position.

If code 5-7 becomes active and the shutdown lamp and driver alarm stay ON continuously, proceed to Test 4.

If code 5-7 becomes active but the shutdown lamp and driver alarm do not stay ON continuously, proceed to Test 5.

If code 5-7 does not become active and either the shutdown lamp or driver alarm is inoperative, replace the inoperative component. Retest to be sure the problem has been corrected.

Test 3 Checking for continuous operation

3. Disconnect the coolant level sensor. This will activate code 1-7 and cause the V-MAC II module to attempt to turn the shutdown lamp ON. 4. After fault 1-7 has become active, reconnect the coolant level sensor.

5. After 30 seconds, observe the electronic malfunction indicator and Active Fault Table (in Service Diagnostics) to see if the lamp remains ON and the fault 5-8 remains active.

If the electronic malfunction lamp remains ON and fault 5-8 is active, proceed to Test 6.

If the electronic malfunction lamp does not remain ON and fault 5-8 is not active, the problem may be intermittent and hard to diagnose. Check the connections at the shutdown lamp and driver alarm and J1B connector for a short to voltage.

Retest to be sure the problem has been corrected.

Test 4 Checking for a short to ground 1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

3. Connect the serial link jumper into the serial communications port.

If the shutdown lamp and driver alarm come ON, there is a short to ground in the shutdown lamp and alarm signal [+] line. Proceed to Test 8.

If the shutdown lamp and driver alarm do not come ON, there is a short to ground in the V-MAC II module. Proceed to Test 9.

This diagnostic procedure will detect a short to voltage only if the module is attempting to turn the shutdown lamp and driver alarm ON. 1. Connect Pro-Link 9000 or PC. 2. Turn the ignition key to the ON position.

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DIAGNOSTIC CODE 5-7 OR 5-8 Test 5 Checking the power supply circuit Circuit 5-A-1.0 provides power to several gauges and indicators in the dash. An open or short to ground in this circuit may cause problems with these shared components. Some components powered by this circuit are: r

Multipurpose buzzer

r

Oil level indicator lamp

r

Malfunction indicator lamp

r

Parking brake warning lamp switch

If the voltage is greater than 0.5 volts, there is short to voltage. Proceed to Test 12.

If the voltage is less than 0.5 volts, proceed to Test 13.

Test 8 Short to ground isolation test

If there are electrical problems with other components in the dash, there may be an open or short to ground in circuit 5-A-1.0. Locate and repair the open or short to ground. Retest to be sure the problem has been corrected.

If there are no other obvious electrical problems with components in the dash, proceed to Test 10.

Figure 233 — Continuity between Pin R1 to All Other Pins

1. Disconnect the serial link jumper.

Test 6 Checking for a short to voltage

2. Remove the shutdown lamp bulb and disconnect the driver alarm buzzer.

3. Disconnect the J1A, J1B and J2 connectors from the V-MAC II module.

4. Check for continuity between J1B connector pin R1 (the shutdown lamp and alarm signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

Figure 232 — Voltage from Pin R1 to Ground

1. Turn the ignition key to the OFF position.

2. Remove the shutdown lamp bulb and disconnect the driver alarm buzzer.

3. Disconnect the J1B connector from the V-MAC II module.

4. Connect the serial link jumper into the serial communications port.

5. Measure the voltage from J1B connector pin R1 (the shutdown lamp and alarm signal [+] line) to a good ground.

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If there is another pin which shows continuity, J1B connector pin R1 is shorted to that pin. Locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 16.

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DIAGNOSTIC CODE 5-7 OR 5-8 Test 9

Test 12

Rechecking the blink code

Short-to-voltage isolation test

1. Turn the ignition key to the OFF position.

2. Reconnect the J1B connector.

3. Turn the ignition key to the ON position.

If code 5-7 is still active, check the V-MAC II module and connector J1B for dirt, loose or shorted pins or any other repairable damage. If no repairable conditions are found, replace the module. Retest to be sure the problem has been corrected.

If code 5-7 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

Test 10 Checking for battery voltage

Figure 235 — Continuity between Pin R1 and All Other Pins

1. Disconnect the serial link jumper.

2. Remove the shutdown lamp bulb and disconnect the driver alarm buzzer.

3. Disconnect the J1A, J1B and J2 connectors from the V-MAC II module.

4. Check for continuity between J1B connector pin R1 (the shutdown lamp and alarm signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is another pin which shows continuity, J1B connector pin R1 is shorted to the pin which showed continuity. Locate and repair the short.

Retest to be sure the problem has been corrected.

Figure 234 — Voltage from Pin R1 to Ground

1. Turn the ignition key to the OFF position.

If there is no continuity, J1B connector pin R1 is shorted to voltage somewhere else in the harness. Locate and repair the short to voltage.

2. Disconnect the J1B connector from the V-MAC II module.

3. Connect the serial link jumper into the serial communications port.

4. Measure the voltage from J1B connector pin R1 (the shutdown lamp and alarm signal [+] line) to a good ground.

If battery voltage is present, proceed to Test 20.

If no voltage is present, check circuit 5-A-0.8 for an open. If circuit 5-A-0.8 is not faulty, check circuit 5-A-1.0 for an open.

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DIAGNOSTIC CODE 5-7 OR 5-8 Test 13 Checking the V-MAC II module 1. Disconnect the serial link jumper.

2. Reconnect the J1B connector.

3. Install the shutdown lamp bulb and connect the driver alarm buzzer.

4. Turn the ignition key to the ON position.

If code 5-7 does not become active, the old lamp had a short to ground. Replacing the bulb has corrected the problem.

If code 5-7 is still active, there is a short to ground somewhere else in the harness. Locate and repair the short to ground. Retest to be sure the problem has been corrected.

Test 20 Checking J1B connector for an open

5. Disconnect the coolant level sensor. This will activate code 1-7 and cause the V-MAC II module to attempt to turn the shutdown lamp ON. 6. After fault 1-7 has become active, reconnect the coolant level sensor.

7. After 30 seconds, observe the electronic malfunction indicator and Active Fault Table (in Service Diagnostics) to see if the lamp remains ON and the fault 5-8 remains active.

Figure 236 — Visually Inspect Pin R1

If the electronic malfunction lamp goes ON and code 5-8 is active, check the V-MAC II module and connector for a repairable condition. If no repairable condition is found, replace the module.

Retest to be sure the problem has been corrected.

If the electronic malfunction lamp does not go ON, the procedures have corrected the problem.

Check all connectors to ensure proper connection.

Test 16 Checking for a failed unit

1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

3. Visually inspect J1B connector pin R1 for dirt, loose pins or deformed contacts.

4. Align the J 35616-2 male test lead (found in the J 38581 V-MAC jumper wire kit) with J1B connector pin R1. Gently push the test lead into pin R1 and check for looseness.

If a repairable open is found or the terminal feels lose, repair the J1B connector. Retest to be sure the problem has been corrected.

1. Disconnect the serial link jumper.

2. Reconnect the J1B connector.

3. Replace the shutdown lamp bulb with a bulb that is known to be good.

4. Turn the ignition key to the ON position.

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If the test lead is making good contact with J1B connector pin R1, proceed to Test 40.

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DIAGNOSTIC CODE 5-7 OR 5-8 Test 40 Checking the V-MAC II module 1. Turn the ignition key to the OFF position.

2. Reconnect the J1B connector.

3. Turn the ignition key to the ON position.

If code 5-7 becomes active, check the V-MAC II module for dirt. loose or broken pins or repairable damage. If no problems are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If code 5-7 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

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DIAGNOSTIC CODE 5-9 OR 5-10 DIAGNOSTIC BLINK CODE 5-9 OR 5-10 ELECTRONIC MALFUNCTION LAMP TESTS DIAGNOSTIC CODE 5-9 OR 5-10

Figure 237 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

5-9

5-10

SID

239

239

FMI

4

3

MID

142

142

Name

Fault Lamp Output

Fault Lamp Output

Failure

Voltage below normal or shorted low

Voltage above normal or shorted high

PID

Page 144

The electronic malfunction lamp will be unable to provide a diagnostic blink code while fault 5-9 or 5-10 is active.

If code 5-10 is active, the electronic malfunction lamp will be OFF and will remain OFF, even if a diagnostic code becomes active.

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DIAGNOSTIC CODE 5-9 OR 5-10 Test 1

Test 3

Checking the code

Checking for continuous operation

1. Verify which code is active.

If code 5-9 is active, proceed to Test 2.

If code 5-10 is active, proceed to Test 3.

If neither code is active, wiggle the harness and connectors to try to activate the code. Visually inspect the connectors and instrument cluster for frayed, loose or corroded connections.

Test 2 Checking for a short to ground

This diagnostic procedure will detect a short to voltage only if the module is attempting to turn the electronic malfunction lamp ON. 1. Connect Pro-Link 9000 or PC. 2. Turn the ignition key to the ON position.

3. Disconnect the coolant level sensor. This will activate code 1-7 and cause the V-MAC II module to attempt to turn the electronic malfunction lamp ON.

1. Connect the Pro-Link 9000 or PC. 2. Turn the ignition key to the ON position.

If code 5-9 becomes active and the electronic malfunction lamp stays ON continuously, proceed to Test 4.

If code 5-9 becomes active but the electronic malfunction lamp does not stay ON continuously, proceed to Test 5.

If code 5-9 is inactive and the electronic malfunction lamp stays ON continuously, there is an intermittent short to ground on circuit J1B-R2-0.8. Wiggle the harness and connectors to try to make the fault active.

4. After fault 1-7 has become active, reconnect the coolant level sensor.

5. Check the Active Fault Table (in Service Diagnostics) to see if code 5-10 is active.

If code 5-8 is active, proceed to Test 6.

If code 5-10 is not active, the problem may be intermittent and hard to diagnose. Check the connections at the shutdown lamp and driver alarm and J1B connector for a short to voltage.

If code 5-9 is inactive and the electronic malfunction lamp comes ON for 2 seconds and then goes out, the system is functioning properly and the problem may be intermittent. Check connector at the V-MAC II module and instrument cluster for secure connections.

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DIAGNOSTIC CODE 5-9 OR 5-10 Test 4

Test 6

Checking voltage at the V-MAC II module

Checking for a short to voltage

Figure 238 — Voltage from Pin R2 to Ground

Figure 239 — Voltage from Pin R2 to Ground

1. Turn the ignition key to the OFF position.

1. Turn the ignition key to the OFF position.

2. Connect the serial link jumper into the serial communications port.

2. Remove the electronic malfunction lamp bulb.

3. Measure the voltage from J1B connector pin R2 (the electronic malfunction lamp signal [+] line) to a good ground.

3. Disconnect the J1B connector from the V-MAC II module.

If battery voltage is present, proceed to Test 8.

If no voltage is present, proceed to Test 9.

Test 5 Checking the power supply circuit Circuit 5-A-1.0 provides power to several gauges and indicators in the dash. An open or short to ground in this circuit may cause problems with these shared components. Some components powered by this circuit are: r

Multi-purpose buzzer

r

Oil level indicator lamp

r

Malfunction indicator lamp

r

Parking brake warning lamp switch

If there are electrical problems with other components in the dash, there may be an open or short to ground in circuit 5-A-1.0. Locate and repair the open or short to ground. Retest to be sure the problem has been corrected.

If there are no other obvious electrical problems with components in the dash, proceed to Test 10.

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4. Connect the serial link jumper into the serial communications port.

5. Measure the voltage from J1B connector pin R2 (the electronic malfunction lamp signal [+] line) to a good ground.

If the voltage is greater than 0.5 volts, there is short to voltage. Proceed to Test 12.

If the voltage is less than 0.5 volts, proceed to Test 13.

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DIAGNOSTIC CODE 5-9 OR 5-10 Test 8 Checking the V-MAC II module for a short 1. Disconnect the serial link jumper.

2. Disconnect the J1B connector from the V-MAC II module.

3. Visually inspect the J1B connector for dirt, loose or shorted pins or any other repairable condition.

If a repairable condition exists, repair the damage. Retest to be sure the problem has been corrected.

If there is another pin which shows continuity, J1B connector pin R2 is shorted to that pin. Locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, J1B connector pin R2 is shorted to ground somewhere else in the harness. Locate and repair the short to ground.

Retest to be sure the problem has been corrected.

Test 10 Checking for an open

If there is not a repairable condition, replace the V-MAC II module or J1B connector. Retest to be sure the problem has been corrected.

Test 9 Short to ground isolation test

Figure 241 — Voltage from Pin R2 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

3. Connect the serial link jumper into the serial communications port.

Figure 240 — Continuity between Pin R2 and All Other Pins

1. Turn the ignition key to the OFF position.

2. Remove the electronic malfunction lamp bulb.

3. Disconnect the J1A, J1B and J2 connectors from the V-MAC II module.

4. Measure the voltage from J1B connector pin R2 (the electronic malfunction lamp signal [+] line) to a good ground.

If battery voltage is present, proceed to Test 20.

If no voltage is present, check circuit J1B-R2-0.8 for an open. If circuit J1B-R2-0.8 is not faulty, proceed to Test 21.

4. Check for continuity between J1B connector pin R2 (the electronic malfunction lamp signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

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DIAGNOSTIC CODE 5-9 OR 5-10 Test 12

Test 13

Short to voltage isolation test

Checking the V-MAC II module 1. Disconnect the serial link jumper.

2. Reconnect the J1B connector.

3. Install the electronic malfunction lamp bulb.

4. Turn the ignition key to the ON position.

Figure 242 — Continuity between Pin R2 and All Other Pins

1. Disconnect the serial link jumper.

2. Remove the electronic malfunction lamp bulb.

3. Disconnect the J1A, J1B and J2 connectors from the V-MAC II module.

4. Check for continuity between J1B connector pin R2 (the electronic malfunction lamp signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is another pin which shows continuity, J1B connector pin R2 is shorted to that pin. Locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, J1B connector pin R2 is shorted to voltage somewhere else in the harness. Locate and repair the short to voltage.

Retest to be sure the problem has been corrected.

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5. Disconnect the coolant level sensor. This will activate code 1-7 and cause the V-MAC II module to attempt to turn the shutdown lamp ON. 6. After fault 1-7 has become active, reconnect the coolant level sensor.

7. After 30 seconds, observe the electronic malfunction indicator and Active Fault Table (in Service Diagnostics) to see if the lamp remains ON and the fault 5-8 remains active.

If code 5-10 is active, check the V-MAC II module and connectors for a repairable condition. If no repairable condition is found, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If code 5-10 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connection.

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DIAGNOSTIC CODE 5-9 OR 5-10 Test 20

Test 21

Checking J1B connector for an open

Check supply voltage

Figure 243 — Visually Inspect Pin R2 Figure 244 — Jumper from Pin R2 to Ground

1. Disconnect the serial link jumper.

1. Disconnect the serial link jumper.

2. Disconnect the J1B connector from the V-MAC II module.

3. Visually inspect J1B connector pin R2 for dirt. loose pins or deformed contacts.

4. Align the J 35616-2 male test lead (found in the J 38581 V-MAC jumper wire kit) with J1B connector pin R1. Gently push the test lead into pin R2 and check for looseness.

If a repairable open is found or the terminal feels lose, repair the J1B connector. Retest to be sure the problem has been corrected.

If a repairable open is not found (the test lead is making good contact with J1B connector pin R2), proceed to Test 40.

2. Replace the electronic malfunction lamp bulb with a known good bulb.

3. Disconnect the J1B connector from the V-MAC II module.

4. Connect a jumper from J1B connector pin R2 to a good ground.

5. Connect the serial link jumper into the serial communications port.

If the electronic malfunction lamp turns ON, the old bulb was faulty and replacing the bulb has corrected the problem.

If the electronic malfunction lamp still does not turn ON, there is an open in supply circuit 5-A-1.0. Locate and repair the open. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 5-9 OR 5-10 Test 40 Checking the V-MAC II module 1. Disconnect the serial link jumper.

2. Reconnect the J1B connector.

3. Turn the ignition key to the ON position.

If code 5-9 becomes active, check the V-MAC II module for dirt. loose or broken pins or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If code 5-9 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

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DIAGNOSTIC CODE 6-5 DIAGNOSTIC BLINK CODE 6-5 BATTERY VOLTAGE TESTS DIAGNOSTIC CODE 6-5

Figure 245 — Diagnostic Procedure Flowchart

Test 2 When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

6-5

PID

168

SID FMI

1

MID

142

Name

Battery Voltage

Failure

Data valid, low voltage

Checking the system voltage with the engine running 1. Start the engine and let it idle.

