99739-66100
Service Manual GP40K, GP40KL, GP45K, GP50K; DP40K, DP40KL, DP45K, DP50K Chassis & Mast GP40K GP40KL GP45K GP50K
ET29B-00011-up ET29B-50001-up ET29B-80001-up ET33A-50001-up
DP40K DP40KL DP45K DP50K
ET19C-00011-up ET19C-50001-up ET19C-80001-up ET28B-50001-up
For use with GM4.3L, S6S Engine Service Manual
FOREWORD
This service manual is a guide to servicing of CaterpillarŽ Lift Trucks. The instructions are grouped by systems to serve the convenience of your ready reference. Long productive life of your lift trucks depends to a great extent on correct servicing – the servicing consistent with what you will learn from this service manual. We hope you read the respective sections of this manual carefully and know all the components you will work on before attempting to start a test, repair or rebuild job. The descriptions, illustrations and specifications contained in this manual were of the trucks of serial numbers in effect at the time it was approved for printing. Caterpillar reserves the right to change specifications or design without notice and without incurring obligation. GP40K, GP40KL, GP45K, and GP50K are powered by GM4.3L gasoline engine. DP40K, DP40KL, DP45K, and DP50K are powered by Mitsubishi S6S diesel engine.
Safety Related Signs The following safety related signs are used in this service manual to emphasize important and critical instructions: WARNING
Indicates a specific potential hazard resulting in serious bodily injury or death.
CAUTION
Indicates a specific potential hazard resulting in bodily injury, or damage to, or destruction of, the machine.
NOTE
Indicates a condition that can cause damage to, or shorten service life of, the machine.
Pub. No. 99739-66100
HOW TO READ THIS MANUAL Disassembly diagram (example)
Each disassembly diagram is followed by Disassembly sequence and Suggestions for disassembly.
Disassembly sequence Sequence 1. Cover, Bolt, Washer (part name) 2. Output shaft (part name)
Suggestion for disassembly (1) Output shaft removal Unit: mm (in.) A
0.020 to 0.105 (0.00079 to 0.00413)
B
0.15 (0.0059)
Clearance between cylinder and piston
A: Standard value
Symbols or abbreviations OP ...................Option R1/4.................Taper pipe thread (external) 1/4 inch (formerly PT1/4) Rc1/8 ...............Taper pipe thread (internal) 1/8 inch (formerly PT1/8) G1/4A..............Straight pipe thread (external) 1/4 inch (formerly PF1/4-A) Rp1/8...............Straight pipe thread (internal) 1/8 inch (formerly PS1/8)
B: Repair or service limit
WARNING
SAFETY WARNING
WARNING
The proper and safe lubrication and maintenance for this lift truck, recommended by Caterpillar, are outlined in the OPERATION & MAINTENANCE MANUAL for these trucks.
Do not operate this truck unless you have read and understand the instructions in the OPERATION & MAINTENANCE MANUAL. Improper truck operation is dangerous and could result in injury or death.
Improper performance of lubrication or maintenance procedures is dangerous and could result in injury or death. Read and understand the OPERATION & MAINTENANCE MANUAL before performing any lubrication or maintenance.
4. Lower the forks or other implements to the ground before performing any work on the truck. If this cannot be done, make sure the forks or other implements are blocked correctly to prevent them from dropping unexpectedly.
The serviceman or mechanic may be unfamiliar with many of the systems on this truck. This makes it important to use caution when performing service work. A knowledge of the system and/or components is important before the removal or disassembly of any component.
5. Use steps and grab handles (if applicable) when mounting or dismounting a truck. Clean any mud or debris from steps, walkways or work platforms before using. Always face truck when using steps, ladders and walkways. When it is not possible to use the designed access system, provide ladders, scaffolds, or work platforms to perform safe repair operations.
Because of the size of some of the truck components, the serviceman or mechanic should check the weights noted in this Manual. Use proper lifting procedures when removing any components. Following is a list of basic precautions that should always be observed. 1. Read and understand all warning plates and decals on the truck before operating, lubricating or repairing the product. 2. Always wear protective glasses and protective shoes when working around trucks. In particular, wear protective glasses when pounding on any part of the truck or its attachments with a hammer or sledge. Use welders gloves, hood/goggles, apron and other protective clothing appropriate to the welding job being performed. Do not wear loose-fitting or torn clothing. Remove all rings from fingers when working on machinery. 3. Do not work on any truck that is supported only by lift jacks or a hoist. Always use blocks or jack stands to support the truck before performing any disassembly.
6. To avoid back injury, use a hoist when lifting components which weigh 23 kg (50 lb.) or more. Make sure all chains, hooks, slings, etc., are in good condition and are of the correct capacity. Be sure hooks are positioned correctly. Lifting eyes are not to be side loaded during a lifting operation. 7. To avoid burns, be alert for hot parts on trucks which have just been stopped and hot fluids in lines, tubes and compartments. 8. Be careful when removing cover plates. Gradually back off the last two bolts or nuts located at opposite ends of the cover or device and pry cover loose to relieve any spring or other pressure, before removing the last two bolts or nuts completely. 9. Be careful when removing filler caps, breathers and plugs on the truck. Hold a rag over the cap or plug to prevent being sprayed or splashed by liquids under pressure. The danger is even greater if the truck has just been stopped because fluids can be hot.
10. Always use tools that are in good condition and be sure you understand how to use them before performing any service work. 11. Reinstall all fasteners with same part number. Do not use a lesser quality fastener if replacements are necessary. Do not mix metric fasteners with standard nuts and bolts. 12. If possible, make all repairs with the truck parked on a level, hard surface. Block truck so it does not roll while working on or under truck. 13. Disconnect battery and discharge any capacitors (electric trucks) before starting to work on truck. Hang “Do not Operate� tag in the Operator’s Compartment. 14. Repairs, which require welding, should be performed only with the benefit of the appropriate reference information and by personnel adequately trained and knowledgeable in welding procedures. Determine type of metal being welded and select correct welding procedure and electrodes, rods or wire to provide a weld metal strength equivalent at least to that of parent metal. 15. Do not damage wiring during removal operations. Reinstall the wiring so it is not damaged nor will it be damaged in operation by contacting sharp corners, or by rubbing against some object or hot surface. Do not connect wiring to a line containing fluid. 16. Be sure all protective devices including guards and shields are properly installed and functioning correctly before starting a repair. If a guard or shield must be removed to perform the repair work, use extra caution. 17. Always support the mast and carriage to keep carriage or attachments raised when maintenance or repair work is performed, which requires the mast in the raised position.
18. Loose or damaged fuel, lubricant and hydraulic lines, tubes and hoses can cause fires. Do not bend or strike high pressure lines or install ones which have been bent or damaged. Inspect lines, tubes and hoses carefully. Do not check for leaks with your hands. Pin hole (very small) leaks can result in a high velocity oil stream that will be invisible close to the hose. This oil can penetrate the skin and cause personal injury. Use cardboard or paper to locate pin hole leaks. 19. Tighten connections to the correct torque. Make sure that all heat shields, clamps and guards are installed correctly to avoid excessive heat, vibration or rubbing against other parts during operation. Shields that protect against oil spray onto hot exhaust components in event of a line, tube or seal failure, must be installed correctly. 20. Relieve all pressure in air, oil or water systems before any lines, fittings or related items are disconnected or removed. Always make sure all raised components are blocked correctly and be alert for possible pressure when disconnecting any device from a system that utilizes pressure. 21. Do not operate a truck if any rotating part is damaged or contacts any other part during operation. Any high speed rotating component that has been damaged or altered should be checked for balance before reusing.
GENERAL INFORMATION
Model View
103235
Truck Models Covered This Service Manual furnishes servicing and maintenance information for the following trucks: Truck model
Model code – Serial number
Engine mounted
GP40K
ET29B – 00011- up
GM4.3L gasoline engine
GP40KL
ET29B – 50001- up
GM4.3L gasoline engine
GP45K
ET29B – 80001- up
GM4.3L gasoline engine
GP50K
ET33A – 50001- up
GM4.3L gasoline engine
DP40K
ET19C – 00011- up
Mitsubishi S6S diesel engine
DP40KL
ET19C – 50001- up
Mitsubishi S6S diesel engine
DP45K
ET19C – 80001- up
Mitsubishi S6S diesel engine
DP50K
ET28B – 50001- up
Mitsubishi S6S diesel engine
1-1
GENERAL INFORMATION
Serial Number Locations
Chassis serial number Name plate
(Gasoline- and LP-Gasengine models)
(Diesel-engine models)
(Gasoline- and LP-Gas-engine models)
Mast serial number
Transmission serial number
(Diesel-engine models)
Engine serial number
208804
1-2
GENERAL INFORMATION
Chassis and Mast Model Identification
[Chassis] GP
40
K
Generation designator
Maximum capacity/Load center 40: 4000 kg (8000 lb)/500 mm (20 in.) 40L: 4000 kg (8000 lb)/600 mm (24 in.) 45: 4500 kg (10000 lb)/600 mm (24 in.) 50: 5000 kg (11000lb)/600 mm (24 in.) Engine type GP: gasoline engine type DP: diesel engine type [Mast] 4
V
40
A
33
Maximum lifting height [“33” stands for 3300 mm (130 in.)] Order of the minor change (“A” for the original, “B” for the first change, “C” for the second change, and so on) Applicable truck model designation 40: 4 ton class 40L: 4 ton class 45: 4.5 ton class 50: 5 ton class Kind of mast V: simplex mast F: duplex mast M: triplex mast Major change (“2” for the original, “3” for the first change, and so on up to “9”) 1-3
GENERAL INFORMATION
Dimensions
G
K
C
L
E J
A
I
H B
P
D
N
M
O
F
202762A
1-4
GENERAL INFORMATION
Unit: mm (in.) Ref. No. Item
Truck Model
A
Maximum lift
B
Free lift
C
Fork spread (outside)
D
Fork length
E
Tilt angle (forward – backward)
F
Overall length
G
Overall width (outside of tires)
GP40K DP40K
150 (5.9)
6° – 10° 4290 (168.9)
Overall height (to top of mast lowered)
I
Overall height (to top of overhead guard)
J
Overall height (mast extended)
K
Tread (front)
Wheelbase
N
Front overhang
O
Rear overhang
P
Underclearance (at frame)
160 (6.5)
1220 (48)
H
M
GP50K DP50K
300 to 1190 (12 to 47)
4340 (170.9)
1415 (55.7)
Dual tire
Tread (rear)
GP45K DP45K
3300 (130)
Single tire
L
GP40KL DP40KL
4395 (173.0)
4525 (178.2)
1460 (57.5) 1780 (70.1)
1965 (77.4)
2320 (91.5)
2400 (94.5) 2250 (88.6)
4430 (174.4)
4580 (180.5)
Single tire
1175 (46.5)
Dual tire
1310 (51.5) 1180 (46.5) 2000 (78.5) 557 (21.9) 513 (20.6)
563 (22.6)
2150 (84.5) 562 (22.1)
582 (22.9)
613 (24.4)
573 (22.6)
252 (9.9)
1-5
GENERAL INFORMATION
Technical Data Truck Model Item
GP40K DP40K
GP40KL DP40KL
Model code
GP45K DP45K
GP: ET29B DP: ET19C
Type
General
Maximum lift
4000/500 (8000/20)
4000/600 (8000/24)
mm (in.)