2. Measure the voltage from the BATT stud on the electrical equipment panel to a good ground.

If the voltage is between 11.5 volts and 16.0 volts, proceed to Test 4.

If the voltage is not within the specified range, check the charging system for a malfunction.

Test 1 Checking the system voltage with the engine not running 1. With the engine not running, measure the voltage from the BATT stud on the electrical equipment panel to a good ground.

If the voltage is greater than 10.5 volts, proceed to Test 2.

If the voltage is less than 10.5 volts, locate and repair the cause for the low battery voltage.

Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 6-5 Test 4

If battery voltage is present, proceed to Test 8.

Checking for voltage at the V-MAC II module

If the voltage measured differs significantly from the voltage measured in Test 1, proceed to Test 9.

Test 8 Checking for an open ground circuit

Figure 246 — Voltage from Pin N1 to Ground

Figure 249 — Continuity from Pin P1 to Ground

Figure 247 — Voltage from Pin N2 to Ground

Figure 250 — Continuity from Pin P2 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

Figure 248 — Voltage from Pin N3 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

3. Measure the voltage from J1B connector pins N1, N2 and N3 (one at a time) to a good ground.

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3. Check for continuity from J1B connector pins P1 and P2 (one at a time) to a good ground.

If there is continuity on both pins, proceed to Test 16.

If there is a pin without continuity, check the suspect circuit for an open. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 6-5 Test 9 Checking for a pin-to-pin short

1. Turn the ignition key to the OFF position and remove fuse CB-20.

2. Disconnect the J1A, J1B and J2 connectors from the V-MAC II module.

3. Check for continuity between J1B connectors pins N1, N2 and N3 (one at a time) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is a pin with continuity, locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 18.

Figure 251 — Voltage from Pin N1 to Ground

Test 16 Checking for loose pins or a defective V-MAC II module 1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

Figure 252 — Voltage from Pin N2 to Ground

3. Visually inspect J1B connector pins N1, N2, N3, P1 and P2 for dirt, loose pins or deformed contacts.

4. Find the gray J 35616-2 male test lead from the J 38581 V-MAC jumper wire kit. Align the male test lead with J1B connector pin N1 and gently push the test lead into the connector pin. Repeat this process for J1B connector pins N2, N3, P1 and P2 (one at a time).

If there is a repairable open or terminals feel loose, repair or replace the J1B connector. Retest to be sure the problem has been corrected.

Figure 253 — Voltage from Pin N3 to Ground

If the test lead is making good contact with the J1B connector pins, proceed to Test 32.

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DIAGNOSTIC CODE 6-5 Test 18

Test 32

Checking for loose pins or a defective V-MAC II module

Checking the code 1. Turn the ignition key to the OFF position.

1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

2. Connect the J1B connector to the V-MAC II module.

3. Turn the ignition key to the ON position.

3. Visually inspect J1B connector pins N1, N2, N3, P1 and P2 for dirt, loose pins or deformed contacts.

4. Find the gray J 35616-2 male test lead from the J 38581 V-MAC jumper wire kit. Align the male test lead with J1B connector pin N1 and gently push the test lead into the connector pin. Repeat this process for J1B connector pins N2, N3, P1 and P2 (one at a time).

If there is a repairable open or terminals feel loose, repair or replace the J1B connector. Retest to be sure the problem has been corrected.

If the test lead is making good contact with the J1B connector pins, there is a problem somewhere else in the electrical system. Locate and repair the problem. Retest to be sure the problem has been corrected.

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If code 6-5 is still active, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If code 6-5 is not active, the procedures have corrected the problem. Check all connectors to ensure proper connections.

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DIAGNOSTIC CODE 6-6 DIAGNOSTIC BLINK CODE 6-6 INTERNAL COMMUNICATIONS TESTS DIAGNOSTIC CODE 6-6

Figure 254 — Diagnostic Procedure Flowchart

Test 1 When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

6-6

PID SID

254

FMI

12

MID

142

Name

Internal Module Communications

Failure

Bad intelligent device or component

This diagnostic determines if an internal V-MAC II module failure has occurred. The fault must be active when performing this procedure. The fault could be logged if there is insufficient voltage to the module.

Checking for adequate voltage out of the accessory relay 1. Turn the ignition key to the ON position.

2. Measure the voltage from the output of the accessory relay going to the electrical equipment panel to a good ground.

If the voltage is greater than 11 volts, or after correcting the low voltage problem the fault becomes active, proceed to Test 2.

If the voltage is less than 11 volts, the active fault may be caused by insufficient voltage at the module. Check battery and accessory relay connections, ground connections, and proper accessory relay operation. If a problem is found and corrected, cycle the key for 5 seconds and check for an active fault again. Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 6-6 Test 2

1. Turn the ignition key to the OFF position.

Checking for a damaged module connector

2. Disconnect the J1A, J1B and J2 module connectors from the V-MAC II module.

3. Visually inspect the harness and module sides of the V-MAC II module connectors to see if a repairable fault exists.

If there is a repairable fault, clean or repair the connector. Reconnect. Retest to be sure the problem has been corrected.

If there is not a repairable fault, replace the V-MAC II module or connectors. Retest to be sure the problem has been corrected.

Figure 255 — J1A, J1B and J2 Module Connectors

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DIAGNOSTIC CODE 7-1 DIAGNOSTIC BLINK CODE 7-1 SERVICE BRAKE SWITCH TESTS DIAGNOSTIC CODE 7-1

Figure 256 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

This fault becomes active when V-MAC II detects a large and sudden decrease in vehicle speed while in cruise or speed control modes without a service brake signal input.

7-1

PID SID

246

FMI

4

MID

142

Name

Brake Pedal Switch #1 (Service Brake)

Failure

Voltage below normal or shorted low

If this fault becomes active while on a chassis dynamometer, make the fault go inactive by applying the service brake for 1 second. Using a diagnostic tool (Pro-Link or PC), activate the Chassis Dynamometer Mode and rerun the dynamometer test. Once the test is completed, turn the ignition key to the OFF position for 3 seconds to restore the standard operating mode.

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DIAGNOSTIC CODE 7-1 Test 1

Test 3

Checking switch operation

Checking module connector

1. Using a diagnostic tool (Pro-Link or PC), check the status of the service brake switch as you engage and disengage the service brake with the ignition key in the ON position. Engage the service brake for at least 1 second.

If the service brake signal, displayed on the service tool, toggles properly and the fault is still active, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If the service brake signal, displayed on the service tool, toggles properly and the fault is inactive, proceed to Test 2.

If the service brake signal, displayed on the service tool, does not toggle properly, always remaining ON or remaining OFF, proceed to Test 3.

Test 2 Checking the MPH Sensor Adjustment

Figure 258 — J2 Module Terminals and Connector

1. Turn the ignition key to the OFF position.

2. Disconnect the J2 connector from the V-MAC II module.

3. Check both sides of the connector for problems such as bent, loose, missing or corroded pins.

Figure 257 — MPH Sensor

1. Check the MPH sensor adjustment. For proper adjustment, turn the sensor in by hand until it bottoms. Then back it out exactly 1 turn. Torque the jam nut to 15 lb-ft (20 N•m).

If the sensor is adjusted properly, drive the vehicle while monitoring road speed with a diagnostic tool (Pro-Link or PC).

If the road speed on the diagnostic tool is erratic, replace the MPH sensor. Retest to be sure the problem has been corrected.

If the road speed is not erratic, proceed to Test 4.

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If the pins are damaged, replace the connector pins or the V-MAC II module. Retest to be sure the problem has been corrected.

If the pins are in good condition, proceed to Test 6.

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DIAGNOSTIC CODE 7-1 Test 4 Checking brake switch connections 1. Check for good electrical connections at the brake switch. Also blow down the air tanks to remove any moisture which may have contaminated the switch to cause it to malfunction.

Test 6 Checking for stray voltage at the module

1. With the service brake engaged, measure the voltage from J2 connector pin B2 (the service brake signal [+] line) to a good ground.

If the voltage is greater than 10 volts, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If the voltage is less than 10 volts, proceed to Test 25.

Test 13 Checking for a short to voltage in the harness

Figure 259 — Voltage from Pin B2 to Ground

1. Turn the ignition key to the ON position.

2. With the service brake disengaged, measure the voltage from J2 connector pin B2 (the service brake [+] to a good ground.

If the voltage is greater than 0.5 volts, proceed to Test 13.

If the voltage is less than 0.5 volts, proceed to Test 12.

Test 12 Checking switch voltage at the module

Figure 261 — Voltage from Pin B2 to Ground

1. Turn the ignition key to the OFF position.

2. Disconnect the wire supplying 12 volts to the service brake switch.

3. Turn the ignition key to the ON position.

4. Measure the voltage from J2 connector pin B2 (the service brake signal [+] line) to a good ground.

If 12 volts are present, proceed to Test 27.

If 12 volts are not present, examine the service brake switch for bent or damaged pins that would cause a short to voltage. Repair the pins or replace the service brake switch. Retest to be sure the problem has been corrected.

Figure 260 — Voltage from Pin B2 to Ground

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DIAGNOSTIC CODE 7-1 Test 25

1. Turn the ignition key to the OFF position.

Checking for voltage to the switch

2. Disconnect the J1A and J1B connectors from the V-MAC II module.

1. Turn the ignition key to the OFF position.

2. Disconnect the wire leading from the service brake switch to the V-MAC II module at the switch terminal.

3. Turn the ignition key to the ON position.

4. Measure the voltage from J2 connector pin B2 (the service brake signal [+] line) to a good ground.

If 12 volts are present, proceed to Test 50.

If 12 volts are not present, there is a loss of power to the switch. Locate and repair the problem.

Retest to be sure the problem has been corrected.

3. Check for continuity between J2 connector pin B2 (the service brake signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, locate and repair the short in the harness. Retest to be sure the problem has been corrected.

If there is no continuity, there is a short to voltage somewhere else in the cab or dashboard between the service brake switch and the V-MAC II module. Locate and repair the short to voltage. Retest to be sure the problem has been corrected.

Test 50 Test 27 Checking for a short in the harness

Checking for proper switch operation 1. Turn the ignition key to the OFF position.

2. Engage the service brake.

3. Check for continuity across the two leads of the service brake switch.

If there is continuity, proceed to Test 100.

If there is no continuity, replace the switch. Retest to be sure the problem has been corrected.

Figure 262 — Continuity between Pin B2 and All Other Pins

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DIAGNOSTIC CODE 7-1 Test 100

Test 200

Checking for a short to ground

Checking for a short to ground in the switch 1. With the ignition key in the OFF position, check for continuity from either pin on the service brake switch to a good ground.

Engage and disengage the service brake.

If at any time there is continuity between the switch and ground, replace the service brake switch. Retest to be sure the problem has been corrected.

Figure 263 — Continuity from Pin B2 to Ground

1. Disconnect the J1A and J1B V-MAC II module connectors from the V-MAC II module.

If there is no continuity with ground, there is a break in the wire which supplies the service brake signal to J2 connector pin B2. Repair or replace the wire. Retest to be sure the problem has been corrected.

2. Check for continuity from J2 connector pin B2 (the service brake signal [+] line) to a good ground.

3. Check for continuity between J2 connector pin B2 (the service brake signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin or to ground, locate and repair the short in the harness. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 200.

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DIAGNOSTIC CODE 7-5 DIAGNOSTIC BLINK CODE 7-5 RACK POSITION SENSOR TESTS DIAGNOSTIC CODE 7-5

Figure 264 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

7-5

PID SID

3

FMI

5

MID

142

Name

Rack Position Sensor

Failure

Current below normal or open circuit

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DIAGNOSTIC CODE 7-5 Test 1 Checking for an open in the sensor in the pump

5. Visually inspect the pins and crimps in the injection pump connector, at the pump end of the harness, for the cause of the open.

If there is a repairable condition, repair. Retest to be sure the problem has been corrected.

If there is not a repairable condition, send the pump to a certified pump shop for repair of the pump or integral jumper harness. Retest to be sure the problem has been corrected.

Test 2 Checking for an open in the sensor in the pump

Figure 265 — Resistance between Deutsch Pins E and F

Figure 267 — Resistance between Deutsch Pins A and E

1. Measure the resistance between Deutsch pins A and E. Figure 266 — Resistance between Deutsch Pins A and F

1. Turn the ignition key to the OFF position.

If the resistance is between 30 and 50 ohms, proceed to Test 4.

2. Disconnect the engine harness from the injection pump connector.

If the resistance is not between 30 and 50 ohms, continue with the next step.

3. Measure the resistance between Deutsch pins F and E. 4. Measure the resistance between Deutsch pins A and F.

If the resistance for both checks is between 15 and 25 ohms, proceed to Test 2.

If the resistance is not between 15 and 25 ohms, continue with the next step.

2. Visually inspect the pins in the Deutsch connector (engine harness end) of the integral jumper harness for the cause of the open.

If there is a repairable condition, repair. Retest to be sure the problem has been corrected.

If there is not a repairable condition, send the pump to a certified pump shop for repair to the pump or integral jumper harness. Then retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 7-5 Test 4 Checking for an open in the harness

Figure 270 — Jumper from Deutsch Pin F to Ground

Figure 268 — Jumper from Deutsch Pin A and Ground

Figure 271 — Continuity between Pins K2 and P2 Figure 269 — Continuity between Pins J3 and P2

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DIAGNOSTIC CODE 7-5 1. Disconnect the J1A and J1B connectors from the V-MAC II module.

2. Connect a jumper, on the pump end of the engine harness, from Deutsch pin A to a good ground.

3. Check for continuity between J1A connector pin J3 (the rack position sensor signal [+] line) and J1B connector pin P2 (chassis ground).

Figure 272 — Jumper from Deutsch Pin E to Ground

4. Connect a jumper, on the pump end of the engine harness, from Deutsch pin F to a good ground.

5. Check for continuity between J1A connector pin K2 (the rack position sensor signal [+] line) and J1B connector pin P2 (chassis ground).

6. Connect a jumper, on the pump end of the engine harness, from Deutsch pin E to a good ground.

7. Check for continuity between J1A connector pin K1 (the rack position sensor signal [+] line) and J1B connector pin P2 (chassis ground).

If there is continuity on each pair tested, proceed to Test 8.

If there is no continuity, there is an open in the harness on the pair which did not show continuity.

Locate and repair the open. Retest to be sure the problem has been corrected.

Figure 273 — Continuity between Pins K1 and P2

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DIAGNOSTIC CODE 7-5 Test 8 Checking for an open in the pump connector

4. Measure the resistance between J1A connector pins K1 (the rack position sensor signal [+] line) and J3 (the rack position sensor signal [+] line).

5. Measure the resistance between J1A connector pins K2 (the rack position sensor signal [+] line) and J3 (the rack position sensor signal [+] line).

If the resistance is greater than 60 ohms in any pair, verify that there is no cause for this resistance at the bulkhead connector.

Figure 274 — Resistance between Pins K1 and K2

If the resistance is less than 60 ohms in each pair, proceed to Test 16.

If no cause is found, there is an open on the pair which showed high resistance (at the injection pump connector or on the injection pump end of the integral jumper harness). Locate and repair the open if possible.

The logical place for high resistance is in the engine harness end connector. Remove the wire in question and check for correct wire crimp. If no problem is found, look for a poor electrical contact between mating terminals.

Figure 275 — Resistance between Pins K1 and J3

Test 16 Checking for a defective V-MAC II module, or an open or loose connector 1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

2. Turn the ignition key to the ON position.

Figure 276 — Resistance between Pins K2 and J3

1. Remove the jumper on the pump end of the engine harness.

2. Reconnect the injection pump connector.

3. Measure the resistance between J1A connector pins K1 (the rack position sensor signal [+] line) and K2 (the rack position sensor signal [+] line).

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If code 7-5 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If code 7-5 is not active, there was an open at the injection pump connector, or on the injection pump end of the integral jumper harness. Inspect all connectors to ensure proper connections.

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DIAGNOSTIC CODE 7-6 DIAGNOSTIC BLINK CODE 7-6 RACK POSITION SENSOR TESTS DIAGNOSTIC CODE 7-6

Figure 277 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

7-6

PID SID

3

FMI

6

MID

142

Name

Rack Position Sensor

Failure

Current above normal or grounded circuit

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DIAGNOSTIC CODE 7-6 Test 1

Test 2

Checking for a short in the sensor in the pump

Checking for a short in the sensor in the pump

Figure 278 — Resistance between Deutsch Pins E and F

Figure 280 — Resistance between Deutsch Pins A and E

1. Measure the resistance between Deutsch pins A and E.

If the resistance is between 30 and 50 ohms, proceed to Test 4.