Lift speed (rate load) mm/sec (fpm)
GP: 510 (100) DP: 500 (98)
GP: 440 (87) DP: 430 (85) 500 (100)
Tilt angle (forward – backward)
6° – 10°
mm (in.)
Minimum turning radius mm (in.)
5000/600 (11000/24)
3300 (130)
Travel speed of Forward powershift transmission models km/h (mph) Reverse Performance
4500/600 (10000/24)
Lowering speed (rate load) mm/sec (fpm)
Free lift
2735 (107.7)
GP: 430 (85) DP: 420 (83)
150 (5.9)
160 (6.5)
19.5 (12)
23.5 (15)
19.5 (12)
23.5 (15)
2775 (109.3)
Inside
2820 (111)
2965 (116.7)
83°
Steering angle Outside Minimum Single tire intersecting aisle mm (in.) Dual tire Front tires (size and inflation pressure)
Tires
GP: ET33A DP: ET28B Standard
Capacity/load center kgf/mm (lbf/in.)
kPa (kgf/cm2) [psi]
Single tire
56°33’ 2390 (94.1)
2430 (95.7)
2450 (96.5)
2510 (98.8)
2570 (101)
2590 (102)
2620 (103)
2670 (105)
8.25-15-14PR (I) 785 (8.0) [114]
300-15-18PR (I) 785 (8.0) [114] 7.50-16-12PR (I) 686 (7.0) [99.5]
Dual tire
Rear tires (size and inflation pressure) kPa (kgf/cm2) [psi] Truck weight
GP50K DP50K
7.00-12-14PR (I) 686 (7.0) [99.5]
834 (8.5) [121]
Single drive tire (unloaded) GP: 5630 (12400) kg (lb) DP: 5710 (12600)
GP: 6030 (13300) DP: 6120 (13500)
GP: 6600 (14500) DP: 6680 (14700)
GP: 7080 (15600) DP: 7160 (15800)
Dual drive tire (unloaded) GP: 5810 (12800) kg (lb) DP: 5900 (13000)
GP: 6160 (13600) DP: 6250 (13800)
GP: 6730 (14800) DP: 6820 (15000)
GP: 7250 (15900) DP: 7320 (16100)
1-6
GENERAL INFORMATION
Truck Model GP40K
GP40KL
GP45K
Item Engine model
GM4.3L
Manufacturer
General Motors
Type
Gasoline
Cooling system
Water cooled
No. of cylinders – arrangement
6 – 90° V
No. of strokes
4
Type of combustion chamber
Semi -spherical
Valve arrangement
Overhead
Type of cylinder liners
Integral
Engine (gasoline and LP-gas)
Cylinder bore × stroke
Displacement
mm (in.)
101.6 × 88.39 (4.00 × 3.48)
cc (cu in.)
4293 (262)
Compression ratio Rated output
9.2 : 1 kW/rpm
69.5/2450
Maximum torque N·m (kgf·m) [lbf·ft]/rpm
305 (31.0) [224]/1200
Low idle engine speed
rpm
750
High idle engine speed
rpm
2450
Dimensions (L × W × H) mm (in.) Weight
710 × 620 × 740 (28.0 × 24.4 × 29.1)
kg (lb)
260 (573)
Installation position
Rear
Ignition
Spark
Firing order
1–6–5–4–3–2
Initial ignition timing BTDC deg
0° Gasoline/ 8° L.P.G.
Fuel tank capacity liter (U.S. gal)
115 (30)
1-7
GP50K
GENERAL INFORMATION
Truck Model GP40K
GP40KL
GP45K
Item
Ignition system
Ignition coil
Distributor
Type
Mold
Manufacturer
AC Delco
Type
Pointless
Manufacturer
AC Delco
Type of spark advance control
Internal solid state circuit
Model
#41-932
Manufacturer
AC Delco
Size
mm (in.)
14 (0.55)
Gap
mm (in.)
1.24 (0.0488)
Spark plug
Fuel system
Type
1FZ
Carburetor Manufacturer
AISAN Kogyo Co.
Type
Electromagnetic
Fuel pump
Air cleaner
Manufacturer
Jidosha Kiki
Type Ă— Number
Cyclone with paper element Ă— 1
Manufacturer
Nippon Rokaki
Engine lubrication system
Type
Pressure feed
Oil pump
Gear pump
Oil filter
Paper element
Oil cooler
Oil to water type
Refill capacities
Oil pan liter (U.S. gal)
4.2 (1.1)
Oil filter & cooler liter (U.S. gal)
0.8 (0.2)
Total liter (U.S. gal)
5.0 (1.3)
1-8
GP50K
GENERAL INFORMATION
Truck Model GP40K
GP40KL
GP45K
Item
Battery
Cooling system
Type
Forced circulation
Radiator Refill capacity
Corrugated fin with pressure type liter (U.S. gal)
17.2 (4.5)
Water pump
Centrifugal type driven by V-belt
Thermostat
Wax type
Type × number
48D26L
Voltage Capacity
V
12
AH (5 Hr)
50
Starter
Alternator
Type
3-phase AC
Manufacturer Rated output
MANDO V–A
12 – 50
Regulator
Built-in IC type
Type
Electromagnetic
Manufacturer Voltage – output
Delco Remy V – kW
12 – 0.75
1-9
GP50K
GENERAL INFORMATION
Truck Model DP40K
DP40KL
DP45K
Item Engine model
S6S
Manufacturer
Mitsubishi Heavy Industries, Ltd.
Type
Water-cooled, 4-stroke cycle
No. of cylinders – arrangement
6 – in-line
Type of combustion chambers
Swirl
Valve arrangement
Overhead
Type of cylinder liners
Dry
Bore × stroke
mm (in.)
94 × 120 (3.70 × 4.72)
Displacement
cc (cu in.)
4996 (305)
Compression ratio
Engine (diesel)
Rated output
22 : 1 kW/rpm
62.5/2450
Maximum torque N·m (kgf·m) [lbf·ft]/rpm
250 (25.5) [184]/1600
Dimensions (L × W × H) mm (in.)
907.5 × 639 × 801 (35.7 × 25.2 × 31.5)
Weight (service)
kg (lb)
350 (771)
Installation position Intake valves
Exhaust valves
Valve clearance (at cold)
Open
Rear BTDC deg
30°
Close ABDC deg
50°
Open
BBDC deg
74°
Close ATDC deg
30°
Intake valves mm (in.) 0.25 (0.0098) Exhaust valves mm (in.)
Ignition
Compression
Firing order
1–5–3–6–2–4
Ignition or injection timing BTDC deg
19°
1-10
DP50K
GENERAL INFORMATION
Truck Model DP40K
DP40KL
DP45K
Engine (diesel)
Item Fuel tank capacity
115 (30)
liter (U.S.gal) No-load minimum speed
rpm
650
No-load maximum speed
rpm
2450
Type
Bosch
Manufacturer
Fuel system
Fuel injection pump
Fuel injection nozzles
Glow plugs
Nippon Denso
Plunger diam. mm (in.)
6.5 (0.256)
Cam lift (one side) mm (in.)
6 (0.24)
Type
Throttle
Spray holes diam. mm (in.)
1.0 (0.04)
Injection pressure kPa (kg/cm2) [psi]
1372 (140) [1992]
Type
Sheathed
Voltage – current V– A
22 – 4.4
Type
Plunger
Fuel pump Manufacturer
Nippon Denso
Type × number
Cyclone with paper element × 1
Air cleaner
Lubrication system
Manufacturer
Nippon Rokaki
Type
Pressure feed
Oil pump
Trochoid type
Oil filter
Paper element type
Oil pan Refill capacities Oil filter liter (U.S. gal) Total
11 (2.9) 1 (0.3) 12 (3.2)
1-11
DP50K
GENERAL INFORMATION
Truck Model DP40K
DP40KL
DP45K
DP50K
Item
Cooling system
Type
Forced circulation
Radiator
Corrugated fin with pressure cap
Refill capacity
14.7 (3.9)
liter (U.S. gal) Water pump
Centrifugal type driven by V-belt
Thermostat
Wax type
Alternator and regulator
Battery
Type × number
48D26R × 2
Voltage
V
24
Capacity
Ah
50
Alternator type
3-phase AC Transmission cooling
Capacity
Water cooling
V–A
24 – 35
Starter
Voltage/current regulator IC type
Built-
Type
Voltage – output
Engine stop device
Stop solenoid
Mitsubishi Electric Corporation V – kW
24 – 5
Manufacturer Setting
Shin Dengen Kogyo sec
5 to 7
Operating voltage V Rated current (at 24 V)
16 to 30
11.3
V
Mitsubishi Electric Corparation
Manufacturer Detector (magnetic
Oil cooling
Electromagnetic
Manufacturer
Control timer
Manufacturer Mitsubishi Electric Corporation
Output
mA
180 minimum
1-12
GENERAL INFORMATION
Truck Model Item
GP40K DP40K
GP40KL DP40KL
GP45K DP45K
Type
Dry, single disc (OP: wet type)
Clutch Facing (OD × ID), (DP40K thru mm (in.) DP45K)
325 × 210 (12.8 × 8.3) [wet: 325 × 225 (12.8 × 8.9)]
Material
DR-8 (wet: cork)
Type Torque converter
3-element, 1-stage, 2-phase
Manufacturer’s model
Okamura M15
Stall torque ratio
3.2
Control and shift Powershift transmission
GP50K DP50K
Hydraulic and column shift
Forward
4.044
F1: 5.735 F2: 3.239
Reverse
4.057
R1: 5.735 R2: 3.239
Power train
Ratios
Manual transmission (DP40K thru DP45K)
Type
Synchro-mesh
Shift
Floor-shift
Forward ratio
Reverse ratio
1st
8.462
2nd
4.145
1st
8.489
2nd
4.159
Type of gear
Spiral bevel
Reduction gear
Differential
Gear ratio
4.857
Housing
Banjo
Type of gear – number
Straight bevel – 2
Type of pinion – number
Straight bevel – 4
1-13
GENERAL INFORMATION
Truck Model Item
GP40K DP40K
GP40KL DP40KL
Type
GP45K DP45K
Recirculating ball-and-nut
Gear ratio
20.0
Steering system
Steering wheel diameter mm (in.)