If the resistance is not between 30 and 50 ohms, send the pump to a certified pump shop for repair.

Retest to be sure the problem has been corrected.

Figure 279 — Resistance between Deutsch Pins A and F

1. Turn the ignition key to the OFF position.

2. Disconnect the engine harness from the injection pump connector.

3. Measure the resistance between Deutsch pins F and E. 4. Measure the resistance between Deutsch pins A and F.

If the resistance for both checks is between 15 and 25 ohms, proceed to Test 2.

If the resistance is not between 15 and 25 ohms, send the pump to a certified pump shop for repair.

Retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 7-6 Test 4 Checking for an internal short to ground, or voltage in the pump

Do not check continuity between Deutsch pins A, E and F.

If there is continuity with another pin, continue with the next step.

If there is no continuity, proceed to Test 8.

2. Visually inspect the pins and crimps in injection pump harness for the cause of the open.

If there is a repairable condition, repair. Retest to be sure the problem has been corrected.

Figure 281 — Continuity between Deutsch Pin A and Pins B, C, D, G, H and J (example)

1. Check continuity: Choose one of the following pins: Deutsch pin A, E or F. Check continuity between the pin you chose and each of the remaining pins (not including the original three selected) on the pump connector (one at a time). For example, if you choose pin A, check continuity between pin A and pins B, C, D, G, H, and J; but not between pin A and pins E or F. Also check continuity between the pin you chose and the case.

If there is not a repairable condition, send the pump to a certified pump shop for repair of the pump or integral jumper harness. Then retest to be sure the problem has been corrected.

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DIAGNOSTIC CODE 7-6 Test 8 Checking for a short to voltage on any rack position sensor line in the harness

1. Disconnect the J1A and J1B connectors from the V-MAC II module.

2. Connect the serial link jumper into the serial communication port.

3. Measure the voltage from J1A connector pin K1 (the rack position sensor signal [+] line) to a good ground.

4. Measure the voltage from J1A connector pin K2 (the rack position sensor signal [+] line) to a good ground.

Figure 282 — Voltage from Pin K1 to Ground

5. Measure the voltage from J1A connector pin J3 (the rack position sensor signal [+] line) to a good ground.

If the voltage is greater than 0.5 volts on any of the lines, locate and repair the short in the harness or connectors. Retest to be sure the problem has been corrected.

If the voltage is less than 0.5 volts on all of the lines, proceed to Test 16.

Figure 283 — Voltage from Pin K2 to Ground

Figure 284 — Voltage from Pin J3 to Ground

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DIAGNOSTIC CODE 7-6 Test 16 Checking for a pin-to-pin short in the harness

3. Check for continuity on the J1A connector, as follows: Check for continuity between J1A connector pin K1 (the rack position sensor signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors, except pins K2 and J3 on the J1A connector.

Next, check for continuity between pin K2 (the rack position sensor signal [+] line) and each of the other pins (one at a time) on all the connectors except pins K1 and J3 on the J1A connector.

Figure 285 — Continuity between Pin K1 and All Other Pins Except K2 and J3

Finally, check for continuity between pin J3 (the rack position sensor signal [+] line) and each of the other pins (one at a time) on all the connectors except pins K1 and K2 on the J1A connector.

If there is continuity with another pin, Deutsch connector pin A, E or F is shorted to ground in the harness or connector, or there is a pin-to-pin short in the harness or connector. Locate and repair the short to ground. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 32.

Figure 286 — Continuity between Pin K2 and All Other Pins Except K1 and J3

Test 32 Checking for a defective V-MAC II module 1. With the ignition key in the OFF position, reconnect the V-MAC II connectors.

2. Turn the ignition key to the ON position.

Figure 287 — Continuity between Pin J3 and All Other Pins Except K1 and K2

1. Disconnect the serial link jumper.

2. Disconnect the J2 connector from the V-MAC II module.

If code 7-6 is still active, check the V-MAC II module and connector for dirt, loose or broken pins, or repairable damage. If no repairable conditions are evident, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If code 7-6 is not active, the procedure has fixed the problem. Inspect all connectors to ensure proper connections.

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DIAGNOSTIC CODE 7-7 DIAGNOSTIC BLINK CODE 7-7 RACK POSITION SENSOR TESTS DIAGNOSTIC CODE 7-7

Figure 288 — Diagnostic Procedure Flowchart

Test 1 When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Blink Code

7-7

PID SID

3

FMI

11

MID

142

Name

Rack Position Sensor

Failure

Failure mode not identifiable

An unexpected failure has occurred in the rack position system. This fault could be logged if there is insufficient voltage to the module.

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Checking for adequate voltage out of the accessory relay 1. Turn the ignition key to the ON position.

2. Measure the voltage from the output of the accessory relay going to the electrical equipment panel to a good ground.

If the voltage is greater than 11 volts, or after correcting the low voltage problem the fault becomes active, proceed to Test 2.

If the voltage is less than 11 volts the active fault may be caused by insufficient voltage at the module. Check battery and accessory relay connections, ground connections, and proper accessory relay operation. If a problem is found and corrected, cycle the key for 5 seconds and check for an active fault again.

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DIAGNOSTIC CODE 7-7 Test 2

Test 8

Checking for a change in blink code when the pump is disconnected

Checking for intermittent contact at the pump 1. Turn the ignition key to the OFF position.

1. Turn the ignition key to the OFF position.

2. Disconnect the engine harness from the injection pump connector on the pump end of the harness.

3. Turn the ignition key to the ON position.

If the blink code changes from 7-7 to 7-5, proceed to Test 4.

2. Disconnect the engine harness from the injection pump connector on the pump end of the harness.

3. Examine the connector pins for evidence of dirt, wear, foreign debris or intermittent contact.

If there is a repairable condition, repair as needed. Retest to be sure the problem has been corrected.

A 5-3 code should also be present.

If there is no evidence of damage, proceed to Test 16.

If the blink code does not change from 7-7 to 7-5, contact Service Engineering.

Test 16

Test 4 Checking for an intermittent open or short in the wiring 1. Turn the ignition key to the OFF position.

2. Reconnect the engine harness to the injection pump connector on the pump end of the harness.

3. Turn the ignition key to the ON position.

4. Flex the engine harness from the bulkhead to the injection pump connector and the integral jumper harness.

Checking for intermittent contact at the module 1. Disconnect the J1A and J1B connectors from the V-MAC II module.

2. Examine the connector pins for evidence of dirt, wear, foreign debris or intermittent contact.

If there is a repairable condition, repair as needed. Retest to be sure the problem has been corrected.

If there is no evidence of damage, proceed to Test 32.

If, at any time, the fault goes from active to inactive while flexing the harness, there is an intermittent rack position sensor open or short at that location in the harness. Contact Service Engineering before repairing the open or short.

If the fault does not go from active to inactive while flexing the harness, proceed to Test 8.

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DIAGNOSTIC CODE 7-7 Test 32 Checking for good ground connections

1. Turn off all electrical devices in the truck, including dome lights.

2. Check the resistance from each of the module ground wires (J1B connector pins P1 and P2 and J2 connector pin F2) to the negative battery post.

If the resistance to the battery post is greater than 1 ohm, clean the connections between the module and battery ground. Reconnect the J1A and J1B connectors to the V-MAC II module.

Retest to be sure the problem has been corrected.

Figure 289 — Resistance from Pin F2 to Negative Battery Post

If the resistance is less than 1 ohm or the fault is still active, proceed to Test 64.

Test 64 Checking for good battery and alternator POSITIVE connections 1. Clean the battery and alternator POSITIVE connections. Retest to be sure the problem has been corrected.

Figure 290 — Resistance from Pin P1 to Negative Battery Post

Figure 291 — Resistance from Pin P2 to Negative Battery Post

Page 174

If the fault is still active, contact Service Engineering.

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SYMPTOM RELATED DIAGNOSTICS

SYMPTOM RELATED DIAGNOSTICS

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SYMPTOM RELATED DIAGNOSTICS BUFFERED MPH (SPEEDOMETER SIGNAL)

Figure 292 — Diagnostic Procedure Flowchart

Test 1 Checking for an external fault When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

1. Turn the ignition key to the OFF position.

2. Disconnect all external units at the buffered MPH external tie point (located near the accessory bus).

If a diagnostic blink code 4-3 is active, proceed to the MPH Sensor Diagnostic.

3. Test drive the vehicle.

If the speedometer is now working, there is a short in the external harness or component.

Locate and repair the short. Retest to be sure the problem has been corrected.

If the speedometer still does not work, proceed to Test 2.

This diagnostic procedure starts from a customer complaint that the speedometer is not working.

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SYMPTOM RELATED DIAGNOSTICS BUFFERED MPH (continued) Test 2

1. Turn the ignition key to the OFF position.

Checking for 12 volts and ground to speedometer

2. Disconnect the J1B connector from the V-MAC II module.

3. Disconnect the speedometer connector.

4. Connect the serial link jumper into the serial communication port.

5. On the harness side of the speedometer connector, check for 12 volts on the supply (power) line.

6. Disconnect the serial link jumper.

7. Check for continuity from the connector ground to a good ground.

If both supply and ground are present, proceed to Test 4.

If 12-volt supply or ground are not present, locate and repair the missing supply or ground. Retest to be sure the problem has been corrected.

Test 4 Checking for voltage on the buffered MPH line in the harness 1. Connect the serial link jumper into the serial communication port.

Figure 293 — Speedometer Connector

2. Measure the voltage on the buffered MPH line on the harness side of the speedometer connector.

If the voltage is greater than 0.5 volts, the buffered MPH line is shorted to voltage in the harness or connector. Repair the short and retest to be sure the problem has been corrected.

If the voltage is less than 0.5 volts, proceed to Test 8.

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SYMPTOM RELATED DIAGNOSTICS BUFFERED MPH (continued) Test 8 Checking for a pin-to-pin short or a short to ground in the harness

Figure 294 — Continuity between Pin W2 and All Other Pins

1. Disconnect the serial link jumper.

2. Check for pin-to-pin continuity from J1B connector pin W2 to each of the other pins (one at a time) of the J1B connector.

If there is continuity with another pin, the buffered MPH line is shorted to ground in the harness or at the connectors. Locate and repair the short.

Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 16.

Test 16 Checking for an open in the harness

Figure 296 — Speedometer Connector

1. Connect a jumper between J1B connector pins P1 and W2.

2. Check for continuity from the buffered MPH line, on the harness side of the speedometer connector, to a good ground.

If there is continuity, proceed to Test 32.

If there is no continuity, the buffered MPH line is open in the harness. Locate and repair the open.

Retest to be sure the problem has been corrected.

Figure 295 — Jumper between Pins P1 and W2

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SYMPTOM RELATED DIAGNOSTICS BUFFERED MPH (continued) Test 32

Test 64

Checking for proper voltage to the speedometer when the truck is moving

Checking for a loose connection 1. Reconnect the speedometer.

2. Test drive the vehicle.

If the speedometer is now working, testing has apparently corrected a loose connection.

Recheck all connectors to ensure proper connections.

If the speedometer is still not working, proceed to Test 128.

Test 128 Checking for a defective speedometer or V-MAC II module 1. Install a speedometer that is known to be good. Make sure the dip switches on the back of the speedometer are set properly.

2. Test drive the vehicle.

If the speedometer is now working, replacing the speedometer has corrected the problem.

If the speedometer is not working, reinstall the original speedometer and replace the V-MAC II module. Retest to be sure the problem has been corrected.

Figure 297 — Speedometer Connector

1. Remove the jumper between J1B connector pins P1 and W2.

2. Reconnect the J1B connector.

3. Turn the ignition key to the ON position.

4. Measure the voltage on the buffered MPH line on the speedometer connector while the vehicle is being driven at more than 10 mph.

If the voltage is between 1.75 and 3.25 volts, proceed to Test 64.

If the voltage is not within this range, replace the V-MAC II module. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS LOW COOLANT LEVEL

Figure 298 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Test 1 Checking lamp and alarm functions at start-up 1. Turn the ignition key to the ON position. The electronic fault lamp and engine shutdown lamp and alarm should all come ON for approximately 2 seconds and then go OFF.

If the electronic fault lamp does not come ON for approximately 2 seconds, follow the test procedures found in the Electronic Malfunction Lamp diagnostic procedure (code 5-9 or 5-10).

If the shutdown lamp and driver alarm do not come ON for approximately 2 seconds, follow the test procedures found in the Driver Alarm diagnostic (code 5-7 or 5-8).

If the electronic fault lamp comes ON but does not turn OFF, determine the blink code and proceed to that section of the manual. If there is no blink code, follow the test procedures provided in the Electronic Malfunction Lamp diagnostic (code 5-9 or 5-10).

If the shutdown lamp and driver alarm come ON but do not turn OFF, follow the test procedures found in the Driver Alarm diagnostic (code 5-7 or 5-8).

If the lamps and alarm work properly, proceed to Test 2.

Test 2 Checking lamp and alarm functions with low coolant 1. Drain some coolant from the radiator so that the coolant level is below the level on the probe.

If the fault lamp, shutdown lamp and driver alarm come ON, the system is working properly. Refill the radiator. Retest to be sure the problem has been corrected.

If the fault lamp, shutdown lamp and driver alarm do not come ON, proceed to Test 5.

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SYMPTOM RELATED DIAGNOSTICS LOW COOLANT LEVEL (continued) Test 5

1. Turn the ignition key to the OFF position.

Checking for voltage to the probe

2. Disconnect the J1A connector from the V-MAC II module.

3. Check for continuity from J1A connector pin F3 (the coolant level signal [+] line) to a good ground.

If there is continuity, locate and repair the short to ground in the wiring harness or connector.

Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 22.

Figure 299 — Voltage from Pin A to Ground

1. Turn the ignition key to the OFF position.

Test 22

2. Disconnect the harness from the coolant level sensor.

Checking for a pin-to-pin short in the harness

3. Turn the ignition key to the ON position.

4. Measure the voltage from pin A, on the harness end of the probe connector, to a good ground.

If the voltage is greater than 4 volts, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If the voltage is less than 4 volts, proceed to Test 11.

Test 11 Checking for a short to ground

Figure 301 — Continuity between Pin F3 and All Other Pins

1. Disconnect the J1B and J2 connectors from the V-MAC II module.

2. Check for continuity between J1A connector pin F3 (the coolant level signal [+] line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity with another pin, locate and repair the short in the wiring harness or connector. Retest to be sure the problem has been corrected.

Figure 300 — Continuity from Pin F3 to Ground

If there is no continuity, visually inspect the J1A connector for dirt, corrosion, or foreign matter around pin F3. If no problem is found, replace the V-MAC II module. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS r

When checking the harness, refer to the wiring diagrams in the appropriate Electrical Manual. Check each wire that connects the component to the V-MAC II module for shorts to ground, shorts to power or continuity with other wires. Check for continuity between both ends of the harness and each wire in the harness.

For general V-MAC II troubleshooting, follow the guidelines listed below:

r

All “ground check” tests should be performed with a known good ground.

r

Verify that the electronic fault and engine shutdown lights work properly. When the key is turned ON, both lamps should light for 2 seconds.

r

Continuity checks can not be performed if there is any current flowing. Before performing any continuity checks, make sure that:

r

Check for inactive faults, or active faults if the electronic malfunction lamp was replaced. (The Pro-Link retains information from the previous vehicle. Before looking for faults, reset the Pro-Link by activating the RESTART option on the Pro-Link menu.)

INTERMITTENT PROBLEMS This section of the manual is intended to provide troubleshooting tips for intermittent problems. In some instances there may not be a diagnostic blink code or inactive fault logged in the V-MAC II module to assist in troubleshooting.

r

Review the “Diagnostic Tools and Procedures” section at the front of this book.

r

Start troubleshooting at the sensor, switch, or other device. Then check the harness and finally check the V-MAC II module. Eliminate all other possible faults and repeat the procedure before replacing the V-MAC II module.

r

Check sensors, connectors and other components for broken pins, dirt, corrosion, loose terminals, excessive resistance, moisture and bad grounds.

r

If a sensor or other component is suspected as being bad, disconnect, clean and reconnect all terminals to that component.

Retest to see if the problem has been resolved.

r

If a sensor or other component is suspected as being bad, try to isolate it from the system. Often, when a faulty component is removed from the system, the vehicle performance will change. If performance does not change when the component is disconnected, that component may not be the source of the problem.

Page 182

– The ignition key is in the OFF position.

– The serial link jumper harness is not installed. r

Before disconnecting the harness to the V-MAC II module, the ignition key must be in the OFF position and the serial link jumper harness must not be installed. Failure to follow these instructions may result in internal electrical damage to the module.

r

Before turning the ignition key to the ON position with the J1B connector disconnected, always connect the serial link jumper into the serial communication port to provide keyed 12 volts. Turning the ignition key to the ON position with the J1B connector disconnected will not energize the accessory relay and will not provide a keyed 12 volts.

Turning the ignition key to the ON position with a sensor disconnected, or with the J1A connector disconnected while the J1B connector is still connected will result in an active fault. r

If the V-MAC II module is suspected of being defective, verify that there is power from the circuit breaker to the V-MAC II module.

r

Do not open the V-MAC II module or take any measurements at the V-MAC II module pins. If a module is suspected of being defective, visually inspect the pins for any repairable problems.

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SYMPTOM RELATED DIAGNOSTICS INTERMITTENT PROBLEMS (continued) r

As a final test before replacing the V-MAC II module, reconnect the module and confirm that the fault still exists.

r

If the V-MAC II module is replaced, verify that the new module has fixed the problem.

r

Do not reprogram a replacement V-MAC II module until verifying that it has fixed the problem.

Do not program a replacement V-MAC II module with MACK DATA PROGRAMMING until it is confirmed that replacing the V-MAC II module has corrected the problem. Reprogramming with MACK DATA PROGRAMMING executes a password protection function which assigns a new password to the vehicle. THIS PROCESS IS IRREVERSIBLE! If the old module was not the problem and is reinstalled on the vehicle, it cannot be reprogrammed because the password will no longer match.

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SYMPTOM RELATED DIAGNOSTICS LOW OIL PRESSURE WITH DRIVER ALARM

Figure 302 — Diagnostic Procedure Flowchart

Test 1

Test 4

Checking for oil level

Checking for oil pressure while cranking

1. Check the oil level on the dipstick.

If there is oil on the dipstick, proceed to Test 2.

If there is no oil on the dipstick, inspect the engine for the cause of the oil loss.

Test 2 Looking for missing oil fittings 1. Carefully inspect the engine for missing oil fittings. Look particularly around the turbo oil supply, the oil filter pedestal and the ECONOVANCE oil supply.

If there are no missing fittings, and no other obvious cause of pressure loss, proceed to Test 4.

Page 184

1. Turn the ignition key to the OFF position.

2. Connect a gauge that is known to be accurate to the oil pressure gallery or oil pedestal with a hose.

3. Disconnect the circuit breaker that supplies power from the electrical equipment panel to V-MAC II. 4. Turn the ignition key to the ON position and crank the engine.

If the gauge registers oil pressure within 30 seconds of cranking, proceed to Test 8.

If the gauge does not register oil pressure within 30 seconds of cranking, there is a problem with the oil pump drive, or other internal engine problem. Locate and repair the problem. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS LOW OIL PRESSURE WITH DRIVER ALARM (continued) Test 8

Test 17

Checking the pressure sensor

Electrical checks

1. Turn the ignition key to the OFF position.

1. Turn the ignition key to the OFF position.

2. Reinstall the circuit breaker.

2. Disconnect the engine harness from the oil pressure sensor.

3. Turn the ignition key to the ON position, start and idle the engine.

If the pressure exceeds 5 psi at idle, compare the pressure on the gauge with the pressure recorded by V-MAC II using a diagnostic tool. If the pressures agree within 3 psi, run the engine to high idle and compare the two pressures again. If the pressures still agree within 3 psi, there no longer is a problem. Retest to be sure the problem has been corrected.

If the pressure on the gauge does not reach or exceed 5 psi after 15 seconds of idling, STOP THE ENGINE. The oil pressure sensor works properly but there is still a mechanical problem resulting in low oil pressure, such as a blocked passage or filter. Locate and repair the problem.

Retest to be sure the problem has been corrected.

3. Measure the resistance from harness connector pin A (the ground [−] line) to a good ground.

If the resistance between the ground [−] line and ground is greater than 20 ohms, make sure that there are no electrical devices (lights, heater motors, etc.) running in the cab. Find a new good ground and try again. If the resistance is still greater than 20 ohms, there is a break or bad connection somewhere between the harness connector pin A and J1A connector pin G2.

Check for corroded terminals at the harness, bulkhead connector and J1A connector, and for evidence of damaged wiring.

If the resistance is less than 20 ohms, proceed to Blink Code 1-1 or 1-2 (Engine Oil Pressure Sensor).

If the pressures do not agree at any time within 3 psi, proceed to Test 17.

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SYMPTOM RELATED DIAGNOSTICS INCORRECT OIL PRESSURE VERSUS GAUGE

Figure 303 — Diagnostic Procedure Flowchart

Test 3 Electrical checks This diagnostic procedure is performed when the oil pressure recorded by V-MAC II (displayed on a diagnostic tool) does not agree with the oil pressure gauge in the cab.

Test 1 Checking the pressure gauge 1. Connect a gauge that is known to be accurate to the oil pressure gallery or oil pedestal with a hose.

2. Start and idle the engine.

3. Compare the pressure on the known good gauge with the pressure recorded by V-MAC II using a diagnostic tool.

If the pressures agree within 3 psi, the problem is with the gauge in the cab, or there is no problem.

If the pressures do not agree at anytime within 3 psi, proceed to Test 3.

Page 186

1. Turn the ignition key to the OFF position.

2. Disconnect the engine harness from the oil pressure sensor.

3. Measure the resistance from harness connector pin A (the ground [−] line) to a good ground.

If the resistance between the ground [−] line and ground is greater than 20 ohms, make sure that there are no electrical devices (lights, heater motors, etc.) running in the cab. Find a new good ground and try again. If the resistance is still greater than 20 ohms, there is a break or bad connection somewhere between the harness connector pin A and J1A connector pin G2.

Check for corroded terminals at the harness, bulkhead connector and J1A connector, and for evidence οf damaged wiring.

If the resistance is less than 20 ohms, proceed to Blink Code 1-1 or 1-2 (Engine Oil Pressure Sensor).

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SYMPTOM RELATED DIAGNOSTICS INJECTION PUMP RPM (ENGINE SPEED) SENSOR

Figure 304 — Diagnostic Procedure Flowchart

Test 2 This fault is found in the inactive fault table. This is a telltale fault. When it does appear in the active fault table, it only lasts a few seconds and then disappears without the Electronic Fault Lamp turning ON.

Checking the Customer Engine Overspeed setting 1. Using a diagnostic tool, check the CUSTOMER DATA PROGRAMMING section for the overspeed setting.

2. Check the inactive fault table and verify that the fault in question has not been logged.

This fault indicates that the engine speed exceeded the customer’s engine overspeed limit set in CUSTOMER DATA PROGRAMMING.

Test 1 Checking for proper RPM/TDC sensor adjustment 1. Check that the sensor is properly adjusted in the flywheel housing. For proper adjustment, refer to the Repair and Adjustment Procedures section.

3. Notify the vehicle owner or shop foreman that the engine had exceeded the company’s overspeed limit (do not notify the driver).

Report the number of occurrences as recorded by the inactive fault table. Obtain permission to clear the fault table.

4. Record on the Repair Order along with the number of occurrences. After servicing the vehicle, recheck the inactive fault table to be sure that the service procedures have not created more overspeed faults. If so, be sure to clear them before the truck leaves the shop.

If the sensor was properly adjusted, proceed to Test 2.

If the sensor was not properly adjusted, readjust the sensor. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS ENGINE BRAKE VERBAL COMPLAINT

Figure 305 — Diagnostic Procedure Flowchart

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Perform this diagnostic procedure when the engine brake does not work, does not turn OFF at the proper time or performs erratically.

Page 188

On some chassis models, pin 86 of the engine brake relay connector is connected to ground through the dash switch. On other models it is connected through V-MAC II. Check the wiring diagram supplied with the chassis.

This diagnostic assumes a particular wiring for the engine brake. Please review the diagram supplied with the chassis to verify the validity of each test step.

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SYMPTOM RELATED DIAGNOSTICS ENGINE BRAKE VERBAL COMPLAINT (continued) Test 1

Test 2

Testing for proper clutch switch operation

Checking resistance in the engine harness

Figure 306 — Testing Clutch Switch

1. Verify with a diagnostic tool that the clutch switch operates correctly and that there is approximately 1/2 inch of pedal travel before the clutch status reads “DISENGAGED”.

If the switch does not operate properly, refer to the Switch Diagnostics procedure found later in this section of manual and the Clutch Switch Adjustment procedure in the Repair and Adjustment Procedures section.

2. Once the clutch switch operates properly, test the engine brake.

If the brake works properly, the procedure has fixed the problem. Retest to be sure the problem has been corrected.

If the brake does not work properly, proceed to Test 2.

Figure 307 — Brake Relay Connector

1. Turn the ignition key to the OFF position.

2. Remove each brake relay from the relay connector.

Dynatard-equipped systems use one relay, while Jacobs Brakes normally use two relays.

3. Measure the resistance from pin 87 of each relay connector to a good ground.

If the resistance is between the specified range, proceed to Test 4.

If the resistance is not in the specified range, find another ground point and retest. If the resistance is still not in this range, proceed to Test 5.

Resistance Ranges (in Ohms) E7 Dynatard

E9 Dynatard

Jacobs Dual Relay

Jacobs Single Relay

4–6

2–3

9.7–14.3

4.8–7.2

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SYMPTOM RELATED DIAGNOSTICS ENGINE BRAKE VERBAL COMPLAINT (continued) Test 4

1. Turn the ignition key to the OFF position.

Checking for an open between the engine brake relay and the V-MAC II module

2. Disconnect the J1B connector from the V-MAC II module.

3. Check for continuity between J1B connector pin P3 (the engine brake control relay) and pins 85 and 86 on one engine brake relay connector.

If there is continuity between 85 or 86 (but not both) and P3, repeat the procedure for every other engine brake relay. If all of the relay test results return to this step, proceed to Test 8.

If there is no continuity, there is an open between either pin 85 and P3 or 86 and P3 (see the wiring schematic supplied with the vehicle). Locate and repair the open. Retest to be sure the problem has been corrected.

If there is continuity between BOTH pins and P3, the wires leading to pins 85 and 86 are shorted, or there is a short in the relay connector body.

Repair the short. Retest to be sure the problem has been corrected.

Figure 308 — Brake Relay Connector

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SYMPTOM RELATED DIAGNOSTICS ENGINE BRAKE VERBAL COMPLAINT (continued) Test 5

Test 8

Checking for proper connections inside the cylinder head cover

Checking for continuity through the switch

Figure 309 — Brake Electric Stud

1. Disconnect the engine harness from the brake electrical studs on the engine. Do not disconnect any wires which connect together the brake solenoids on different heads (jumper wires between heads are used with Dynatard).

2. Measure the resistance from the engine brake electrical studs on the cylinder heads to a good ground.

If the resistance is within the range specified in the table below, reconnect the engine harness to the head and proceed to Test 10.

If the resistance is not within this range, there is a bad electrical connection in one of the heads, or in one of the brake solenoids, or a bad solenoid ground.

Resistance Ranges (in Ohms) E7 Dynatard

E9 Dynatard

Jacobs Dual Relay

Jacobs Single Relay

*4–6

*2–3

9.7–14.3

*4.8–7.2

*If the resistance is double the specified range, the wire that connects the front and rear heads, or the left and right banks on the E9, may be open or has a bad connection.

Figure 310 — Brake Relay Connector

1. Turn the engine brake switch on the dashboard to the ON position. If the switch controls more than one brake relay, turn the switch so that all of the relays will be energized.

2. Check for continuity from pin 85, on the brake relay connector, to a good ground.

3. Check for continuity from pin 86, on the brake relay connector, to a good ground.

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SYMPTOM RELATED DIAGNOSTICS ENGINE BRAKE VERBAL COMPLAINT (continued) If the relay shows continuity to ground through pin 85 or pin 86, but not both, repeat the test with all remaining engine brake relays. If all of the relay test results lead to this step, proceed to Test 16.

If neither pin 85 or 86 show continuity to ground, proceed to Test 17.

Test 10

3. Check for continuity between J1B connector pin P3 (the engine brake relay control line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is no continuity, proceed to Test 32.

If pin P3 is shorted to any other pin in the harness, find and repair the short. Retest to be sure the problem has been corrected.

Checking for an open pressure switch

If the vehicle is not equipped with an inlet manifold pressure switch, proceed to Test 80.

Test 17 Checking for an open dash switch

1. Disconnect the inlet manifold pressure switch from the harness.

1. Remove the dashboard switch to expose the switch terminals.

2. With the ignition key in the OFF position, check for continuity across the switch terminals.

2. Locate the switch terminals leading to the relay which showed no continuity to ground in the previous test.

If there is continuity, proceed to Test 20.

If there is no continuity, replace the switch. Retest to be sure the problem has been corrected.

3. With the engine brake dash switch in the ON position, check for continuity across the switch terminals.

Test 16

If there is no continuity, replace the switch.

Retest to be sure the problem has been corrected.

Checking for a short to other wires

If there is continuity, proceed to Test 34.

Test 20 Checking for a short to ground in the pressure switch 1. Check for continuity from either of the pressure switch leads to a good ground.

Figure 311 — Continuity between Pin P3 and All Other Pins

1. Turn the engine brake switch on the dashboard to the OFF position.

2. Disconnect the J1A and J2 connectors from the V-MAC II module.

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If there is continuity, repair or replace the switch.

Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 40.

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SYMPTOM RELATED DIAGNOSTICS ENGINE BRAKE VERBAL COMPLAINT (continued) Test 32

Test 34

Checking for voltage at the relay pin 30

Checking for an open wire or switch connection

Figure 312 — Voltage from Pin 30 to Ground

1. Reconnect the V-MAC II module connectors.

2. Turn the ignition key to the ON position.

3. Measure the voltage from pin 30 of the brake relay connector to a good ground.

If the voltage on pin 30 is approximately 12 volts, repeat the test for all the remaining engine brake relay connector. If all of the test results return to this step, proceed to Test 64.

If the voltage on pin 30 is 0 volts, there is a short to ground or an open between the relay and the circuit breaker, or the circuit breaker has tripped.

Find and repair the problem. Retest to be sure the problem has been corrected.

Figure 313 — Continuity between Pins 85 and 86 and the Relay Side of the Dash

1. Check for continuity between the relay side of the dash switch connector and pin 85 and 86 on the brake relay connector which had no continuity to ground.

If there is continuity, the switch connection was bad. Check the switch for good connections.

Retest to be sure the problem has been corrected.

If there is no continuity, the wire leading from the switch to the relay has an open. Locate and repair the open. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS ENGINE BRAKE VERBAL COMPLAINT (continued) Test 40 Checking for an open or short in the harness 1. Reconnect the engine harness to the brake electrical studs on the engine.

2. Measure the resistance from pin A, on the harness side of the pressure switch connector between the switch and the solenoids, to a good ground.

If the resistance is within the range specified below, proceed to Test 80.

If the resistance is not in this range, there is an open or short to ground in the harness between the pressure switch and the cylinder head stud.

Locate and repair the open or short.

1. With the ignition key in the ON position, measure the voltage on one relay between pin 87 on the relay connector and a good ground.

If there is voltage on pin 87, locate and repair the short to voltage on the wire leading to pin 87 between the relay connector and the engine.

Retest to be sure the problem has been corrected.

If there is no voltage, repeat the procedure for each engine brake relay. If all of the relay test results lead to this step, proceed to Test 128.

Test 80 Checking for an open between the bulkhead connector and the engine or pressure switch

Resistance Ranges (in Ohms) E7 Dynatard

E9 Dynatard

Jacobs Dual Relay

Jacobs Single Relay

4–6

2–3

9.7–14.3

4.8–7.2

Test 64 Checking for voltage from other lines

1. Disconnect the bulkhead connector which contains the wire(s) that drive the engine brake solenoid (see schematic that came with the truck).

2. Measure the resistance from each engine brake bulkhead pin (one at a time) to a good ground.

If the resistance is within the range specified in the table below, there is an open or short between the bulkhead connector and the engine brake relay connector(s). Locate and repair the open or short. Retest to be sure the problem has been corrected.

If the resistance is not within the specified range, there is an open or short between the bulkhead connector and the engine brake solenoids, or if a pressure switch is used, between the bulkhead and the pressure switch. Locate and repair the open or short. Retest to be sure the problem has been corrected.