380 (15)
Type
Power steering
Semi-integral
Power cylinder ID × rod diam. mm (in.)
55 × 25 (2.17 × 0.98)
Effective stroke mm (in.)
275 (10.8)
Relief pressure kPa (kgf/cm2) [psi]
8336
Traveling system
Flow rate liter (U.S. gal)/min
+ 490 0
(85
) [1209
+ 71 0
Full-floating tubular type
Rear axle
Elliott type
Suspension Front system Rear
Fixed type
Toe-in
Center-pivot type mm (in.)
0
Camber
1.0°
Caster
0° 5.0°
Type
Self-adjusting, duo-servo
Drum diameter mm (in.) Wheel brakes
Parking brake
]
17.5 ± 0.5 (4.6 ± 0.13)
Kingpin inclination
Brake system
+5 0
Front axle
Wheel alignment
GP50K DP50K
317.5 (12.50)
Lining (length × width × thickness − number) mm (in.)
351 × 60 × 6 − 2 (13.8 × 2.4 × 0.2 − 2)
332 × 63 × 10 − 2 (13.1 × 2.5 × 0.4 − 2)
Master cylinder ID mm (in.)
22.22 (0.8748)
25.4 (1.000)
Wheel cylinder ID mm (in.)
28.58 (1.1252)
31.75 (1.2500)
Type
Mechanical, mounted on wheels
Brake booster
Mastervac (vacuum suspended)
Body
Assembled-frame type
1-14
GENERAL INFORMATION
Truck Model Item
GP40K DP40K
GP40KL DP40KL
Type
Shimazu
Hydraulic Manufacturer’s type pump Rated discharge liter (U.S. gal)/rpm
Hydraulic system
SGP2B50L979 110 (29.0)/2450
Drive line
Universal joint
Type
KVS-120VPF-2
Manufacturer
Kayaba
Relief pressure MPa (kgf/cm2) [psi] Flow regulator valve
Lift cylinders
Tilt cylinders
GP50K DP50K
Gear
Manufacturer
Control valve
GP45K DP45K
19.1 (195) [2773]
Type
Variable (Adjustable)
Regulated flow rate liter (U.S. gal)/min ID
mm (in.)
Stroke
mm (in.)
ID
mm (in.)
Stroke
mm (in.)
100 (26.4) 65 (2.56
115 (30.4)
+ 0.1 0 + 0.004 0
70 (2.76
)
+ 0.1 0 + 0.004 0
)
1500 (59.06) 80 + 00.1 + 0.004 (3.15 0 )
90 + 00.1 + 0.004 (3.54 0 ) 185 (7.28) L: 56.5 (14.9) N: 58.7 (15.5) H: 64.4 (17.0)
Hydraulic tank capacity liter (U.S. gal)
1-15
COOLING SYSTEM
Structure
1 6 5 8 5 4
10
1
2 3 2
3 207009
208411 8
Transmission cooling
Water cooling
9 Oil cooling
7
6 9 208413
1 2 3 4 5
Engine Universal joint Gear pump Fan belt Cooling fan
6 7 8 9 10
2-1
Upper hose Lower hose Radiator Oil cooler hoses Tension pulley
COOLING SYSTEM
Removal and Installation Fan Belt Removal
3 1 2 (Only loosen.)
208414
Sequence 1 2 3
Universal joint Tension pulley assembly, Bolt Fan belt
Start by:
Remove the radiator cover.
Suggestion for removal
Tension pulley assembly
(1) Using a ratcheting wrench inserted in the gap between the weight and frame, loosen the tension pulley lock bolt by three or four turns. If the bolt is loosened insufficiently, the tension pulley will not be moved.
A
A
NOTE Do not loosen the lock bolt to such an extent that the tension pulley would be removed. (2) Move the tension pulley fully toward the fan, then remove the belt. 2-2
Tension pulley lock bolt
Section A–A
208415
COOLING SYSTEM
Installation Perform installation by following the removal sequence in reverse. Also follow the instructions given below. (1) Before installing the belt, turn the fan to check for smooth rotation. Replace the bearing if it generates abnormal sound. (2) After installing the belt, push it at a point midway between the driven and drive pulleys to make sure that the tension pulley moves, then tighten the pulley lock bolt firmly.
Fan Assembly Removal
1 3 2
208416
Sequence 1 2 3
Fan cover Fan assembly Tension pulley assembly
Start by:
Remove the radiator cover.
Suggestion for removal Remove the fan support bolts, detach the belt from the driven pulley, and then remove the fan assembly. Place the fan assembly with the fan support facing down and turn the fan to check for smooth rotation. Replace the bearing if it generates abnormal sound.
2-3
COOLING SYSTEM
Installation Perform installation by following the removal sequence in reverse. Also follow the instruction given below. (1) With the tension pulley lock bolt loosened, attach the belt to the driven pulley (fan assembly pulley), then screw in the bolt at the bottom of the fan support; do not tighten the bolt yet. Holding the fan support by its top, move the support until it reaches the boss (frame), then tighten all the fan support bolts. (2) Adjust the tension of the fan belt.
2-4
COOLING SYSTEM
Inspection and Adjustment Fan belt condition (1) Check the belt for contamination with oil, grease and/or dust. If the contamination is slight, remove it clean with rag or wiping paper. Do not use gasoline, oil or any other solvent to clean the belt. (2) During engine overhaul or belt tension adjustment, closely check the belt for condition. Replace the belt with a new one if it has any sort of damage.
Fan belt tension Apply a force of 98 N (10 kgf) [22 lbf] perpendicularly to the belt at a point midway between the fan pulley and tension pulley. If necessary, adjust the tension by moving the tension pulley assembly such that the belt deflects 16 mm (0.63 in) when pressed with the above force. After adjustment, tighten the tension pulley assembly lock bolt firmly.
Connecting Radiator Hoses When connecting the hoses to the radiator, fit their ends fully on the fittings and secure them with clamps. Tighten the clamp bolts to the torques indicated below. Make sure that each hose is correctly retained and prevented from disconnection by the flare of the fitting.
Clamp bolt tightening torques
Upper and lower hoses
Cooler hose
3.92 to 5.88 N·m (0.4 to 0.59 kgf·cm) [2.9 to 4.3 lbf·ft] 2.94 to 4.9 N (0.3 to 0.5 kgf) [2.2 to 3.6 lbf]
2-5
COOLING SYSTEM
Coolant Fill the radiator with coolant containing antifreeze. Start and operate the engine to let it warm up while checking for abnormal noise. Make sure that the quantity of coolant is as specified by checking the level in the reserve tank.
Quantity of coolant
Unit: liter (U.S. gal) Truck Model
GP40K, GP40KL, GP45K, GP50K Powershift transmission models
DP40K, DP40KL, DP45K, DP50K Powershift transmission models
Engine
11 (2.9)
7.1 (1.9)
Radiator
4.3 (1.1)
4.7 (1.2)
Reserve tank (FULL level)
0.65 (0.17)
0.65 (0.17)
Total quantity of coolant (including coolant in hoses)
17.2 (4.5)
14.7 (3.9)
Oil cooler
0.62 (0.16)
0.31 (0.08)
Item
Radiator Cap Opening pressure
Vacuum valve
90 ± 15 kPa (0.92 ± 0.15 kgf/cm2) [13.1 ± 2.2 psi] 0 to 5 kPa (0 to 0.05 kgf/cm2) [0 to 0.73 psi]
2-6
ELECTRICAL SYSTEM
Structure and Functions Console Box 1 2 3 4 5 6 7 8 9
Engine coolant temperature gauge Travel speed select switch Fuel gauge (for diesel-engine models) Service hourmeter OK monitor Starter switch Lighting switch Fuse box Auto-light switch (for FC models)
103249
3-1
ELECTRICAL SYSTEM
OK Monitor
103239
Function
No.
Indicator light
OFF
ON or flickering
Remarks
1
Powershift transmission oil temp. indicator light
Normal
Overheating
2
Air cleaner element indicator light
Normal
Clogged
3
Brake fluid level indicator light
Normal
Low
4
Engine oil pressure indicator light
Normal
Low
5
Alternator not charging indicator light
Normal
Abnormal
6
Heater plug indicator
Normal
7
LP-Gas residual pressure alarm lamp
Normal
Drain water
Option
8
System indicator light
Normal
Abnormal
FC models
9
Engine coolant level indicator light
Normal
Low
Option
Option
Diesel-engine models
How to check indicator light bulbs
The bulbs are normal if all the indicator lights come ON when the starter switch key is turned to the position. (The indicator lights will go OFF when the engine starts.)
Truck Model
Indicator light No.
MC diesel-engine model
1, 2, 3, 4, 5, 6
MC LPG-engine model
1, 2, 3, 4, 5
FC diesel-engine model
1, 2, 3, 4, 5, 6, 8
FC LPG-engine model
1, 3, 4, 5, 8
3-2
(ON)
ELECTRICAL SYSTEM
Electrical Components Mounted on Body
208773
1 2 3 4 5 6
Main harness Fusible link (R.H.) Fusible link (L.H.) Fuse Fuse Power relay (FC model)
7 8 A: B:
3-3
System harness Harness (tilt earth) To forward/reverse lever To turn signal switch
ELECTRICAL SYSTEM
Disassembly and Reassembly Console Box
208774
Disassembly
Reassembly
1. Disconnect the electrical wires at connectors 1.
To reassemble the console box, follow the reverse of disassembly procedure.
(Disconnect the choke cable on the engine side.) 2. Remove four screws 2 securing the cover. 3. Remove six screws 3 and separate the front and rear panels. 4. Remove four screws 4 securing the instrument panel.
NOTE To replace the instrument panel bulbs, remove screws 3 and 4.
3-4
ELECTRICAL SYSTEM
Console Box
208789
Disassembly
Reassembly
1. Remove two screws 1 securing the cover. (Use a flat-tip screwdriver)
To reassemble the console box, follow the reverse of disassembly sequence.
2. Remove six screws 2 and separate the front and rear panels. 3. Remove four screws 3 securing the instrument panel.
NOTE To replace the instrument panel bulbs, remove screws 2 and 3.
3-5
ELECTRICAL SYSTEM
Components in Console Box
9 6 5
4 3 2 7
1
8
208556
1 2 3 4 5
Power relay Power relay (diesel-engine models) Turn signal relay Glow plug relay (diesel-engine models) Glow plug timer (diesel-engine models)
6 7 8 9
3-6
Lighting switch Starter switch Fuses Travel speed select switch
ELECTRICAL SYSTEM
Combination Meter Disassembly
1
2 3 4
5
6
7 8 9 206480
Sequence 1 2 3 4 5
Instrument panel Dial Engine coolant temperature gauge Service hourmeter Fuel gauge (diesel-engine models)
6 7 8 9
Meter case Printed circuit plate Bulb Socket
CAUTION Be careful not to damage the printed circuit plate when disassembling the combination meter.
Reassembly
Bulb replacement
To reassemble the combination meter, follow the reverse of disassembly sequence.
For bulb replacement, remove the socket from the printed circuit plate by turning it to the left. For configuration of the indicator lights, refer to the preceding section “OK Monitor�. 3-7
ELECTRICAL SYSTEM
Major Electrical Components Starter Switch (with Anti-Restart Lock) engine models use the same starter switch. In the diesel-engine models, (ON) position of the switch is for energizing the glow plugs.
This switch has a built-in anti-restart lock, so the key cannot be turned from (ON) to (START) position while the engine is running. The LPG- and diesel(OFF) (ON)
(START)
G1
M
B2
G2 B1
S 203561A
Connection chart LPG-engine models (12 V)
Terminal Component Key position
B1, B2
G1
G2
Fuse box, battery, alternator
(OFF)
(ON)
(START)
M
S
Fuse box
G2
M
S
Fuse box
Glow plug timer
Diesel-engine models (24 V)
Terminal Component Key position
B1, B2
G1
Fuse box, glow plug relay, battery, alternator
(OFF)
(ON)
(START)
NOTE The starter switches for both LPG and diesel engines are same in design. With a LPG engine, therefore, turning the key to a position on the left of the OFF position is possible but does not cause any effect as there is no electric circuit connected there. 3-8
ELECTRICAL SYSTEM
Lighting Switch OFF 1st 2nd 8 8 (0.3) (0.3)
Knob position Stroke [Unit: mm (in.)]
206481
Connection chart
B
Terminal Component
Battery (fuse)
Knob position
T Tail lamps, instrument panel lamp
H
P
Head lamps
Clearance lamps
(OFF) 1st position
2nd position
If the insulation resistance between any two terminals is not up to the specification indicated below when the knob is in the OFF position, the lighting switch must be replaced with a new one. Insulation resistance
1 M ohm or higher (as measured by a 500 V megger)
Turn Signal Switch Connection chart
Terminal
L N
RF LF
R
Lever Component position R (Right)
F
RF
Turn signal Turn signal relay (L) (RH)
LF Turn signal (LH)
Green
Yellow
Black
N (Straight) F
L (Left) 203573
Cord color
If the insulation resistance between any two terminals is not up to the specification indicated below when the lever is in the N position, the turn signal switch must be replaced with a new one. Insulation resistance
1 M ohm or higher (as measured by a 500 V megger) 3-9
ELECTRICAL SYSTEM
Fuel Tank Unit
212.4 mm (8.36 in.)
141.4 mm (5.57 in.)
F To fuel gauge 3/4
To ground
Indication accuracy
1/2
Terminal Item
E
1/4
1/2
3/4
F
80
49.5
32
19
10
+ 12 +2
−
±3
−
+ 1.0 − 0.5
1/4
Standard resistance (ohm) Tolerance
E
(ohm)
203574
3-10
ELECTRICAL SYSTEM
Fuse Box A B C D E F G H J
103240
MC Model
FC Model
Gasoline-engine models Code
Capacity
Circuit
A
10 A
B
15 A
C
15 A
D
15 A
E
15 A
Directon lever, delay timer Instrument panel, stop lamp switch, T/M controller Spare power source Head, working (opt) lamps Spare fuse
F
10 A
Spare fuse
Diesel-engine models Capacity 10 A
Gasoline-engine models Code
Circuit
Capacity
Circuit
Directon lever, delay timer Instrument panel, turn signal lamps
A
10 A
B
15 A
C
15 A
D
15 A
10 A
Spare power source Head, working (opt) lamps Horn
E
15 A
Directon lever, delay timer Instrument panel, stop lamp switch, T/M controller Spare power source Auto light switch, working (opt) lamps Head lamps
10 A
Spare fuse F
10 A
G
10 A
10 A 15 A
G
10 A
Horn
10 A
Stop lamps
H
15 A
Spare fuse
10 A
Backup lamps
J
10 A
Spare fuse
15 A
Spare fuse
Diesel-engine models Capacity 10 A
Circuit
15 A
Directon lever, delay timer Instrument panel, stop lamp switch, T/M controller Spare power source Auto light switch, working (opt) lamps Head lamps
FC controller
10 A
FC controller
10 A
Horn
10 A
Horn
H
15 A
Spare fuse
15 A
Backup lamps
J
10 A
Emergency switch
10 A
Emergency switch
15 A
15 A 15 A
Spare Terminals The spare terminal cord extends from the fuse box in the console box. (Another spare terminal is located on the chassis-side main harness.)
Cord color
Lg (light green)
Removing the console box rear panel will expose this spare terminal which is fastened to the harness protector with vinyl tape.
Spare terminal 207209
3-11
ELECTRICAL SYSTEM
Lamp Bulb Specifications Item Type of lamp Head lamps
No. of bulbs
Color of lens
Watts 12 volt 24 volt
2
Colorless
45
60
Turn signals
2
Amber
27
25
Clearance lamps
2
Amber
10
12
Turn signals
2
Amber
27
25
Tail/stop lamps
2
Red
8/23
10/25
Backup lamps
2
Colorless
10
12
2
Colorless
45
60
3 (14 volt)
3
Shape
Remarks
Standard: Installed on overhead guard
Combination lamps (front)
Combination lamps (rear)
Working lamps (front and rear)
OK monitor indicator lamps and instrument panel lamp
8 (Diesel) or Colorless 7 (LPG)
Option
200016A
3-12
ELECTRICAL SYSTEM
Battery Maintenance 1. State of charge and electrolyte specific gravity (S.G.) adjustment
Specific gravity reading at 20°C (68°F)
State of charge
Adjustment
1.280 to 1.265
Fully charged
If difference in S.G. between any two cells is 0.040 or more, effect a high current discharge to minimize the difference and then recharge battery. Adjust S.G. during recharging.
1.260 to 1.225
One-half charged
Recharge battery and adjust electrolyte S.G. Make sure there is neither faulty components, loosely connected cord nor corroded connection.
1.220 or below
Discharged
Recharge battery. If difference in S.G. is large, adjust it during recharging.
If difference in S.G. is more than 0.040
A cell with a low S.G. is in shorted condition. Recharge until voltage and S.G. stabilize and have remained constant for more than 2 hours.
During recharging, adjust S.G. to 1.280 to 1.265. If difference in S.G. is more than 0.040 and a low S.G. is found in certain cells only, replace battery. After leaving battery for 12 to 96 hours, conduct a high current discharge test.
(4) When connecting the cables to the battery, begin with the cable for the positive (+) terminal. When disconnecting them from the battery, begin with the cable for the negative (−) terminal.
2. Specific gravity reading and state of charge
To check the battery for state of charge, take hydrometer readings on its electrolyte. The battery may be fully charged if the S.G. reading is 1.280 to 1.265 at 20°C (68°F). The state of charge can be told from the way the electrolyte level goes down to expose the cell plates. If addition of distilled water is necessary every month or so, the battery is overcharged. If addition is not required for more than 3 months, it is likely that the battery is inadequately charged.
CAUTION Be sure to turn OFF the starter switch and lighting switch before disconnecting or connecting the battery cables to prevent the IC regulator from suffering damage.
3. Charging precautions
(1) In slow charging, the charging current should be about 1/10 the capacity of the battery to be charged. (2) In quick charging, the battery capacity in ampere should not be exceeded. (3) During charging, adjust the charging current to prevent the electrolyte temperature from rising beyond 45°C (113°F).
3-13
ELECTRICAL SYSTEM Precautions for servicing charging system (with alternator)
The alternator is equipped with a built-in IC (integrated circuit) voltage regulator. When servicing the charging system, pay attention to the following precautions: (1) Do not reverse the polarity of the battery. (2) Do not disconnect the battery terminal while the engine is running.
Terminal L
(3) Do not ground the terminal L. Terminal R
(4) Do not short the terminals L and R. (5) Do not direct a blast of steam cleaner to the alternator. Remember, a blast of steam will damage the IC regulator.
3-14
Terminal B
202772
ELECTRICAL SYSTEM
FC (Finger-Tip-Control System) Nomenclature 5
1
6
2
3 7 8 9 4
103237
1 2 3 4 5
Light sensor Auto-light switch Flow regulator valve Solenoid control valve Seat switch
6 7 8 9
3-15
Lowering speed selector switch Safety switch Joystick levers (finger-tip-control system) Controller
ELECTRICAL SYSTEM
Maintenance Precautions The FC model contains a microcomputer. Following are the precautions to be observed in performing any maintenance on the FC model. (1) When removing the controller cover, make proper provisions to keep out rain, washing water splashes and the like. (2) After using the controller setting switch, check to make sure the control system is in keeping with the truck specifications.
NOTE
208775
Improper setting of the system will result in inability to lower the forks in an inching manner. (See “How to Set Controller�.)