Resistance Ranges (in Ohms)

Figure 314 — Voltage from Pin 87 to Ground

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E7 Dynatard

E9 Dynatard

Jacobs Dual Relay

Jacobs Single Relay

4–6

2–3

9.7–14.3

4.8–7.2

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SYMPTOM RELATED DIAGNOSTICS ENGINE BRAKE VERBAL COMPLAINT (continued) Test 128 Checking for signal voltage from V-MAC

If the voltage on ONE of pins 85 OR 86 is 12 volts or more (but not both) while the engine decelerates, repeat this test with all of the remaining engine brake relays. If all of the relay test results lead to this step, proceed to Test 256.

If pin 85 AND pin 86 both measure 0 volts while the engine decelerates, proceed to Test 257.

Test 256 Checking for a bad brake relay connector

Figure 316 — Inspect for Corrosion, Shorts, Etc.

1. Turn the ignition key to the OFF position.

Figure 315 — Voltage from Pin 85 and 86 to Ground

1. Start the engine. Using the engine speed control ON/OFF and SET switches, set the engine speed to 1800 rpm.

2. Visually inspect each engine brake relay connector terminals for corrosion, shorts to other terminals, bent terminals or signs of poor contact.

2. Connect multimeter probes to pin 85 of one brake relay connector and to a good ground.

If there are visible problems, repair or replace the relay connector and test the engine brake operation.

3. While measuring the voltage between pin 85 and ground, turn the Speed Control ON/OFF switch to the OFF position. Record the voltage as the engine decelerates.

If there are no visible problems, reinstall the relay(s) and test the engine brake.

4. Repeat this procedure for pin 86 of the same engine brake relay connector.

If the engine brake works properly, the procedure has corrected the problem. Check all connections.

If the engine brake still does not work properly, proceed to Test 512.

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SYMPTOM RELATED DIAGNOSTICS ENGINE BRAKE VERBAL COMPLAINT (continued) Test 257

Test 512

Checking for engine brake disabling parameters

Checking for a failed relay

1. Using the engine speed control ON/OFF and SET buttons, set the engine speed to 1800 rpm.

2. Using a diagnostic tool (Pro-Link or PC), monitor the engine speed, fuel flow, throttle position and clutch switch status.

3. Turn the Speed Control ON/OFF switch to the OFF position.

As the engine decelerates, if the throttle position on the diagnostic tool indicates anything other than 0% throttle, there is a problem with the throttle pedal circuit. See Diagnostic Blink Code 5-2.

As the engine decelerates, if the fuel flow on the diagnostic tool indicates anything other than 0 fuel above 900 rpm, remove the injection pump and send it to a certified pump shop for repairs.

Retest to be sure the problem has been corrected.

As the engine decelerates, if the clutch switch status on the diagnostic tool indicates that the clutch was disengaged at any time, there is a problem in the clutch switch circuit. Check the clutch switch adjustment. Also see the Switch Diagnostics section.

If everything appears to be working properly, proceed to Test 514.

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1. Replace the engine brake relay with a new part and test the engine brake.

If the engine brake works properly, the old relay was bad and the new relay fixed the problem.

Retest to be sure the problem has been corrected.

If the engine brake does not work properly, the system appears to be electrically correct. Consult the E7 or E9 Service Manual for Dynatard troubleshooting procedures, or the Jacobs Brake Service Manual for Jake Brake troubleshooting procedures.

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SYMPTOM RELATED DIAGNOSTICS ENGINE BRAKE VERBAL COMPLAINT (continued) Test 514

1. Turn the ignition key to the OFF position.

Checking for bad connections at the V-MAC II module

2. Disconnect the J1B connector from the V-MAC II module.

3. Visually inspect both the harness and module sides of the connector for a bent or broken pin P3, or evidence of an open or short to ground around pin P3. Repair the damage if possible.

If there is no evidence of damage, continue with the next step.

4. Find the gray J 35616-2 male test lead from the J 38581 V-MAC jumper wire kit. Align the male test lead with the female pin P3 in the harness side of the J1B connector. Gently push the test lead into the connector pin, being careful to align the lead with the rectangular pin.

If the pin in the connector feels loose, repair or replace the pin in the connector. Retest to be sure the problem has been corrected.

If the pin does not feel loose, replace the V-MAC II module. Retest to be sure the problem has been corrected.

Figure 317 — Inspect for a Bent or Broken Pin Around Pin P3

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SYMPTOM RELATED DIAGNOSTICS BUFFERED RPM (TACH DRIVE OUTPUT)

Figure 318 — Diagnostic Procedure Flowchart

Test 2 When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

Checking for 12 volts and ground to tachometer 1. Turn the ignition key to the OFF position.

2. Disconnect the J1B connector from the V-MAC II module.

This diagnostic procedure starts from a customer complaint that the tachometer is not working.

Test 1 Checking for an external fault

3. Disconnect the tachometer connector.

4. Connect the serial link jumper into the serial communication port.

5. On the harness side of the tachometer connector, check for 12 volts on the supply line.

1. Turn the ignition key to the OFF position.

6. Disconnect the serial link jumper.

2. Disconnect all external units at the buffered RPM external tie point (located near the accessory bus).

7. Check for continuity from the tachometer ground line to a good ground.

3. Start the engine.

If the tachometer is now working, there is a short in the external harness or component. Locate and repair the short. Retest to be sure the problem has been corrected.

If the tachometer still does not work, proceed to Test 2.

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If both supply and ground are present, proceed to Test 4.

If 12-volt supply or ground are not present, locate and repair the missing supply or ground. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS BUFFERED RPM (continued) Test 4

Test 16

Checking for voltage on the buffered RPM line in the harness

Checking for an open in the harness

1. Connect the serial link jumper into the serial communication port.

2. Measure the voltage from the buffered RPM line on the harness side of the tachometer connector.

If the voltage is greater than 0.5 volts, the buffered RPM line is shorted to voltage in the harness or connector. Locate and repair the short. Retest to be sure the problem has been corrected.

Figure 320 — Jumper between Pins W3 and P1

If the voltage is less than 0.5 volts, proceed to Test 8.

1. Connect a jumper between J1B connector pins W3 and P1.

Test 8

2. Check for continuity from the buffered RPM line, on the harness side of the tachometer connector, to a good ground.

Checking for a pin-to-pin short or a short to ground in the harness

If there is continuity, proceed to Test 32.

If there is no continuity, the buffered RPM line is open in the harness. Locate and repair the open.

Retest to be sure the problem has been corrected.

Test 32 Checking for proper voltage to the tachometer when the engine is running Figure 319 — Continuity between Pin W3 and All Other Pins

1. Remove the jumper between J1B connector pins P1 and W2.

1. Disconnect the serial link jumper.

2. Reconnect the J1B connector.

2. Check for pin-to-pin continuity between J1B connector pin W3 and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

3. Turn the ignition key to the ON position.

If there is continuity with another pin, the buffered RPM line is shorted to ground in the harness or at the connectors. Locate and repair the short.

Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 16.

4. Measure the voltage from the buffered RPM line on the tachometer connector while the engine is running.

If the voltage is between 1.75 and 3.25 volts, proceed to Test 64.

If the voltage is not within this range, replace the V-MAC II module. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS BUFFERED RPM (continued) Test 64

Test 128

Checking for a loose connection

Checking for a defective tachometer or V-MAC II module

1. Reconnect the tachometer.

2. Run the engine.

If the tachometer is now working, testing has apparently corrected a loose connection.

Recheck all connectors to ensure proper connections.

If the tachometer is still not working, proceed to Test 128.

1. Replace the tachometer with a known good unit.

2. Run the engine.

If the tachometer is now working, the old tachometer is defective. Replace the old tachometer with a new unit. Retest to be sure the problem has been corrected.

If the tachometer is not working, reinstall the original tachometer and replace the V-MAC II module. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS ON/OFF FAN CONTROL VERBAL COMPLAINT

Figure 321 — Diagnostic Procedure Flowchart

Perform this diagnostic procedure when the ON/OFF fan drive does not turn ON, does not turn OFF, allows the engine to overheat, or the override switch does not work. This procedure should not be used for viscous fan drives or ON/ OFF fan drives which are not under V-MAC II control.

The ON/OFF fan drive is clutched using air pressure. The air pressure is controlled through an electrical circuit attached to V-MAC II. Electrically, when V-MAC II allows current to flow through the circuit the fan is DISENGAGED. When the electrical flow of current is interrupted the fan is ENGAGED. In this manner the fan is engaged if there is a loss of electrical power.

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SYMPTOM RELATED DIAGNOSTICS ON/OFF FAN CONTROL VERBAL COMPLAINT (continued) The operation on the pneumatic portion of the control depends on the type of fan clutch being used. r

r

For the KYSOR fan clutch, the fan is DISENGAGED and allowed to turn freely when air pressure is applied to the fan clutch. A loss of air pressure ENGAGES the fan.

For the HORTON fan clutch, the fan is ENGAGED and is locked when air pressure is applied to the fan clutch. A loss of air pressure DISENGAGES the fan.

The fan clutch type can be visually identified.

Kysor clutches are larger than a viscous clutch and attaches from the front of the fan. Horton clutches are about the same size as a viscous clutch with the fan attaching from the rear.

When performing electrical tests, it is important to wiggle wires and connectors to identify intermittent connection problems.

The fan can engage without warning. Hands, arms and personal items can easily be entangled in belts. Keep arms, hair, clothing and jewelry clear of the fan and belts when the engine is running.

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Test 1 Checking for voltage at the fan clutch solenoid 1. Turn the ignition key to the OFF position.

2. Disconnect the engine harness from the fan clutch solenoid connector.

3. Turn the ignition key to the ON position.

4. Measure the voltage from pin A of the fan clutch solenoid engine connector to a good ground.

If 12 volts are present, proceed to Test 2.

If 12 volts are not present, there is an open or short between pin A of the fan clutch solenoid engine connector and the circuit breaker, or the circuit breaker has failed. Repair the open and check the fan operation. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS ON/OFF FAN CONTROL VERBAL COMPLAINT (continued) Test 2

Test 4

Checking the energized solenoid operation

Checking the de-energized solenoid operation 1. Disconnect the jumper wire from pin B to ground (do not reconnect the solenoid connector).

2. With the coolant temperature less than 170°F (77°C) attempt to turn the fan by hand.

If the fan still turns freely, proceed to Test 9.

If the fan does not turn freely, proceed to Test 8.

Test 5 Checking for a failed fan clutch Figure 322 — Jumpers from Pin A to Pin A and Pin B to Ground

1. Disconnect the discharge air hose which runs from the solenoid to the fan clutch.

KYSOR FAN CLUTCH:

Never place hands near the fan or belts while the engine is running.

1. Turn the ignition key to the OFF position.

2. Connect a jumper between pin A of the engine connector and pin A of the solenoid connector.

3. Connect a jumper from pin B of the solenoid connector to a good ground.

4. Start the engine. Allow chassis air pressure to build up to at least 90 psi.

5. Stop the engine.

6. Turn the ignition key to the ON position.

7. With the coolant temperature less than 170°F (77°C) attempt to turn the fan by hand.

If the fan is disengaged and turns freely, proceed to Test 4.

If air flows out of the solenoid discharge port with the ignition key in the ON position, there is a problem with the fan clutch, or the hose running from the solenoid to the fan clutch is pinched or damaged. Locate and repair the problem. Retest to be sure the problem has been corrected.

If air does not flow out of the solenoid discharge port, proceed to Test 11.

HORTON FAN CLUTCH:

If air flows out of the solenoid discharge port, the valve may be plumbed improperly. Reverse the vent and air supply lines on the solenoid and retest. Verify that air does not flow out of the discharge port when the jumper wire is connected to ground, and that air flows when the jumper wire is removed. Retest to be sure the problem has been corrected.

If air does not flow out of the solenoid discharge port with the ignition key in the ON position, there is a problem with the fan clutch. Locate and repair the problem. Retest to be sure the problem has been corrected.

If the fan does not turn freely, proceed to Test 5.

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SYMPTOM RELATED DIAGNOSTICS ON/OFF FAN CONTROL VERBAL COMPLAINT (continued) Test 8

Test 9

Checking for voltage at the freon fan pressure switch

Checking for a failed fan clutch 1. Disconnect the air hose which runs from the solenoid to the fan clutch.

KYSOR FAN CLUTCH:

If air flows out of the solenoid discharge port, the solenoid is defective. Replace the solenoid and retest the fan operation.

If air does not flow out of the solenoid discharge port, there is a problem with the fan clutch.

Locate and repair the problem. Retest to be sure the problem has been corrected.

Figure 323 — Voltage from Pin B to Ground

HORTON FAN CLUTCH: 1. Turn the ignition key to the OFF position.

2. Reconnect the fan clutch solenoid to the engine harness.

3. Disconnect the freon fan pressure switch connector from the engine harness.

If air flows out of the solenoid discharge port, there is a problem with the fan clutch, or the hose running from the solenoid to the fan clutch is pinched or damaged. Locate and repair the problem. Retest to be sure the problem has been corrected.

4. Turn the ignition key to the ON position.

If air does not flow out of the solenoid discharge port, proceed to Test 19.

5. Measure the voltage from harness connector pin B (the freon fan pressure switch engine connector), leading back to the solenoid, to a good ground.

Test 11

If 12 volts are present, proceed to Test 16.

If 12 volts are not present, proceed to Test 17.

Checking for air supply — KYSOR only 1. Crack the air supply line leading to the solenoid.

If air flows out of the supply line, proceed to Test 22.

If air does not flow out of the supply line, there is a blockage in the supply line or some other air system problem. Locate and repair the problem.

Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS ON/OFF FAN CONTROL VERBAL COMPLAINT (continued) Test 16 Checking for proper freon fan pressure switch operation

4. Start the engine. Turn the air conditioning on HIGH with the doors open. Monitor the coolant temperature. Do not let the engine run long enough to exceed 190°F (88°C). If the freon fan pressure switch is working properly, the fan will engage after several minutes.

If the fan engages within 5 minutes, proceed to Test 32.

If the fan does not engage within 5 minutes, replace the freon fan pressure switch. Retest to be sure the problem has been corrected.

Test 17 Checking for an open between the solenoid and the freon fan pressure switch

Figure 324 — Freon Fan Pressure Switch

Never place hands near the fan or belts while the engine is running.

1. Turn the ignition key to the OFF position.

2. Connect a jumper between pin B of the pressure switch connector and pin B of the freon fan pressure switch connector.

3. Connect a jumper from pin A of the pressure switch connector to a good ground.

Figure 325 — Continuity between Pin B and Pin B

1. Turn the ignition key to the OFF position.

2. Disconnect the engine harness from the fan clutch solenoid connector.

Coolant temperature cannot be controlled in this mode. Monitor the coolant temperature. Do not let the engine run long enough to exceed 205°F (96°C). Allow the engine to cool down if necessary.

3. Check for continuity between pin B of the fan clutch solenoid connector and pin B of the pressure switch connector.

If there is continuity, proceed to Test 34.

If there is no continuity, the harness is open between the fan clutch solenoid connector and the freon fan pressure switch connector. Locate and repair the open. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS ON/OFF FAN CONTROL VERBAL COMPLAINT (continued) Test 19 Checking for air supply — HORTON only 1. Crack the air supply line leading to the solenoid.

If air flows out of the supply line, proceed to Test 39.

If air does not flow out of the supply line, there is a blockage in the supply line or some other air system problem. Locate and repair the problem.

Retest to be sure the problem has been corrected.

If the fan cycles quickly, erratically, or is ON for long periods of time while the coolant temperature is below 170°F (77°C), and the connections to the harness, switch and ground are good, there is not a problem with the electrical and pneumatic portions of the fan control system. There may be a problem with the level of refrigerant charge in the system, a plugged condenser core, or elsewhere. Locate and repair the problem. Retest to be sure the problem has been corrected.

Test 34 Checking for a short to ground between the solenoid and the freon fan pressure switch

Test 22 Checking for correct plumbing of the solenoid 1. Tighten the air supply line.

2. Remove the vent cap or vent line from the solenoid.

If air flows out of the vent, the solenoid is plumbed incorrectly. Reverse the vent and air supply lines on the solenoid. Retest the fan drive.

If air does not flow out of the vent, the solenoid is defective. Repair or replace the solenoid. Retest the fan drive.

Test 32 Testing for proper freon charge

If the fan cycles on a regular basis, proceed to Test 64.

If the fan turns ON immediately after the engine is started and remains ON, never turning OFF, verify proper jumper connections to the harness, switch and ground. If the fan still does not turn OFF, visually inspect the pressure switch connector for dirt, wear, and evidence of an open connection. If there is no damage, replace the switch and retest the fan drive.