(3) Before performing repairs which require welding, be sure to disconnect the cable from the battery positive (+) terminal and the controller from the system at its connectors. (4) When handling the controller by hand, never touch its electrical terminals, or your body charge will rupture some of the electronic elements in the internal controller circuits.
3-16
208776
ELECTRICAL SYSTEM
Description 1. Finger-tip-control system
This system, unlike the conventional mechanical control, is electronically actuated to help reduce the effort required of the operator in moving the control levers for lift, tilt and attachment functions.
101466B
[Features]
(1) The lowering speed selector switch insures smooth fork and mast movement no matter how abruptly the operator may move the control levers. This switch is ideal for handling of fragile loads.
ON: 350 mm/s (69 fpm) OFF: 500 mm/s (98 fpm) 204992B
(2) This system provides the following safety functions: (a) The lift, tilt and attachment functions are not performed even if the control levers are moved when the engine is not running.
(d) The system indicator light in the OK monitor alerts the operator to problems occurring in the electrical system and, at the same time, stops function. (If any problem occurs in the lift system, for example, the system becomes inoperative.)
(b) The lift, tilt and attachment functions are not performed even if the control levers are moved when the safety switch is in ON (pushed) position. (c) The lift, tilt and attachment functions are not performed even if the control levers are moved when the seat switch is not ON (the operator is not seated).
3-17
ELECTRICAL SYSTEM 2. Auto-light system
The head lamps are under the control of switch and sensor. With the auto-light switch ON, the head lamps turns ON automatically as the truck is driven into a dark area. The head lamps can be turned ON or OFF manually.
101489
Operating Principles 1. Finger-tip-control system
(1) The system is activated by turning ON the safety switch when the engine is running and the seat switch is ON (when the operator is seated). (2) As the control levers (joysticks) are moved to operate the equipment (mast and forks), the amount of lever movement will be translated into an electrical signal: this signal goes into the controller, in which it is converted to and output signal. At this point the controller issues and ON signal to the unload solenoid, thereby turning ON this solenoid to introduce hydraulic pressure into the control valve. The system is now ready to actuate the equipment. The output signal applies to the proportioning solenoid selected by the direction of the joystick movement. Inside the control valve of that solenoid, its spool is forced to slide, altering the internal oil passage to direct the oil to the corresponding cylinders. The spool keeps on sliding until it comes to the position at which the pressure of its pilot chamber becomes equal to the force of its centering spring. In the meantime, the cylinder extends or retracts against its load. As the joystick is moved back to its neutral position, the signal to the proportioning solenoid dies to lower the pilot chamber pressure and allow the centering spring to push the spool to its neutral position, whereby the line to the cylinder becomes shut off: the pressure in the line is now trapped, holding the cylinder there. At the same time, the ON signal to the unload solenoid goes OFF, so that the part of the system actuating the equipment goes into no-load state.
3-18
ELECTRICAL SYSTEM
(3) Power supply to the controller is initiated from the starter switch through a 10-Amp fuse and safety switch. Pressing this switch into OFF position shuts down the controller without shutting down the engine. (4) With the starter switch and safety switch turned ON, the unloading solenoid and proportioning solenoid are under control of the joysticks. With the engine shut down (and hence the hydraulic pump standing still), the spools in the control valves are inoperative because no pressure develops in their pilot chambers. Consequently, the equipment remains inoperative even when the starter switch and safety switch are turned ON.
3-19
Lift cylinder
Fuse 10 A
3-20 Hydraulic pump
Unload solenoid
Starter switch (ON)
System indicator light
Console box
Finger-tip-control system schematic
Solenoid control valve
Proportioning solenoid
Seat switch (ON)
Spool
Safety switch (ON)
Pilot pressure passage
Centering spring
Pilot pressure passage
Proportioning solenoid
Power supply
Power supply
Lowering speed selector switch
Flow control signal
Detail of control valve
Control lever (joystick)
Control (joystick) box
Battery
Lever stroke signal
ON-OFF signal
Power supply
Setting window
Controller
ON-OFF signal
ON-OFF signal
Safety switch (OFF)
208777
ELECTRICAL SYSTEM
ELECTRICAL SYSTEM
(5) In addition to the functions explained above, the controller monitors the supply voltage and the electrical connections for the control levers (joysticks), solenoids and other input/output devices, and alerts the operator to a problem, if occurs, by flickering the system indicator light and turning ON this light and also LED (as shown in the chart below). Such a problem is usually a fault in the harness or connector and must be located by inspecting. The hydraulic components such as pump control valve, etc. are not monitored.
LED flickers
LED flickers
LED flickers
LED flickers LED flickers
LED flickering pattern
1.2 sec.
1.2
1.2
Problem detected
208778
Effect
1.2
(Normal)
0.3
2.1
System indicator light
0.3
2.1
OFF
Open- or short-circuit in control lever (with starter switch in ON position)
No power supply to particular system
ON
Supply voltage too high (over No power supply 32 volts or too low under 9 volts) to all systems
0.6 0.6
ON
1.2
0.6 0.6 0.6 0.6
1.2
Open- or short-circuit in solenoid
No power supply to particular system
Control lever neutral position displaced
No power supply to particular system Flickers
Open- or short-circuit in control lever (with starter switch in ON position) 1.2
0.3 0.6
LED remains ON
0.3 0.6
0.6
0.3 0.9
Seat switch OFF, of open-circuit in it
No power supply to all systems
Flickers
Problem in controller
NOTE: Any problem does not cause the engine to shut down. 204995A
3-21
ELECTRICAL SYSTEM 2. Auto-light system
Example: The auto-light system functions regardless of ON-OFF of the seat switch. The fingertip-control system functions even if the light sensor is faulty.
(1) The auto-light system turns ON the head lamps automatically when the truck is driven into a dark area, with the starter switch in (ON) position, the safety switch ON and the auto-light switch ON. The controller is common to this system and the finger-tip-control system but the circuit of the system is independent so the components of these systems do not affect each other in operation.
Light sensor 208779
208780
Auto-light switch
Power relay 102454
208781
Major Components of Auto-light System
NOTE The controller has no auto-light system diagnosing function.
3-22
ELECTRICAL SYSTEM
(2) The light sensor is basically a resistance device, whose resistance is compared with that in the variable resistor (the auto-light sensitivity adjusting knob) inside the controller. The sensor resistance increases as brightness decreases. When, in operation, the sensor resistance becomes greater than the resistance in the variable resistor, the comparing circuit energizes the power relay to close its contacts to turn ON the head lamps. With auto-light switch ON, starter switch (ON) and safety switch ON Control (joystick) box Head lamp
Instrument panel lamp Power supply
Tail lamp Console box Clearance lamp
B
PHT
Lighting switch
Safety switch (ON)
Starter switch (ON) Controller (ON)
10 A 20 A
Auto-light switch (ON)
Battery
Dark Light sensor
Setting window
Power relay (ON)
Auto-light sensitivity adjusting knob 208782
Operation–1
3-23
ELECTRICAL SYSTEM
(3) With the auto-light switch turned OFF, the lighting switch can be used to turn ON a light selected by the position of this switch. Even under this condition, the power relay goes ON or OFF in response to changes in ambient brightness but this does not affect the light turned ON by the lighting switch. With the auto-light switch OFF, the starter switch (ON) and the safety switch ON. With auto-light switch OFF, starter switch (ON) and safety switch ON Control (joystick) box Head lamp Instrument panel lamp Power supply
Tail lamp Clearance lamp
Console box B
PHT
Lighting switch
Safety switch (ON)
Starter switch (ON) Controller (ON)
10 A 20 A
Auto-light switch (OFF)
Battery Setting window
Dark Light sensor
Power relay (ON)
208783
Operation–2
3-24
ELECTRICAL SYSTEM
(4) Turning OFF the safety switch with the auto-light switch ON causes the power relay to remain OFF. Under this condition, all lamps will not come ON. If the auto-light switch is OFF, the lighting switch is effective and can turn ON each selected light, regardless of the safety switch and starter switch. With auto-light switch ON and safety switch ON Control (joystick) box Head lamp Power supply
Tail lamp Clearance lamp
Console box B
P HT
Safety switch (OFF)
Lighting switch Starter switch
Controller (OFF)
10 A 20 A
Auto-light switch (ON)
Battery Setting window
Dark Light sensor
Power relay
208784
Operation–3 Operation logic:
Auto-light switch ON
Auto-light switch OFF Lighting switch
OFF
1st 2nd position position
Dark OFF
Clearance, tail lamps Head lamps
3-25
1st 2nd position position
Bright OFF
1st 2nd position position
ELECTRICAL SYSTEM
How to Set Controller Set the controller on any of the following occasions: Occasion
Setting
After mast has been changed, or an optional equipment added
Resetting of setting switches
When auto-light system is adjusted
Adjustment of brightness at which light sensor operates
After control valve lift section solenoid has been replaced (or control valve replaced)
Adjustment of maximum lowering speed (when required)
After controller assembly has been replaced
• Resetting of setting switches • Adjustment of maximum lowering speed (when required) • Adjustment of brightness at which light sensor operates (when required)
208785
3-26
ELECTRICAL SYSTEM 1. Setting switches
The controller has a total of 16 setting switches.
NOTE Use a screwdriver to move each switch. The switch is made of resin; be careful not to damage the switch head in setting. 205001
(1) Switch setting pattern (Black dot indicates switch head.)
Setting window
Transmission speed Switch SW 2–2 Spear Switch SW 2–3
Normal OFF
Check ON
1200 bps OFF Normal OFF
Truck model Switch SW 3–1 SW 3–2
9600 bps ON
With OFF
Without ON
Oil pressure sensor Switch SW 2–5
Without OFF
(With) ON
OFF
Seat switch Switch SW 2–4
Spear Switch SW 2–6
Normal OFF
40K OFF OFF
40KL OFF OFF
45K OFF OFF
50K OFF OFF
– ON
– ON
WDT operation Normal mode WDT disabled Switch SW 2–7 OFF ON
1 2 3 4 5 6 7 8
OFF
Mode Switch SW 2–1
1 2 3 4 5 6 7 8
SW2
SW3
OFF
ON
No. of spools Switch SW 3–3 SW 3–4
3V ON OFF
4V OFF ON
– ON ON
Mast model Standard Simplex Duplex SW 3–5 Switch OFF OFF OFF SW 3–6 OFF OFF OFF
Spear Switch SW 3–7 Spear Switch SW 3–8
Program mode User program Boot mode Switch SW 2–8 OFF ON
2V OFF OFF
Normal OFF Normal OFF
Triplex OFF OFF
– ON – ON
208786
(2) Example of setting Truck:
GP40K
40 K
No. of spools: 3V Mast:
4V40A (simplex)
Option:
Speedometer with indicator light
3V
Seat switch
Standard
SW2
SW3 208787
3-27
ELECTRICAL SYSTEM 2. Failures resulting from incorrect setting
(1) Incorrect setting for truck size (4.0 ton, 4.5 ton and 5.0 ton models) Incorrect setting will result in abnormal lowering speed and inching feel. If a setting for a 4.0 ton model is made on a 4.0 ton mode, for example, the lowering speed will be abnormally low. If a setting for a 4.5 ton model is made on a 5.0 ton model, the lowering speed will be abnormally high. (2) Incorrect setting for number of control valve spools (a) If the setting is made for the number of spools greater than is actual, the system indicator light will flicker, and the equipment will not be actuated. (Such a setting is taken as open- or short circuit in the control valve solenoid or in the joysticks.) (b) If the setting is made for the number of spools less than is actual, only the devices equal to the number of the set spools will be actuates. (3) Incorrect setting for mast A setting for a simplex mast will not affect the lowering speed. (4) Incorrect setting for controller check (Be sure to set to OFF.) If it is set to ON, the equipment will not be actuated even if the joysticks are operated.
3. Lowering speed adjusting knob
(1) This knob is for increasing or decreasing the maximum lowering speed. (2) The arrow of the knob has been set to “8”. (3) The lower the figure, the more the lowering speed is decreased. “A” thru “F” mean “10” thru “15”.
NOTE (1) Use a screwdriver to turn the knob. (2) This knob can be turned endlessly in both directions. (3) Be careful not to damage the groove of the knob when putting a screwdriver.
3-28
205004
ELECTRICAL SYSTEM 4. Auto-light sensitivity adjusting knob
(1) This knob is for adjusting the sensitivity level at which the auto-light system turns ON and OFF the head lamps. (2) The knob has been set as shown. (3) The more the knob is turned to the right, the lower will be the sensitivity at which the system turns ON and OFF the head lamps. 205005
NOTE (1) Use a screwdriver to turn the knob. (2) Be careful not to damage the groove of the knob when putting a screwdriver.
5. Working precautions
(1) When installing the controller, position it correctly. Be careful not to turn upside down. (2) When resetting or adjusting the controller on the truck, be sure to turn OFF the starter switch and lighting switch. (3) When removing the rubber cover, check to see if the sealing label was removed before. (If this label shows a sign of removal, ask the user for removal of the label.) (4) Be careful not to damage the rubber cover when it is off the controller. (5) Do not let any foreign matter fall into the controller through setting window.
3-29
205037
ELECTRICAL SYSTEM
Troubleshooting Starter System
Starter will not crank engine
Starter switch Turning off starter switch will not stop engine
Weak or dead battery
Recharge or replace.
Short or open circuit
Repair or replace.
Poor continuity in starter switch
Replace.
Starter or starter relay defective
Replace.
Forward-reverse lever not in neutral position
Move lever to neutral position.
Open or short circuit
Repair or replace.
Engine stop solenoid defective
Replace or readjust.
Control timer defective
Replace.
Open or short circuit
Repair or replace.
Gauge internally defective
Replace.
Gauge unit defective
Replace.
Gauge or gauge unit not of the type called for
Replace.
Loose terminal connection
Repair.
Circuit between gauge and gauge unit grounded
Repair.
Gauge internally defective
Replace.
Open or short circuit
Repair or replace.
Gauge internally defective
Replace.
Gauge unit defective
Replace.
Gauge or gauge unit not of the type called for
Replace.
Loose terminal connection
Retighten.
Circuit between gauge and gauge unit open or short
Repair.
Gauge internally defective
Replace.
Gauge unit defective
Replace.
Circuit between gauge and gauge unit grounded
Repair.
Gauge unit defective
Replace.
Gauge internally defective
Replace.
Gauges Will not indicate at all
Temperature gauges
Will not indicate accurately Will indicate higher than actual temperature
Will not indicate at all
Will not indicate accurately
Fuel gauge
Will indicate “full” regardless of amount of fuel left in tank
Will indicate “empty” regardless of amount of fuel left in tank
3-30
ELECTRICAL SYSTEM
Lighting System
Will not light
Lamps - general
Will light dimly
Head lamps
Will not light
Will not flicker Will not go out Turn signals
Will flicker too slow Will flicker too fast
Other lamps
Weak or dead battery
Recharge or replace.
Fuses blown out
Check and replace.
Open or short circuit
Repair or replace.
Poor grounding
Clean ground spot and re-make connection.
Bulbs burnt out
Replace.
Weak or dead battery
Check and recharge.
Burned contact points in switches
Repair or replace.
Loose terminals
Retighten.
Dirty lenses
Clean.
Waterdrops inside lenses
Dry and replace packings.
Bulbs expired in service life
Replace.
Lighting switch defective
Replace.
Bulbs burnt out
Replace.
Turn signal switch defective
Replace.
Turn signal relay defective
Replace.
Turn signal relay defective
Replace.
Bulbs burnt out
Replace.
Wrong wattage of bulbs
Replace.
Bulbs burnt out
Replace.
Turn signal relay defective
Replace.
Wrong wattage of bulbs
Replace.
Turn signal relay defective
Replace.
Backup lamp switch defective
Correct if improperly installed: replace if internally defective.
Bulbs burnt out
Replace.
Fuse blown out
Check and replace.
Open or short circuit
Repair or replace.
Horn switch defective
Replace.
Horn defective
Replace.
Horn button defective
Repair or replace.
Horn switch defective
Replace.
Horn defective
Replace.
Backup lamps will not light
Alarm Unit
Will not give blast of sound Horn Will give ugly blast of sound
3-31
ELECTRICAL SYSTEM
Battery Drive belt slipping
Readjust.
❋ Alternator Stator coil grounded or open-circuited
Repair or replace.
Rotor coil open
Replace.
Brushes poorly seating on slip rings
Replace brushes if worn. Clean holder and polish slip rings.
Diode ruptured
Replace.
❋ Regulator Tends to run down rapidly
Regulated voltage setting too low
Readjust.
❋ Battery Not enough electrolyte or wrong proportion of acid to water
Refill and check specific gravity.
Battery cell plates deteriorated (forming, possibly internal short-circuit)
Replace.
Terminal connections loose
Clean and retighten.
❋ Wiring Open or loose connection between starter switch and regulator IC terminal
Repair.
Fuse blown, or loosely set in holder
Replace and repair.
Open or loose connection between F terminals of regulator and alternator
Repair.
❋ Wiring
Tends to get overcharged
Regulator IC and F terminals shorted or miswired
Repair.
Poor grounding of regulator F terminal
Repair.
❋ Regulator Pressure coil open-circuited
Replace.
Regulated voltage too high
Readjust.
3-32
ELECTRICAL SYSTEM
FC (Finger-Tip-Control System) 1. Preparatory steps
(1) This system comes into operation when the starter switch is turned to the ON position and the safety switch is turned ON. The finger-tip-control comes into operation after the seat switch has been closed (the operator has been seated) and the engine has been started. (2) Before deciding to replace a blown fuse, check to be sure that the harness connectors in the power line are all in sound condition, free of any sign of short-circuit. (3) The use of the test-use connector (special tool) is prescribed for checking the connector-to-connector (special tool) is prescribed for checking the connectorto-connector lines for continuity and for reading the voltage across two terminals and the ohmic resistance of a line. (4) The controller ’s capabilities include that of selfdiagnosis (for the control system only) function. By this function, any trouble symptom occurring in energized state goes into memory as trouble data. (This memory capability is limited, however, to the latest single case of trouble symptom for one input/output channel: previous symptoms are not memorized, meaning that their chronological order and data are not traceable). The trouble symptom data, limited as above, can be read out through the ground support equipment (GSE). If, however, any of the following steps is taken, the stored data will be erased and lost:
205038
(e) Turning starter switch or safety switch ON and OFF twice in succession. (Turning the switch in this manner is the same thing as performing the cycle of energizing and de-energizing the controller twice in succession.)
(a) Disconnecting battery lead from the battery terminal, positive (+) or negative (–). (b) Uncoupling CN1 or CN4 connector on the console box. (c) Removing the 10-A fuse (6th fuse as counted from top) in the fuse box. (d) Uncoupling CN53 connector on the controller.
3-33
ELECTRICAL SYSTEM
(6) Before starting troubleshooting work, check to be sure that the following conditions are met on the machine side:
(5) When coupling or uncoupling a connector, make sure that the starter switch is OFF. Never try to insert or pull off the connector half forcibly or its pins will suffer damage. When coupling a connector, be sure that the inserted half snaps into its self-locking position. Conditions in the machine Starter switch OFF Safety switch OFF
Engine at standstill Starter switch ON Safety switch ON
Engine running Safety switch ON
Check item
What to check
Remedy
Hydraulic line
Hoses, pipes and connectors for damage and sign of leak.
Repair leaking or damaged parts.
Hydraulic devices
Check control valve and hydraulic cylinders for damage and oil leaks.
Repair damaged or leaking parts, if any.
Electrical connectors and wires
Check connectors for tightness, burns and breakage; check wires for insulator stripping and signs of rubbing.
Repair.
Power source voltage
Check to be sure that voltage is at least 10 V as read across battery’s terminals.
Correct alternator or battery if this voltage is too low.
System check lamp
Check to be sure the lamp goes ON and OFF properly; if not, check its bulb.
Replace lamp bulb if blown.
Auto-light unit
After making sure check light bulb is OK, see if auto-light works properly.
Refer to Case 1 and 2.
LED indicator (red) in the controller
Be sure that red LED go ON and OFF correctly.
Proper functioning of LED indicator is essential to troubleshooting.
Trouble-data reading function of controller
Connect GSE to controller and check its input and output actions.
(Proper functioning of controller is essential to troubleshooting.)
Hydraulic devices
With your hands kept off control levers, see if solenoid valves and hydraulic pump are making any abnormal sound.