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Figure 326 — Continuity between Pin B and Ground

1. Check for continuity from pin B of the fan clutch solenoid engine connector to a good ground.

If there is continuity, the harness is shorted to ground between the fan clutch solenoid connector and the freon fan pressure switch connector. Locate and repair the short. Retest to be sure the problem has been corrected.

If there is no continuity, the fan clutch solenoid connector is open. Visually inspect the connector for dirt, wear, and open connections. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS ON/OFF FAN CONTROL VERBAL COMPLAINT (continued) Test 39 Checking for correct plumbing of the solenoid 1. Tighten the air supply line.

2. Remove the vent cap or vent line from the solenoid.

5. Connect the serial link jumper into the serial communication port.

6. Measure the voltage from J1B connector pin Y2 (the Auxiliary No. 1 output line) to a good ground.

If 12 volts are present, proceed to Test 128.

If air flows out of the vent, the solenoid is plumbed incorrectly. Reverse the vent and air supply lines on the solenoid and retest the fan drive.

If 12 volts are not present, proceed to Test 129.

If air does not flow out of the vent, the solenoid is defective. Repair or replace the solenoid and retest the fan drive.

Checking override switch operation

Test 128

Test 64 Checking for 12 volts at the V-MAC II module

Figure 328 — Voltage between Pin Y2 and Ground

If a manual override switch used, set the switch to the ON or override position.

Figure 327 — Voltage from Pin Y2 to Ground

1. Turn the ignition key to the OFF position.

If a manual override switch is not used, proceed to Test 256.

1. Measure the voltage from J1B connector pin Y2 (the Auxiliary No. 1 output line) to a good ground.

2. Reconnect the harness to the freon fan pressure switch.

If 12 volts are present, proceed to Test 257.

3. Disconnect the J1B connector from the V-MAC II module.

If 12 volts are not present, turn the override switch to the OFF position, proceed to Test 256.

4. If there is an override switch on the dash, turn it to the OFF or normal operation position.

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SYMPTOM RELATED DIAGNOSTICS ON/OFF FAN CONTROL VERBAL COMPLAINT (continued) Test 129

Test 256

Checking for a short to ground between the pressure switch and the module

Checking for a pin-to-pin short

Figure 329 — Continuity from Pin Y2 to Ground

1. If a manual override switch is used, set the switch to the OFF or normal position.

Figure 330 — Continuity between Pin Y2 and All Other Pins

1. Disconnect the serial link jumper.

2. Disconnect the serial link jumper.

2. Disconnect the engine harness from the fan clutch solenoid connector.

3. Disconnect the harness at the freon fan pressure switch.

3. Disconnect the J1A and J2 connectors from the V-MAC II module.

4. Check for continuity from J1B connector pin Y2 (the Auxiliary No. 1 output line) to a good ground.

4. Check for continuity between J1B connector pin Y2 (the Auxiliary No. 1 output line) and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

If there is continuity, there is a short to ground between the freon fan pressure switch, override switch (if used) and the V-MAC II module. Locate and repair the short to ground. Retest to be sure the problem has been corrected.

If there is no continuity, there is an open at the freon fan pressure switch connector, or between the freon fan pressure switch, override switch (if used) and the V-MAC II module. Locate and repair the open. Retest to be sure the problem has been corrected.

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If there is continuity with another pin, locate and repair the short to pin Y2. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 512.

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SYMPTOM RELATED DIAGNOSTICS ON/OFF FAN CONTROL VERBAL COMPLAINT (continued) Test 257

5. Turn the ignition key to the ON position.

Checking for a short to voltage

6. Turn the override switch to the OFF or normal position.

With the coolant temperature below 170°F (77°C) if the fan turns freely, proceed to Test 1024.

If the fan does not turn freely, visually inspect the J1B connector for dirt, corrosion, and evidence of an open. If there is no evidence of an open, replace the V-MAC II module. Retest to be sure the problem has been corrected.

Figure 331 — Voltage from Pin Y2 to Ground

1. Disconnect the serial link jumper.

2. Remove the override switch from the dash.

3. Disconnect the cab harness from the switch.

4. Connect the serial link jumper into the serial communication port.

5. Measure the voltage from J1B module connector pin Y2 (the Auxiliary No. 1 output line) to a good ground.

If 12 volts are present, there is a short to voltage between the override switch connector and the J1B module connector. Locate and repair the short. Retest to be sure the problem has been corrected.

Test 1024 Testing the system when hot 1. View the Customer Data Table in V-MAC II to determine the temperature at which the fan should engage.

2. Start the engine. Turn off the air conditioning. Allow the coolant temperature to increase.

3. Monitor the engine temperature with a diagnostic tool and with the dashboard temperature gauge. If the two temperatures do not agree, there may be a problem with the gauge which makes it appear that the fan is not turning on at the proper time.

If 12 volts are not present, replace the override switch and retest the fan drive.

4. Once the engine temperature exceeds the customer’s setting, the fan should turn ON.

Test 512

5. After the fan has turned ON, the fan should turn OFF approximately 7°F (4°C) below the engagement temperature.

Testing the system when cold 1. Reconnect the J1A, J1B and J2 connectors.

2. Reconnect the engine harness to the fan clutch solenoid connector.

3. Start the engine. Turn off the air conditioning. Allow the air pressure to build up to at least 90 psi.

If the fan engages and disengages at the proper temperatures, there is not a problem with the electrical and pneumatic portions of the fan control system.

If the fan does not engage and disengage at the proper temperatures and the engine temperatures agree, replace the V-MAC II module. Retest to be sure the problem has been corrected.

4. When operating conditions are such that the fan is OFF or should be OFF, stop the engine.

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SYMPTOM RELATED DIAGNOSTICS SWITCH CIRCUIT DIAGNOSTICS Introduction This section of the manual covers the general diagnostic procedures for V-MAC II switches and outlines steps to take if any of the switch inputs have failed. Procedures for specific switches may be found in the Diagnostic Codes and Tests section or earlier in this section. Follow the instructions here for general diagnostic and repair procedures.

Figure 332 — Speed Control Switch J2 Module Pin Numbers

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SYMPTOM RELATED DIAGNOSTICS SWITCH CIRCUIT FAILURE

Figure 333 — Diagnostic Procedure Flowchart

This section outlines the procedure for determining the source of the problem.

Test 2 Checking module connector

Test 1

1. Turn the ignition key to the OFF position.

Checking switch operation

2. Disconnect the appropriate V-MAC II connector.

1. Using a diagnostic tool (Pro-Link or PC), check the status of the switch as you turn the switch ON and OFF with the ignition key to the ON position.

If the switch status displayed on the diagnostic tool toggles properly, but there was a complaint that the switch was not working properly, check for good connections at the switch. In the case of the clutch switch, check for proper switch adjustment. Retest to be sure the problem has been corrected.

3. Check both sides of the V-MAC II connector for problems such as bent, loose, missing or corroded pins.

If the pins are in good condition, proceed to Test 4.

If the pins are damaged, replace the connector pins or the V-MAC II module. Retest to be sure the problem has been corrected.

If the switch status displayed on the diagnostic tool does not toggle properly, always remaining ON or OFF, proceed to Test 2.

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SYMPTOM RELATED DIAGNOSTICS SWITCH CIRCUIT FAILURE (continued) Test 4

Test 17

Checking for stray voltage at the module

Checking for voltage to the switch

1. Turn the ignition key to the ON position.

1. Turn the ignition key to the OFF position.

2. With the switch OFF, measure the voltage from the pin at the V-MAC II module connector to a good ground.

2. Disconnect the wire leading from the switch terminal to the V-MAC II module at the switch terminal.

If the voltage is greater than 0.5 volts, proceed to Test 9.

If the voltage is less than 0.5 volts, proceed to Test 8.

3. Turn the ignition key to the ON position.

4. Measure the voltage at the switch voltage supply terminal to a good ground.

If 12 volts are present, proceed to Test 34.

Test 8 Checking switch voltage at the module 1. With the switch ON, measure the voltage from the pin at the V-MAC II module connector to a good ground.

If the voltage is greater than 10 volts, replace the V-MAC II module. Retest to be sure the problem has been corrected.

If 12 volts are not present, there is a loss of power to the switch. Locate and repair the problem.

Retest to be sure the problem has been corrected.

Test 19 Checking for a short in the harness 1. Turn the ignition key to the OFF position.

If the voltage is less than 10 volts, proceed to Test 17.

2. Disconnect the remaining V-MAC II module connectors.

Test 9

3. Check for continuity between the switch signal pin and each of the other pins (one at a time) on the J1A, J1B and J2 connectors.

Checking for a short to voltage in the harness 1. Turn the ignition key to the OFF position.

2. Disconnect the wire supplying 12 volts to the switch at the switch terminal.

3. Turn the ignition key to the ON position.

4. Measure the voltage from the V-MAC II module connector pin to a good ground.

If 12 volts are present, proceed to Test 19.

If 12 volts are not present, examine the switch for bent or damaged pins that would cause a short to voltage. Repair the pins or replace the switch.

Retest to be sure the problem has been corrected.

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If there is continuity with another pin, locate and repair the short in the harness. Retest to be sure the problem has been corrected.

If there is no continuity, there is a short to voltage somewhere else in the cab or dashboard, between the switch and the V-MAC II module.

Locate and repair the short to voltage. Retest to be sure the problem has been corrected.

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SYMPTOM RELATED DIAGNOSTICS SWITCH CIRCUIT FAILURE (continued) Test 34

Test 138

Checking for proper switch operation

Checking for a short to ground in the switch

1. Turn the ignition key to the OFF position.

2. Turn the switch ON. 3. Check for continuity across the two leads of the switch.

If there is continuity, proceed to Test 69.

If there is no continuity, replace the switch. Retest to be sure the problem has been corrected.

1. With the ignition key in the OFF position, check for continuity from either pin on the switch to a good ground. Turn the switch ON and OFF.

If at any time there is continuity between the switch and ground, replace the switch. Retest to be sure the problem has been corrected.

If there is no continuity with ground, there is a break in the wire which supplies the switch signal to V-MAC II. Repair or replace the wire. Retest to be sure the problem has been corrected.

Test 69 Checking for a short to ground 1. Disconnect the remaining V-MAC II module connectors.

2. Check for continuity between the switch signal pin and each of the other pins (one at a time) on the J1A, J1B and J2 connectors, and also a good ground.

If there is continuity with another pin or ground, locate and repair the short in the harness. Retest to be sure the problem has been corrected.

If there is no continuity, proceed to Test 138.

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SYMPTOM RELATED DIAGNOSTICS SYMPTOM RELATED TROUBLESHOOTING CHART Problem

Additional Symptoms

Possible Failure

Service Hints

Unable to set cruise/speed control with lights ON (turn signals, headlights).

Speed control can be reset once lights are turned ON, but not turn signals.

GENERAL: Continuity between J2 connector pins B2 or B3 (service and parking brake lines) and the lighting circuit.

First watch tractor tail/stop lamps. Turn on the lights in question and see if the lamps turn ON. If they do not turn ON, or turn ON dimly, repair the lamps.

Front directional lamp ground.

Tractor or trailer ground connections.

Faulty directional switch operation.

Tractor or trailer rear directional lamp ground.

Able to set cruise/speed control but it disengages intermittently.

Cruise automatically resumes itself.

Clutch switch adjustment.

Intermittent short (closed contact) in clutch switch.

Intermittent short to voltage after clutch switch engaged line (J2-C1).

Must press RESUME switch to reactivate cruise, no faults.

Faulty service brake switch Faulty park brake switch.

Intermittent short to voltage after brake switch engaged line (J2-B2 or B3).

Fault 7-1 (Service Brake) becomes active. Must press service brake and then RESUME to re-engage cruise.

Speedometer erratic.

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Open, short to ground or short to voltage on MPH (+) and MPH (−) lines (J1A-H3 or G3).

Misadjusted MPH sensor.

If the lamps work properly: Monitor the service and parking brake switch status on the PC or Pro-Link. Watch the status as you turn the various lamps ON and OFF. The status should not change.

Check clutch switch adjustment.

If adjustment is OK: Disconnect wire J2-C1 from switch leading to the module.

If the problem continues, the wire is shorted to voltage. If the problem is fixed, the clutch switch is defective.

Monitor the service and parking brake switch status on the PC or Pro-Link. Watch the status while driving in cruise.

Alternate: set up the customer definable data log to record service brake and park brake application while in cruise mode. This may be more effective if the problem occurs infrequently. The driver must be instructed to NOT use the service brake while in cruise but to disengage with the ON/OFF switch.

If the driver reports that cruise dropped out by itself (without application of the service brake) there is nothing wrong with the service brake, despite the fault. Shorts and opens on the MPH signal will appear as a sudden deceleration, causing cruise to disengage and the fault to be logged.

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SYMPTOM RELATED DIAGNOSTICS SYMPTOM RELATED TROUBLESHOOTING CHART (continued) Problem

Additional Symptoms

Possible Failure

Service Hints

Poor performance: Continuous

N/A

Verify adequate fuel and air supply.

Check filters, hoses, charge air cooler, etc.

Reduced engine speed or reduced high idle speed.

Customer’s high idle setting is lower than the driver is used to.

Determine high idle, road speed limit and lower gear road speed limits using the PC or Pro-Link. If these are the cause of the complaint, educate the driver to the set up that his fleet has specified.

Lower gear road speed limit or road speed limit is lower than the driver is used to.

Reduced high idle.

Throttle unresponsive around low idle with light loads.

May not be able to achieve 100% throttle on the PC or Pro-Link display.

Throttle pedal reference line (J1B-L2) should be 5 volts.

Examine the % throttle with the PC or Pro-Link.

Intermittent problems: Poor connection at the module or pedal.

Faulty pedal.

Poor module ground connection or throttle ground line (J1B-L2).

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SYMPTOM RELATED DIAGNOSTICS SYMPTOM RELATED TROUBLESHOOTING CHART (continued) Problem

Additional Symptoms

Possible Failure

Service Hints

Poor performance: Engine stumbles then regains power while driving.

Runs rough under throttle pedal control.

Intermittent problems: Throttle pedal reference line (J1B-L2) intermittent open or short to voltage.

Examine the % throttle pedal with the PC or Pro-Link.

Does not occur in cruise or speed control unless the throttle pedal is applied.

Engine brake activates when the engine stumbles (if equipped and turned ON).

Throttle pedal signal line (J1B-L1) intermittent open, short to voltage or short to ground.

Use enhanced diagnostics mode of the PC or Pro-Link if fault codes are not present.

Throttle pedal ground line (J1B-L3) intermittent open or short to voltage.

Intermittent bad module ground.

Faulty throttle pedal.

Runs rough all of the time, under throttle pedal control, cruise control and speed control.

Loose injection pump connector.

When out of gear, the engine speed jumps up or down.

Intermittent problems: Rack actuator (+) line (J1AH1) is open, shorted to voltage or shorted to ground.

Engine brake activates when the engine stumbles (if equipped and turned ON).

Rack position (+) line (J1AK1 or K2) is open, shorted to ground or shorted to voltage.

Tachometer needle agrees fairly well with engine speed.

Rack position (+) line (J1AJ3) is open or shorted to voltage.

Ensure that the injection pump connector ring is locked.

If the problem only occurs when the engine is hot, pour 2–3 gallons of water on the injection pump cover when the engine stumbles. If the engine runs smoothly for a period of time, the problem may be a bad connection inside the injection pump.

Send the pump to a certified pump repair shop for repair.

Check the inactive fault table for rack actuator and rack position sensor faults.

Rack actuator (+) lines (J1AB1 and B2) and rack actuator (−) lines (J1A-A2 and B3) have splices in the harness near the module. If these splices should break, there may be an intermittent open in the lines.

Similar to description above, except that the tachometer needle jumps wildly when the engine stumbles, even when the truck is in gear and the engine speed is steady.

Injection timing is erratic when the engine stumbles.

Similar to the description above, with the tachometer needle following the engine speed.

Accessory relay is sometimes heard when engine stumbles.

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Intermittent problems: RPM/TDC (+) line (J1A-H1) is open, shorted to voltage or shorted to ground.

RPM/TDC (−) line (J1A-H2) is open or shorted to voltage.

Misadjusted RPM/TDC sensor.

Faulty accessory relay.

Faulty key switch.

Disconnect the RPM/TDC sensor and run the engine.

The stumble should disappear if this is the problem.

Use the enhanced diagnostics mode of the PC or Pro-Link if fault codes are not present to find the source of the problem.