Refer to the sections dealing with control valve and hydraulic
pump, respectively. Operate control lever to see if any abnormal sound, indicative of flow throttling, comes from control solenoid valve or from any other solenoid valve. Check to see if unload solenoid valve operates properly, in response to a lever being moved. Work attachments
Check each work attachment for the following: (a) Does it work properly? (b) Does it “inch” properly? (c) Does mast go down with proper speed?
3-34
(Proper function of solenoid valves is essential to troubleshooting.)
Refer to Case 3. Refer to Case 4.
Refer to Case 5.
ELECTRICAL SYSTEM 2. Connecting the GSE to the Controller
(1) Remove the rubber cap.
208788
(2) First, turn ON the starter switch. After this, select the lift menu (by referring to the GSE operation manual).
NOTE Before plugging in or unplugging the GSE cable, be sure to have the starter switch turned OFF.
3-35
ELECTRICAL SYSTEM 3. Troubleshooting Cases as Examples
(1) Explanatory notes and reminders (a) In the text and diagrams to follow, electrical connectors are abbreviated CN. An individual CN will be identified by a number suffix (used in the electrical wiring and connecting diagrams). (b) In the flowchart diagrams, the numerical notation in the box, , is a circuit number. The terminals of a connector too will be identified by circuit numbers. As to the configuration of terminals in each connector, refer to the wiring diagram. (c) The wiring diagrams show the connector’s terminal configuration on its male side: remember, the configuration on the female side is a mirror image of the male-side configuration. (d) In the trouble cases cited hereunder, “check the connector coupling” means “uncouple and then couple the connector, inserting the connector, inserting the connector half all the way to selflocking position.” (e) In the trouble cases cited, “continuity check” will be directed for some harnesses. This direction applies also to “check the connector coupling”: when checking a connector as in (d), above, be sure to check the connector for circuit continuity immediately after coupling it.
Component
(f) When reading a voltage with a circuit tester, be sure to discriminate polarities, (+) and (–), so that the tester will not suffer internal damage.
Trouble symptom
Control levers
Short-circuit
Solenoid valves
Short-circuit, oil leakage
NOTE For the method of deleting the data stored in the controller, refer to (a) thru (e), 1. (4).
(g) Trouble data stored in the controller, as explained in 1. (4), can be read out by the GSE. Such a read-out is the “data on trouble as was” and must not be interpreted as data on the trouble confirmed to exist. To illustrate this point, assume that the data are currently displayed in the form shown on the right and that the indicated faulty conditions have already been corrected by repair. In this case, the work attachment in question remains inoperative. Thus, it is important that, each time a detected malcondition is corrected and eliminated, the trouble data be changed promptly to reflect the correction effected. 3-36
ELECTRICAL SYSTEM
(h) Not withstanding what is said in (g), above, the “data on past trouble,” as read into the GSE from the controller, can be useful information in checking for such malconditions (like an open due to loose contact in a circuit) as may not show up later at the time of performing a troubleshooting work. The diagram, below, illustrates and example of precarious type of malcondition:
The malcondition on the left, detected at the time of trouble occurrence, will go into the data as “opencircuit” if it happens to present an open. Trouble symptom data
Open-circuit
Supposing that, as you start the troubleshooting work with the GSE, the near-open fault happens to be in a precariously closed condition: then, the GSE will indicate the circuit of the device in question as normal whereas the data held in the controller reads “open-circuit” for that device. Trouble symptom data
Device
Past
Open-circuit
Now
Normal 208790
3-37
Clearance lamp
Head lamp
Tail lamp
Auto-light system schematic
Light sensor
B
3-38 10 A
Starter switch
Lighting switch
Power relay
20 A Auto-light switch OFF ON
P H T
Console box
Instrument panel lamp
184
201
173
Battery
177
Safety switch
169
Control (joystick) box
ON or OFF signal
Power supply
Setting window
Controller
Bright
208791
Dark
169 177 173 184
182 183 186 187
Turn-On
Auto-light sensitivity adjusting knob
NOTE: Circuit Nos. are indicated by small-character numbers.
ELECTRICAL SYSTEM
(2) Auto-light System Troubleshooting
ELECTRICAL SYSTEM
(a) Case 1: Head lamps will not go ON in darkness. Troubleshooting procedure
Is the LED (red) ON in the controller?
No
Refer to Case 7: “Controller’s LED (red) will not go ON.”
Yes
Set the sensitivity to make the lamps turn ON at the desired degree of darkness.
Yes
Check CN51, CN52 and CN53 for continuity. If these connectors are OK, it means that the controller is in faulty condition and needs to be replaced.
No
Check the circuits of power relay and auto-light switch (in the console box) for continuity. As necessary, repair or replace.
Yes Do the head lamps go ON when the sensitivity is re-adjusted? No Do the head lamps go ON when circuit 173 (CN51) is grounded (shorted to the ground)? (Does this shorting cause the power relay to trip ?) No Have circuit 184 shorted to circuit 201 at the male side of CN4. Then, ground circuit 173 : will this turn ON the head lamps? Yes Check harness B for continuity and repair faulty part or line, if any.
3-39
ELECTRICAL SYSTEM
(b) Case 2: Head lamps will not go OFF when bright. Troubleshooting procedure
Is the LED (red) ON in the controller?
No
Refer to Case7: “Controller’s LED (red) will not go ON.”
Yes
Set the sensitivity so that the lamps will go OFF at the desired degree of darkness.
Yes
Is the resistance through CN52 (between circuits 177 and 169 ) less than 20 kilohms?
Yes Do the head lamps go OFF when the sensitivity is re-adjusted? No Do the head lamps go OFF when CN51 is disconnected? No
No Check the light sensor circuit for continuity and repair or replace.
Do the head lamps go OFF when CN4 is disconnected? No
Yes
Yes
Check CN51, CN52 and CN53. If these connectors are OK, it means the controller is in faulty condition and needs to be replaced.
Check power relay and auto-light switch (in the console box) for shortcircuit, and repair or replace.
See if circuit 173 of harness B is shorted to chassis or to ground circuit and, if so, repair.
3-40
Lift cylinder
3-41 Hydraulic pump
Unload solenoid
10 A
System indicator light Starter switch
Console box
Control system schematic
Control valve unit
Seat switch
Flow control signal
Proportioning solenoid
Control Lowering speed lever selector switch Safty (joystick) switch
Control (joystick) box
Setting window
Controller
On or OFF signal
ON or OFF signal Lever position signal
Power supply
208792
ELECTRICAL SYSTEM
(3) Control System Troubleshooting
ELECTRICAL SYSTEM
(a) Case 3: No motion of hydraulic cylinders. Troubleshooting procedure
Is the system check lamp ON or OFF?
OFF
Yes Move the control lever: does throttling The control valve noise or any other abnormal noise come Yes is internally in from the control valve? (Does the faulty condition. unload solenoid operate?)
Stays ON or flickers Re-set.
No
Is the controller set to match the machine specification?
Yes Connect the GSE to the controller and read out the current trouble data. Use GSE to monitor trouble.
Flicker
No Is the controller’s LED (red) ON or OFF? Stays ON
Are all levers normal?
Are all input trouble data (on a lever), as read by the GSE, normal? Yes Are all output trouble data (on the sensor), as read, normal? Yes Are all output trouble data (standard), as read, normal? Yes Are all output trouble data (on the work attachment), as read, normal? (This does not apply to the two-element control valve unit.)
No Turn OFF safety switch.
Is safety switch off ?
Refer to case 8.
Stays OFF Refer to case 7.
No
Check the harness and connectors of the lever in question for continuity. If open-circuit condition is noted, replace the lever assembly.
No
Check for continuity the harness and connectors of the component in question. If open-circuit is noted, replace the component.
No
No
Check for continuity the harness and connectors of the solenoid in question. If open-circuit is noted, replace the solenoid. (Refer to the section on solenoid control valves.)
Yes Read the past trouble data into the GSE.
No
Check for continuity the harness and connectors of the lever in question. If short-circuit is noted, replace the lever assembly.
Yes Are all input trouble data (on the sensor), as read, normal?
No
Check for continuity the harness and connectors of the component in question. If short-circuit is noted, replace the component.
Yes Are all output trouble data (standard), as read, normal?
No
Yes Are all output trouble data (on the attachment), as read, normal?
No
Are all input trouble data (on the lever), as read, normal?
Check for continuity the harness and connectors of the solenoid in question and, if short-circuit is noted, replace the solenoid. (Refer to the section on solenoid control valves.)
Yes To deal with an internal malcondition of any solenoid control valve, refer to the section on solenoid control valves. If necessary, contact the manufacturer. 3-42
ELECTRICAL SYSTEM
(b) Case 4 : No inching motion of hydraulic cylinders Troubleshooting procedure
Does abnormal noise issue out when the mast is operated with normal working speed?
Yes
Check for hitching, sticking and rattling. Repair to smoothen the movements.
No Is the controller set to match the machine specifications?
No
Re-set.
Yes Connect the GSE to the controller and read “Input condition� into the GSE. Check to be sure that the data, as read, indicate the control lever 76 HEX to 8A HEX.
Move the control levers slowly back and forth and check that indication varies continuously between 0 and 100%. Test the control lever, as above, twice or thrice, to be sure there is no jump or dip in the rising indication.
No
The cause is a malcondition within the solenoid control valve. If necessary, contact the manufacturer.
Yes Check the harness and connectors of the lever in question for continuity. If discontinuity is noted, replace the lever assembly.
3-43
ELECTRICAL SYSTEM
(c) Case 5: The maximum lowering speed of the mast is too high (or too low). Troubleshooting procedure
Is the controller set to match the machine specifications?
No
Re-set.
Yes Is the adjusting knob (for the max. lowering speed of the mast) effective in adjusting this speed of the mast?
Yes
(End)
No Connect the GSE to the controller and read out “Input condition� into the GSE.
Does the indication on the output monitor screen vary between 0 and 100% as the lever angle is changed?
No
The lever is faulty or there is something wrong with the harness.
No
The controller is faulty or there is something wrong with the harness.
Yes Are there changes in current of the order of 0.4 to 0.9 A? Yes The solenoid valve is faulty or there is something wrong with the harness.
3-44
ELECTRICAL SYSTEM
(d) Case 6: During the lowering action of a lift cylinder differ in actuating speed. Troubleshooting procedure
Is the controller set to match the machine specifications?
No
Re-set.