Use the standard log from the INFOMAX PC program to count key cycles while the problem occurs.

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SYMPTOM RELATED DIAGNOSTICS SYMPTOM RELATED TROUBLESHOOTING CHART (continued) Problem

Additional Symptoms

Poor performance: Engine speed rolls, particularly at low idle.

Increased low idle speed: Continuous.

Cannot reach 0% throttle (this is not always evident with this failure.

Possible Failure

Service Hints

Possible misadjusted injection pump control rod.

Refer to the instructions for diagnostic blink codes 5-4 in this manual for proper adjustment procedures.

Broken throttle pedal springs.

High throttle pedal reference voltage in excess of 5.25 volts (J1B-L2).

Continuity between pin J1B-L1 and other wires.

Poor module ground.

Engine will not start.

No fuel or fuel pressure to injection pump.

No power to the V-MAC II module.

If a new pump has been installed, make sure the pump is primed. Push on the hand primer until resistance is felt.

Low battery voltage.

Loose injection pump connector.

Misadjusted RPM/TDC sensor AND starter input (+) line (J2-A3) is open.

Use the standard log from the INFOMAX PC program to count starter engagements, or use the switch status screen on the PC or Pro-Link to monitor the starter (Auxiliary No. 3 switch).

Apply 100% throttle when cranking. Even if the sensor is misadjusted and the starter input is broken, the engine should engage.

Co-Pilot requests a code, or some other alarm is ON.

Engine shuts down, accessories turn OFF with the key in the ON position.

Module is in a theft deterrence or forced shutdown mode.

Check on the theft deterrence or forced shutdown status with the PC or Pro-Link, or check with the customer.

Idle shutdown.

Verify that the engine has not shut down due to an engine protection shut down (low oil pressure, high coolant temperature, low coolant level).

Engine protection shutdown.

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NOTES

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REPAIR AND ADJUSTMENT PROCEDURES

REPAIR AND ADJUSTMENT PROCEDURES

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REPAIR AND ADJUSTMENT PROCEDURES CONNECTOR REPAIR Deutsch Connectors The 31 or 23-pin bulkhead connector and the serial communication port connector are Deutsch connectors. To remove and replace terminals, follow the instructions listed in this section.

CONTACT INSERTION

Figure 334 — Contact Insertion

1. Grasp the contact approximately 1 inch (25.4 mm) behind the contact crimp barrel.

2. Hold the connector with the rear grommet facing you.

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3. Push the contact straight into the connector grommet until a positive stop is felt. A slight tug will confirm that it is properly locked in place.

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REPAIR AND ADJUSTMENT PROCEDURES CONTACT REMOVAL

Figure 335 — Contact Removal

1. With the rear insert toward you, snap the appropriate-size extractor tool over the wire of the contact to be removed.

CONTACT REPLACEMENT

2. Slide the tool along the wire into the insert cavity until it engages the contact and resistance is felt.

Use only the appropriate size Deutsch plastic tool. DO NOT use any other kind of tool.

Do not twist or insert the tool at an angle.

3. Pull the contact-wire assembly out of the connector.

Figure 336 — Deutsch Removal Tools

To replace a contact on a wire, use the Deutsch hand crimp tool, part No. HDT-48-00.

1. Strip approximately 1/4 inch of insulation from the wire.

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REPAIR AND ADJUSTMENT PROCEDURES 2. Remove the lock clip, raise the wire gauge selector and rotate the knob to the number matching the gauge wire you are using.

Then lower selector and insert lock clip.

Figure 339 — Adjusting the Crimp Tool

Figure 337 — Hand Crimp Tool

3. Position the contact so that the crimp barrel is 1/32 inch above the 4 intenders. It may be necessary to adjust the hand crimp tool in order to position the crimp barrel correctly.

5. Place the stripped end of the wire in the crimp barrel and fully depress the tool handles.

6. Release the handles and remove the crimped terminal.

Figure 340 — Crimping the Connector Figure 338 — Correct Contact Positioning

4. Loosen the adjustment lock and turn the contact depth adjustment to obtain 1/32 inch. Then tighten the adjustment lock.

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REPAIR AND ADJUSTMENT PROCEDURES 7. Inspect the terminal for proper crimping: r All strands should be in the crimp barrel. r The wire should be visible in the inspection hole.

TERMINAL REMOVAL To remove the terminals from these connectors, use the following procedure: 1. Grasp the connector body firmly and pull the terminal toward the rear of the connector (as far as possible).

2. Locate the terminal lock tab in the connector.

3. Insert tool No. J 35689-A straight into the slot at the front (mating end) of the connector to release the locking tab for the terminal to be removed (see illustration).

4. After releasing the tab, push the wire from the rear through the front of the connector.

TERMINAL INSTALLATION After repairing or replacing the terminal, reinstall as follows:

Figure 341 — Inspecting for Proper Crimping

V-MAC II Module, Engine Oil Pressure, Intake Manifold Temperature, and Coolant Temperature Sensors and Connectors

1. Pull the wire from the rear until the terminal slides into the connector body and locks in place.

2. Gently push the wire toward the front of the connector to be sure the terminal is locked in place.

Figure 342 — Releasing Lock Tab Body

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REPAIR AND ADJUSTMENT PROCEDURES MPH, RPM/TDC, Throttle Position, TEM Sensors and Connectors and Bulkhead Connector TERMINAL REMOVAL To remove the terminals from these two-part connectors, use the following procedure:

Removal is the same for both halves of the connector.

1. Grasp the connector body firmly and push the terminal as far forward in the connector as possible.

TERMINAL INSTALLATION After repairing or replacing the terminal, reinstall as follows: 1. Push the terminal into the connector body from the rear until it locks in place.

2. Gently pull on the wire to ensure that the terminal is locked in the connector.

On some connectors, there is a secondary lock which must be opened before the terminals can be removed.

2. Locate the terminal lock tab in the connector.

3. Insert tool No. J 33095 straight into the slot at the front (mating end) of the connector to release the locking tab for the terminal to be removed (see illustration).

Figure 344 — Open Secondary Lock Before Removing Terminals

Figure 343 — Removing the Terminal

4. Gently pull the wire from the rear of the connector and pull the terminal free.

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REPAIR AND ADJUSTMENT PROCEDURES TERMINAL REPLACEMENT To replace a terminal, use the following procedure: 1. Remove the damaged terminal from the wire, cutting as close as possible to the terminal end of the wire. If the wire has a rubber seal, remove it.

Figure 347 — Aligning Edges

Using the J 35688 Crimping Tool 1. Squeeze the handles together until the ratchet automatically opens.

2. Hold the tool so the gauge numbers are facing you.

Figure 345 — Cutting the Wire

2. Install a new rubber seal on the wire.

3. Strip approximately 1/4 inch of insulation from the wire. Be careful not to cut through any strands of the wire.

3. Insert the terminal into the terminal holder until the insulation wings are flush with the anvil on the crimp tool. Be sure that the terminal core wings and insulation wings are pointing toward the smooth concave side, opposite the anvil of the crimping jaws.

Figure 348 — inserting the Terminal Figure 346 — Removing Insulation from Wire

4. Align the edge of the rubber seal with the edge of the wire insulation.

4. Place the wire and seal into the terminal until the first rib of the seal is flush against the crimper.

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REPAIR AND ADJUSTMENT PROCEDURES 5. Cradle one handle of the crimper on a workbench so that the tool can be operated with just one hand. The anvil should be on the bottom when crimping.

Soldering Terminals

All hand-crimped terminals, except those on Deutsch connectors, must be soldered.

Figure 349 — Aligning the Seal

6. Squeeze the handles until ratchet automatically releases and the crimp is complete. Be careful to not crimp the first rib of the seal.

7. Visually inspect for a good crimp.

Figure 350 — Solder the Terminal

1. Place the tip of the soldering iron on the back of the terminal core wings.

2. Apply solder to the end of the terminal at the top of the core crimp.

3. Move the terminal core up and down on the soldering iron for a good solder flow.

Excess solder may interfere with the lock tab or mating functions.

Apply heat only until the solder flows freely. Over heating the terminal may damage the terminal or insulation.

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REPAIR AND ADJUSTMENT PROCEDURES 4. Inspect the terminal for a good solder application.

Connector bodies are keyed for proper mating of contacts. Be sure that the contacts are aligned properly.

Before inserting the contacts, carefully spread the locking tabs to ensure a good lock in the connector body.

Figure 351 — Close-Up of Soldering the Terminal

When replacing contacts, except those on a Deutsch connector, they must all be soldered after crimping.

After making any repairs to connectors, make sure that all rubber seals are properly positioned on the connectors before reconnecting them.

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REPAIR AND ADJUSTMENT PROCEDURES CLUTCH SWITCH ADJUSTMENT For proper operation of the engine brake and speed control functions, the clutch switch must be adjusted and working properly. The clutch switch is located under the dash, near the top of the clutch pedal assembly. This switch is a “normally open” switch. However, when used with a V-MAC II system, it is set to be closed during normal operation and opens only when the clutch pedal is depressed.

Two mounting screws hold this switch in place.

Loosening the two screws makes it possible to move the switch slightly, to permit adjustment.

Make sure that the clutch switch is closed when the clutch pedal is in the fully released (not depressed) position, and open when the clutch pedal is depressed. Be sure to adjust the switch to allow approximately 1/2 inch of clutch free play travel before the switch opens.

RESETTING LOW IDLE SPEED This section explains the procedure for resetting low idle speed using the speed control switches.

The V-MAC II system allows the low idle to be set within the range of 500 to 750 rpm. This range of flexibility allows the operator to set the low idle to the smoothest possible engine speed for the vehicle.

Resetting the low idle speed involves two steps: 1. Place V-MAC II in the “low idle adjust” mode (so that V-MAC can accept the new low idle speed).

2. Set the new idle speed.

Completing the first step in the process requires the following: r

SENSOR ADJUSTMENT

The V-MAC II module must have the Low Idle Adjust option enabled in using Customer Data Programming software.

RPM/TDC Sensor 1. Turn the sensor in by hand until it bottoms against the flywheel.

2. Back out exactly 1 turn.

3. Torque the jam nut to 15 lb-ft (20 N•m).

MPH Sensor 1. Turn the sensor in by hand until it bottoms against the speedometer tone wheel.

The PTO minimum engine speed in Customer Data should be set at 475 rpm. Otherwise, the low idle speed can be adjusted only by using a diagnostic tool (Pro-Link or PC). r

There must be no active faults in the system.

r

The vehicle must be stationary.

r

The parking brake must be applied.

r

The throttle pedal must be at the idle position (not depressed).

r

The speed control ON/OFF switch must be turned ON and OFF 3 times within 2 seconds. At this point, the idle speed will drop to 500 rpm — V-MAC II is now ready to accept a new speed. Be sure to leave the switch in the ON position.

2. Back out exactly 1 turn.

3. Torque the jam nut to 15 lb-ft (20 N•m).

TEM Sensor 1. Coat the sensor thread with Silastic.

2. Turn in by hand until it bottoms in the housing.

3. Torque the jam nut to 22 lb-ft (30 N•m).

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REPAIR AND ADJUSTMENT PROCEDURES To complete the second step (resetting the low idle speed): 1. Depress and hold the accelerator pedal until the desired engine speed is achieved.

2. Press and release the SET switch.

3. While still at the desired engine speed, depress the clutch pedal and V-MAC II will “lock in” the desired speed as the new low idle speed.

It is recommended that the low idle speed be set to a speed greater than 500 rpm to allow for detection of a drop when resetting the idle.

Figure 352 — Speed Control Switches

If the idle speed does not drop to 500 rpm after meeting the requirements listed, there may be other possible problems which will not allow the idle to be reset. Refer to the Switch Circuit Diagnostics section for switch troubleshooting procedures.

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NOTES

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SPECIFICATIONS

SPECIFICATIONS

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SPECIFICATIONS V-MAC I AND II E7 ENGINE PARAMETERS (1995 AND LATER)

Figure 353 — E7 Engine Parameters

Full load fuel rate and command timing are measured after at least 20 seconds of steady state (RPM and load) operation.

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SPECIAL TOOLS

SPECIAL TOOLS

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SPECIAL TOOLS TOOL LIST This section lists the tools required to properly service the V-MAC II system.

Tool Number

Description

J 37077 (Kent-Moore)

Timing indicator light (P7100 pump)

J 38740 (Kent-Moore)

Electronic injection pump hub barring tool

J 38351(B) (Kent-Moore)

SAE/ATA J 1708 serial link adapter

J 38581 (Kent-Moore)

V-MAC electronic connector test adaptor kit

J 38582 (Kent-Moore)

V-MAC terminal crimper/removal tool kit

J 38675B (Kent-Moore)

Pro-Link 9000 hand-held diagnostic analyzer with V-MAC II diagnostic cartridge

J 38748 (Kent-Moore)

Electronic injection pump test harness assembly

AN8508-22A (Snap-On)

Flare nut wrench (1-3/8 inch, 12 point, or equivalent)

J 38500-63 (Kent-Moore)

Serial link jumper (Deutsch-to-Deutsch) Any digital multimeter accurate to 2% with a minimum input impedance of 10 megohm, and a 10 AMP range.

Any 100% IBM-compatible computer Any Hayes-compatible modem.

The following tools are part of the J 38582 V-MAC terminal crimper/removal tool kit. These tools are available individually and are listed here for reference.

J 33095

MPH, RPM/TDC, BULKHEAD, TPS and TEM connector terminal removal tool

J 35688

Terminal crimping tool

J 35689-A

Engine oil pressure sensor, intake manifold temperature sensor, coolant temperature sensor connector terminal removal tool

J 386761

Fuel pump actuator connector terminal removal tool (Bosch 7 pin)

HDT-48-00

Deutsch terminal crimping tool

0411-204-1605

Deutsch 18/16-gauge (0.8/1.0 metric) wire removal tool (blue)

0411-291-1405

Deutsch 14-gauge (2.0 metric) wire removal tool (green)

114010

Deutsch 12-gauge (3.0 metric) wire removal tool (yellow)

Page 234

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SAE MESSAGE DESCRIPTIONS

SAE MESSAGE DESCRIPTIONS

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SAE MESSAGE DESCRIPTIONS COMMUNICATION STANDARDS V-MAC II communicates with other devices, including diagnostic tools, in compliance with SAE J 1587 and J 1708 Communication Standards. These standards define the method by which various electronic devices can communicate with one another.

When the truck leaves the factory, V-MAC II is usually the only module using the serial communication line. In some cases a truck may

also leave with an ABS/ATC or an automatic transmission controller. However, many other devices can be connected to the serial communication line in the aftermarket. Some diagnostic tools will not only display the messages sent out by V-MAC II, but by these other devices as well.

The following table is provided for your convenience. It lists message types that are most likely to be available on the serial line if aftermarket devices are installed. For a complete list, contact the Society of Automotive Engineers.

Message Identifier (MID)

Description

128

Engine controller (used with original V-MAC)

130

Transmission

136

Brakes — Anti-lock/Traction Control

137–139

Brakes — Anti-lock, Trailer 1, 2, 3

140

Instrument Cluster

141

Trip Recorder

142

Vehicle Management System (V-MAC and V-MAC II MID)

143

Fuel System

162

Vehicle Navigation

163

Vehicle Security

165

Communication Unit — Ground

171

Driver Information System

178

Vehicle Sensors to Data Converter

181

Communication Unit — Satellite

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SAE MESSAGE DESCRIPTIONS Parameter Identifier (PID)

Description

65

Service Brake Switch

70

Parking Brake Switch

83

Road Speed Limit Status

84

Road Speed

85

Speed Control Status

91

Percent Engine Load

100

Engine Oil Pressure

102

Boost Pressure

105

Intake Manifold Temperature

106

Air Inlet Pressure

108

Barometric Pressure

110

Engine Coolant Temperature

111

Coolant Level

113

Governor Droop

158

Battery Voltage

166

Engine Rated Power

175

Engine Oil Temperature

182

Trip Fuel

183

Fuel Rate

184

Instantaneous MPG

185

Average MPG

189

Engine Rated Speed

190

Engine Speed

234

Software Version No.

235

Total Idle Hours

236

Total Idle Fuel Used

244

Trip Distance

245

Total Vehicle Distance

246

Total Vehicle Hours

247

Total Engine Hours

248

Total PTO Hours

249

Total Engine Revolutions

250

Total Fuel Used

254

Proprietary Message

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SAE MESSAGE DESCRIPTIONS Subsystem Identifiers (SID) Common to all MIDs

Description

242

Cruise Control Resume Switch

243

Cruise Control Set Switch

244

Cruise Control Enable Switch

245

Clutch Pedal Switch

248

Proprietary Data Link

250

SAE J 1708 (J 1487) Data Link

Subsystem Identifiers (SID) for MID 128, 143

Description

20

Timing Actuator

21

Engine Position Sensor

22

Timing Sensor

23

Rack Actuator

24

Rack Position Sensor

29

External Fuel Command Input

Subsystem Identifiers (SID) for MID 142

Description

1

Timing Sensor

2

Timing Actuator

3

Rack Position Sensor

4

Rack Actuator

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SAE MESSAGE DESCRIPTIONS Subsystem Identifiers (SID) for MID 130

Description

1–6

C1–C6 Solenoid Valves

7

Lockup Solenoid Valve

8

Forward Solenoid Valve

9

Low Signal Solenoid Valve

10

Retarder Enable Solenoid Valve

11

Retarder Modulation Solenoid Valve

12

Retarder Response Solenoid Valve

13

Differential Lockout Solenoid Valve

14

Engine/Transmission Match

15

Retarder Modulation Request Sensor

16

Neutral Start Output

17

Turbine Speed Sensor

18

Primary Shift Selector

19

Secondary Shift Selector

20

Special Function Inputs

21–26

C1–C6 Clutch Pressure Indicators

27

Lockup Clutch Pressure Indicator

28

Forward Range Pressure Indicator

29

Neutral Range Pressure Indicator

30

Reverse Range Pressure Indicator

31

Retarder Response System Pressure Indicator

32

Differential Lock Clutch Pressure Indicator

33

Multiple Pressure Indicators

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SAE MESSAGE DESCRIPTIONS Subsystem Identifiers (SID) for MID 136–139

Description

1

Wheel Sensor ABS Axle 1 Left

2

Wheel Sensor ABS Axle 1 Right

3

Wheel Sensor ABS Axle 2 Left

4

Wheel Sensor ABS Axle 2 Right

5

Wheel Sensor ABS Axle 3 Left

6

Wheel Sensor ABS Axle 3 Right

7

Pressure Modulation Valve ABS Axle 1 Left

8

Pressure Modulation Valve ABS Axle 1 Right

9

Pressure Modulation Valve ABS Axle 2 Left

10

Pressure Modulation Valve ABS Axle 2 Right

11

Pressure Modulation Valve ABS Axle 3 Left

12

Pressure Modulation Valve ABS Axle 3 Right

13

Retarder Control Relay

14

Relay Diagonal 1

15

Relay Diagonal 2

16

Mode Switch — ABS

17

Mode Switch — Traction Control

18

DIF 1 — Traction Control Valve

19

DIF 2 — Traction Control Valve

22

Speed Signal Input

23

Warning Light Bulb

24

Traction Control Light Bulb

25

Wheel Sensor, ABS Axle 1 Average

26

Wheel Sensor, ABS Axle 2 Average

27

Wheel Sensor, ABS Axle 3 Average

28

Pressure Modulator, Drive Axle Relay Valve

29

Pressure Transducer, Drive Axle Relay Valve

30

Master Control Relay

Subsystem Identifiers (SID) for MID 162

Description

1

Dead Reckoning Unit

2

Loran Receiver

3

Global Positioning System (GPS)

4

Integrated Navigation Unit

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SAE MESSAGE DESCRIPTIONS Failure Mode Identifiers

Description

0

Data valid but above normal operating range

1

Data valid but below normal operating range

2

Data erratic, intermittent or incorrect

3

Voltage above normal or shorted high

4

Voltage below normal or shorted low

5

Current below normal or open circuit

6

Current above normal or grounded circuit

7

Mechanical system not responding properly

8

Abnormal frequency, pulse width, or period

9

Abnormal update rate

10

Abnormal rate of change

11

Failure mode not identifiable

12

Bad intelligent device or component

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NOTES

Page 242

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INDEX

INDEX

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INDEX A ACCESSORY RELAY CONTROL . . . . . . . . . 15 B BATTERY VOLTAGE TESTS. . . . . . . . . . . . .151 BLINK CODE DIAGNOSTICS . . . . . . . . . . . . .29 BUFFERED MPH (SPEEDOMETER SIGNAL) . . . . . . . . . . . . . . . . . . . . . . . . . .176 BUFFERED RPM (TACH DRIVE OUTPUT) .198 C CAB AND DASHBOARD SWITCHES . . . . . . . .5 CLUTCH SWITCH ADJUSTMENT. . . . . . . . .228 COMMUNICATION STANDARDS . . . . . . . . .236 COMPONENT DESCRIPTIONS . . . . . . . . . . . .3 CONNECTOR REPAIR . . . . . . . . . . . . . . . . .220 COOLANT LEVEL SENSOR . . . . . . . . . . . . . . .5 COOLANT LEVEL SENSOR TESTS . . . . . . . .42 COOLANT TEMPERATURE SENSOR . . . . . . .5 COOLANT TEMPERATURE SENSOR TESTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51 D DESCRIPTION AND OPERATION . . . . . . . . . .1 DETERMINING DIAGNOSTIC BLINK CODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 DETERMINING THAT A FAULT EXISTS. . . . .25 DEUTSCH CONNECTORS . . . . . . . . . . . . . .220 DIAGNOSTIC BLINK CODES . . . . . . . . . . . . .22 DIAGNOSTIC BLINK CODE 1-1 OR 1-2 . . . . .30 DIAGNOSTIC BLINK CODE IDENTIFICATION CHART . . . . . . . . . . . . . .23 DIAGNOSTIC BLINK CODE 1-7 . . . . . . . . . . .42 DIAGNOSTIC BLINK CODE 1-8 . . . . . . . . . . .47 DIAGNOSTIC BLINK CODE 2-1 OR 2-2 . . . . .51 DIAGNOSTIC BLINK CODE 2-3 OR 2-4 . . . . .62 DIAGNOSTIC BLINK CODE 3-2 . . . . . . . . . . .74 DIAGNOSTIC BLINK CODE 3-4 . . . . . . . . . . .79 DIAGNOSTIC BLINK CODE 3-5, BASIC . . . . .84 DIAGNOSTIC BLINK CODE 3-5, ELECTRICAL . . . . . . . . . . . . . . . . . . . . . . . .90 DIAGNOSTIC BLINK CODE 3-5, ADVANCED . . . . . . . . . . . . . . . . . . . . . . . . .96 DIAGNOSTIC BLINK CODE 4-1, 4-2 OR 4-3 . . . . . . . . . . . . . . . . . . . . . . . . .103

Page 244

DIAGNOSTIC BLINK CODE 5-1 . . . . . . . . . . 111 DIAGNOSTIC BLINK CODE 5-2 . . . . . . . . . . 118 DIAGNOSTIC BLINK CODE 5-3 . . . . . . . . . . 124 DIAGNOSTIC BLINK CODE 5-4 . . . . . . . . . . 128 DIAGNOSTIC BLINK CODE 5-5 . . . . . . . . . . 130 DIAGNOSTIC BLINK CODE 5-6 . . . . . . . . . . 135 DIAGNOSTIC BLINK CODE 5-7 OR 5-8 . . . . 138 DIAGNOSTIC BLINK CODE 5-9 OR 5-10 . . . 144 DIAGNOSTIC BLINK CODE 6-5 . . . . . . . . . . 151 DIAGNOSTIC BLINK CODE 6-6 . . . . . . . . . . 155 DIAGNOSTIC BLINK CODE 7-1 . . . . . . . . . . 157 DIAGNOSTIC BLINK CODE 7-5 . . . . . . . . . . 162 DIAGNOSTIC BLINK CODE 7-6 . . . . . . . . . . 167 DIAGNOSTIC BLINK CODE 7-7 . . . . . . . . . . 172 DIAGNOSTIC SOFTWARE . . . . . . . . . . . . . . . 18 DIAGNOSTIC TOOLS & PROCEDURES . . . . 17 DIGITAL MULTIMETER . . . . . . . . . . . . . . . . . . 20 DRIVER ALARM OUTPUT TESTS . . . . . . . . 138 E E7 ENGINE PARAMETERS (1995 AND LATER) . . . . . . . . . . . . . . . . . . . . . . . 232 ECONOVANCE TIMING ADVANCE MECHANISM . . . . . . . . . . . . . . . . . . . . . . . . . 4 ELECTRONIC MALFUNCTION LAMP . . . . . . . 6 ELECTRONIC MALFUNCTION LAMP TESTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 ENGINE BRAKE VERBAL COMPLAINT . . . . 188 ENGINE OIL PRESSURE SENSOR . . . . . . . . . 5 ENGINE OIL PRESSURE SENSOR TESTS . . 30 ENGINE OIL PRESSURE, INTAKE MANIFOLD TEMPERATURE, AND COOLANT TEMPERATURE SENSORS AND CONNECTORS . . . . . . . . . . . . . . . . . . . . . 223 ENGINE PROTECTION SHUTDOWN. . . . . . . 15 ENGINE SHUTDOWN . . . . . . . . . . . . . . . . . . . 28 F FUEL CONTROL . . . . . . . . . . . . . . . . . . . . . . . 13 FUEL CONTROL ACTUATOR TESTS . . . . . . . . . . . . . . . . 124, 128, 130, 135 FUEL INJECTION PUMP. . . . . . . . . . . . . . . . . . 3 FUEL RACK ACTUATOR . . . . . . . . . . . . . . . . . 3 G GENERAL INFORMATION . . . . . . . . . . . . . . . . 2

8_206end.fm Page 245 Thursday, July 2, 1998 1:21 PM

INDEX I

R

IBM-COMPATIBLE PC . . . . . . . . . . . . . . . . . . .21 IDLE SHUTDOWN . . . . . . . . . . . . . . . . . . . . . .15 INCORRECT OIL PRESSURE VERSUS GAUGE . . . . . . . . . . . . . . . . . . . . . . . . . . . .186 INFORMATIONAL SWITCHES . . . . . . . . . . . . .5 INJECTION PUMP RPM (ENGINE SPEED) SENSOR. . . . . . . . . . . . . . . . . . . . . . . . . . .187 INTAKE-MANIFOLD AIR TEMPERATURE SENSOR. . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 INTAKE MANIFOLD AIR TEMPERATURE SENSOR TESTS . . . . . . . . . . . . . . . . . . . . .62 INTERMITTENT PROBLEMS. . . . . . . . . . . . .182 INTERNAL COMMUNICATIONS TESTS . . . .155 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . vii

RACK POSITION SENSOR TESTS . . . . . . . . . . . . . . . . . . . . 162, 167, 172 REPAIR AND ADJUSTMENT PROCEDURES . . . . . . . . . . . . . . . . . . . . . 219 RESETTING LOW IDLE SPEED . . . . . . . . . . 228 ROAD SPEED LIMITING . . . . . . . . . . . . . . . . . 14 RPM/TDC (ENGINE POSITION) SENSOR . . . . 4 RPM/TDC (ENGINE POSITION) SENSOR TESTS . . . . . . . . . . . . . . . . . . . . . 74 RPM/TDC SENSOR . . . . . . . . . . . . . . . . . . . . 228

J J 1708 SERIAL DATA LINK ADAPTOR . . . . . .21 J 38500-63 SERIAL LINK JUMPER . . . . . . . . .21 L LOCATING DIAGNOSTIC BLINK CODE INFORMATION. . . . . . . . . . . . . . . . . . . . . . .25 LOW COOLANT LEVEL . . . . . . . . . . . . . . . . .180 LOW OIL PRESSURE WITH DRIVER ALARM . . . . . . . . . . . . . . . . . . . . . . . . . . . .184 M MAJOR FUNCTIONS CHART . . . . . . . . . . . . .13 MPH (ROAD SPEED) SENSOR. . . . . . . . . . . . .4 MPH (ROAD SPEED) SENSOR TESTS . . . .103 MPH, RPM/TDC, THROTTLE POSITION, TEM SENSORS AND CONNECTORS AND BULKHEAD CONNECTOR . . . . . . . . . . . .224 MPH SENSOR . . . . . . . . . . . . . . . . . . . . . . . .228 O ON/OFF FAN CONTROL . . . . . . . . . . . . . . . . .15 ON/OFF FAN CONTROL VERBAL COMPLAINT . . . . . . . . . . . . . . . . . . . . . . . .201

S SAE/ATA SERIAL LINE . . . . . . . . . . . . . . . . . . 18 SAE MESSAGE DESCRIPTIONS . . . . . . . . . 235 SAFETY INFORMATION . . . . . . . . . . . . . . . . . .iii SENSOR ADJUSTMENT . . . . . . . . . . . . . . . . 228 SENSOR CONNECTORS . . . . . . . . . . . . . . . . 11 SERIAL COMMUNICATION PORT . . . . . . . . . 11 SERVICE BRAKE SWITCH TESTS. . . . . . . . 157 SERVICE HINTS . . . . . . . . . . . . . . . . . . . . . . . 26 SHUTDOWN INDICATOR LAMP AND ALARM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 SHUTDOWN OVERRIDE SWITCH . . . . . . . . . . 5 SOFTWARE FUNCTIONS . . . . . . . . . . . . . . . . 18 SOLDERING TERMINALS. . . . . . . . . . . . . . . 226 SPECIAL TOOLS . . . . . . . . . . . . . . . . . . . . . . 233 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . 231 SPEED CONTROL SWITCHES. . . . . . . . . . . . . 5 SPEED CONTROL/CRUISE CONTROL . . . . . 14 STARTER INPUT TESTS . . . . . . . . . . . . . . . . 47 SWITCH CIRCUIT DIAGNOSTICS . . . . . . . . 210 SWITCH CIRCUIT FAILURE . . . . . . . . . . . . . 211 SYMPTOM RELATED DIAGNOSTICS . . . . . 175 SYMPTOM RELATED TROUBLESHOOTING CHART . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 SYSTEM COMPONENTS . . . . . . . . . . . . . . . . 27 SYSTEM CONNECTORS . . . . . . . . . . . . . . . . . 7 SYSTEM LAMPS . . . . . . . . . . . . . . . . . . . . . . . . 6 SYSTEM SENSORS . . . . . . . . . . . . . . . . . . . . . 4

P PERFORMING DIAGNOSTIC TESTS . . . . . . .25 PRO-LINK 9000 . . . . . . . . . . . . . . . . . . . . . . . .20

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INDEX T

U

31- AND 23-PIN BULKHEAD CONNECTORS . . . . . . . . . . . . . . . . . . . . . .11 TEM SENSOR . . . . . . . . . . . . . . . . . . . . . . . .228 TERMINAL REPLACEMENT . . . . . . . . . . . . .225 TEST PROCEDURES . . . . . . . . . . . . . . . . . . .26 THROTTLE POSITION SENSOR (TPS) . . . . . .5 THROTTLE POSITION SENSOR (TPS) TESTS . . . . . . . . . . . . . . . . . . . . . . . .111, 118 TIMING ACTUATOR TESTS, ADVANCED MECHANICAL SECTION . . . . . . . . . . . . . . .96 TIMING ACTUATOR TESTS, BASIC MECHANICAL SECTION . . . . . . . . . . . . . . .84 TIMING ACTUATOR TESTS, ELECTRICAL SECTION . . . . . . . . . . . . . . . . . . . . . . . . . . .90 TIMING CONTROL. . . . . . . . . . . . . . . . . . . . . .13 TIMING EVENT MARKER (TEM). . . . . . . . . . . .4 TIMING EVENT MARKER (TEM) TESTS . . . .79 TOOL LIST . . . . . . . . . . . . . . . . . . . . . . . . . . .234 TORQUE LIMITING SWITCH. . . . . . . . . . . . . . .5 TROUBLESHOOTING PROCEDURES . . . . . .25

USING THE J 35688 CRIMPING TOOL . . . . 225

Page 246

V V-MAC I AND II E7 ENGINE PARAMETERS (1995 AND LATER) . . . . . . . . . . . . . . . . . . 232 V-MAC II MODULE . . . . . . . . . . . . . . . . . . . 3, 27 V-MAC II MODULE CONNECTORS . . . . . . . . . 7 V-MAC II MODULE, ENGINE OIL PRESSURE, INTAKE MANIFOLD TEMPERATURE, AND COOLANT TEMPERATURE SENSORS AND CONNECTORS . . . . . . . . . . . . . . . . . 223 W WIRE AND CONNECTORS. . . . . . . . . . . . . . . 27

®

V-MAC II SERVICE MANUAL PRINTED IN U.S.A. 8-206

© MACK TRUCKS, INC. 1998