Yes Connect the GSE to the controller and read out “Input state (2)� into the GSE.
Operate the mast: see if the lift cylinder indication make an ONto-OFF change when 2nd cylinder starts rising from its fully retracted position. Will the change occur? (Test twice or thrice to be sure of the lift cylinder action.)
Yes
Contact the manufacture.
No Check for continuity the harness and connectors of the lift cylinder circuit. As necessary, replace the lift cylinder.
3-45
ELECTRICAL SYSTEM
(e) Case 7: Controller’s LED (red) will not go ON. Troubleshooting procedure
Check the fuse. Is the fuse OK or NG?
NG
Replace the fuse, and check the harnesses for open or short.
No
Is the voltage between circuit 201 on the male side of CN4 and ground at least 10 volts?
OK Read the voltage between ground and circuits 182 and 183 (CN53). Is the reading at least 10 volts? (Is power being supplied to the controller?)
Yes
Yes
Check the power supply circuit (inside the console box) for continuity. Repair and correct an open if any.
Is there continuity between circuits 186 and 187 and the ground? Yes
No
No Is there continuity between circuit 201 (on the female side of CN4) and circuits 182 and 183 (at CN53)?
Check to be sure that CN51, CN52 and CN53 are all in sound condition. If the trouble persists, replace the controller.
Check harness B for continuity. Repair and correct an open, if any.
Yes
No
While making sure that each connector is coupled up tight, check to see if the LED turns ON; if not, contact the manufacturer. Yes
Is there continuity between circuits 183 and 201 at the male side of CN54? No Check the safety switch and engine hood harness for open-circuit. Repair and correct an open if any, or replace the switch as necessary.
3-46
ELECTRICAL SYSTEM
(f) Case 8: Controller’s LED (red) will remain ON. Troubleshooting procedure
Does the LED remain OFF, indicating the power supply is faulty?
No
Is the voltage between circuit 201 on the male side of CN4 and ground at least 10 volts? Yes
No Check the power supply circuit (inside the console box) for continuity. Repair and correct an open if any.
Is the resistance between circuit 201 (on the female side of CN4) and circuits 182 and 183 (at CN53) less than 0.1 ohm? Yes
No
While making sure that each connector is coupled up tight, check to see if the LED turns ON; if not, contact the manufacturer. Check harness B for continuity. Repair and correct an open, if any.
Yes
If the resistance between circuits 183 and 201 on the male side of CN54 less than 0.05 ohm? No Check the safety switch and engine hood harness for open-circuit. Repair and correct an open if any, or replace the switch as necessary.
If the LED remains ON; Are the DIP switches correctly set? Is the SW2-8 set OFF?
No Re-set.
Yes Replace the controller.
3-47
ELECTRICAL SYSTEM 4. How to Move the Mast in an Emergency
If the truck fails while at work and, you then have to drive it (if the engine is OK) or tow it to some distant place or to the repair shop, do the following steps: (1) Mast lowering (a) Loosen lock nut 1 on the lift section of the contrl valve. (b) Using an Allen wrench, slowly loosen screw 2. This causes the mast to go down by gravity: tighten screw 2 and the mast will stop.
CAUTION Before doing these steps, be sure that there is no one standing under the mast. 205008
(c) Tighten lock nut 1.
CAUTION Leaving nut 1 loose is dangeraous: the mast might suddenly start going down by itself.
(2) Lifting, tilting or auxiliary function
CAUTION Steps (a) thru (i), below, are dangerous for the following actions:
Action
Remarks
Lowering the mast
Mast will move in free-falling manner.
Dumping the hinged fork (or bucket) Dumping the dump fork (or bucket)
Jerky dumping action. (The load will fall off.)
Releasing clamped load
The load will fall.
3-48
ELECTRICAL SYSTEM
(a) Remove the unload solenoid connector of the control valve. Remove the proportional solenoid connector on that end of the control valve which is for the action you need. (b) Using a circuit tester, check the two solenoids (unload solenoid and proportional solenoid) for short or open. The faulted solenoid, if any, must be replaced by a new one at this time. (If the proportional solenoid, from which you pulled off the connector half, is faulty, you may replace it temporarily by another solenoid in place on the control valve.)
Proportioning solenoid connectors Tilt forward Mast down
Attachment 1 Attachment 2
Operates when lever is pushed.
From bottom to top
Unload solenoid connector Mast up Tilt backward
Operates when lever is pushed. Attachemnt 2 Attachment 1
Proportioning solenoid connectors
208793
(c) To the two connector halves, from which the female halves were disconnected in step (a), above, couple the female halves of the emergency-use harness (special tool), as shown. Special tool needed Emergency-use harness
91105 - 00400
(d) Connect the “black� alligator clip (of the other end of the harness) to the negative (–) terminal of the battery: have the other (red) alligator clip put on the harness, as shown. (e) Start up the engine.
3-49
205010
ELECTRICAL SYSTEM
(f) Hold the engine in idling condition. Look around the machine to be sure no one stands near the truck. Now, take off the “red” alligator clip and touch the battery’s positive (+) terminal with it: as you do so, the action you need (corresponding to that of the proportional solenoid now connected to the battery) will start: the action will stop as you remove the “red” clip from the terminal.
CAUTION (1) Do not keep touching the battery terminal (+) with the “red” alligator clip, or the solenoid will get burned. Touch intermittently. (2) You may raise the engine speed while intermittently energizing the solenoid but do so cautiously, keeping an eye on the action in progress.
(g) If the desired action does not occur in step (f), above, it means that there is some malcondition inside the control valve. (h) Stop the engine, and remove the emergency-use harness. (i) Re-couple the connectors of unload solenoid and proportioning solenoid.
3-50
205011
ELECTRICAL SYSTEM
(3) How to cope with a failed (open-circuited) seat switch Your troubleshooting investigation might reveal that the seat switch is open-circuited or otherwise faulted and will not function. In such a case, you can create a temporary circuit continuity through the seat switch line. The method is explained in this illustration. The seat switch is a security part. Be sure to replace it by a new one as soon as possible.
Two connectors are in the seat switch line at the indicated location. Open these connectors, and couple up the male and female connector halves to form a circuit bypassing the seat switch.
208794
CAUTION Illustrated above is a first-aid method permissible only in an emergency situation. Be sure to restore the seat switch line to the normal hookup after replacing the failed switch.
3-51
ELECTRICAL SYSTEM 5. How to Clean Harness Connectors and System Components
(1) Open-circuit trouble is often due to the harness connectors and components in dirty condition: dust, together with greasy matter, forms grime which, in time, penetrates electrical connections, resulting in loose metal-to-metal contact or, for worse, electrical separation of surfaces in contact. For this reason, it is essential that the connectors and components be cleaned at each periodic inspection and at the time of servicing the machine. Instead of a commonly used solvent, use electronic parts cleaner (in the manner illustrated on the right). Electronic parts cleaner
208795
ThreeBond 29B
NOTE The cleaner liquid is volatile. All you have to do is just give a strong spray to wash off grime. No need to wipe off the sprayed liquid.
(2) After checking the connector for continuity, wash it as above. Then, uncouple the connector and spray contact surface activator onto contact surfaces. Now, install and remove the connector several times to wet the surfaces thoroughly with the activator liquid. After coupling up the connector so sprayed on, check to be sure that it is in locked state.
Contact surfaces activator
ThreeBond 2501S (aerosol)
NOTE Do not spray too much: bear in mind that this spray liquid reacts with some resins (plastic materials).
205047
3-52
ELECTRICAL SYSTEM 6. Troubleshooting Guide for Solenoid Control Valves
Trouble symptoms
Possible causes
The pump discharge pressure will not build up
Remedies
1. Unload solenoid not working 2. Sticky plunger in proportioning solenoid of reducing valve, or sticky shuttle in reducing valve 3. Open in lead wire or in solenoid coil 4. Input current to solenoid too small 5. Unload valve stuck open 6. Spool stuck in flow-divider valve
Sticky spool
Sticky plunger in proportioning solenoid of reducing valve, or sticky shuttle in reducing valve.
Disassemble and clean by washing. Replace solenoid as necessary. Disassemble and clean by washing. If the plunger is sticky, replace the solenoid. Repair or replace. Check to make sure that solenoid is drawing specified maximum input current. • Check unload solenoid for action. • Check unload valve for action. Disassemble and clean by washing. Disassemble and clean by washing. If plunger is sticky, replace solenoid.
7. Troubles Conceivable for Each Component LED ON-OFF pattern
Threshold
Normal
A
–
Control levers are not in their neutral positions when power supply is turned on.
D
128 ± 10 (A/D value)
Turn off corresponding Flash solenoids’ outputs.
Input level is higher than lever maximum position level.
B
245 to 255 (A/D value)
Turn off corresponding ON solenoids’ outputs.
Short circuit
Input level is lower than lever minimum position level.
B
0 to 10 (A/D value)
Turn off corresponding ON solenoids’ outputs.
Open circuit
Abnormal if current is 0 when solenoid output is ON.
C
120 mA or lower
Turn off abnormal solenoid’s output.
ON
Short circuit
Abnormal if solenoid output current level is higher than threshold level.
C
2.4 A or higher
Turn off abnormal solenoid’s output.
ON
Leakage
Abnormal current is detected during emergency operation.
C
140 mA or higher
Turn off all solenoids’ ON outputs.
4 Seat switch
Open circuit
Check I/O levels. Abnormal if signal stays OFF.
E
OFF for 15 seconds or longer
Turn off all solenoids’ Flash outputs.
5 CPU
Abnormality
(CPU does not run.) (WDT causes CPU reset.)
F
6 Battery voltage
Voltage drop, Voltage is out of specification overvoltage
C
Lower than 10 V; Turn off all solenoids’ ON higher than 32 V outputs.
7 Setting switch
Check mode
G
S1 ON
1
Component
Trouble
–
–
2 Control levers Not in neutral (1) Lift lever (2) Tilt lever (3) Attachment 1 lever Open circuit (4) Attachment 2 lever
3 Solenoids (1) Lift (2) Tilt (3) Attachment 1 (4) Attachment 2
Condition
Setting of SW 2 (DIP switch)
3-53
–
Action No action
System check lamp OFF
Turn off all solenoids’ Irregular outputs.
Start check mode operation (solenoid operation)
(OFF)
Thank you very much for your reading. Please Click Here Then Get More Information.