Tomorrow's Tech

■ BRAKE-RELATED COMEBACKS ■ POWER STROKE PROBLEMS ■ 'PLUGGING AWAY' IN IGNITION DIAGNOSTICS

February 2013 TomorrowsTechnician.com

CONTENTS IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII

UNDER THE HOOD 14 Plugging Away at Ignition Diagnostics Intermittent ignition coil failures can be tough to diagnose. Babcox technical editor and former instructor Gary Goms discusses the different configurations and breaks down the variety of options for testing ignition coils and ignition systems.

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UNDERCOVER 24 Stopping Brake-Related Comebacks Nothing is worse than a customer returning to your shop after a brake job complaining of a noise or performance issue. Comebacks can be frustrating because they negatively impact a shop’s productivity and reputation. The following are 10 tips that can help you more efficiently and effectively solve a brake comeback due to noise.

ENGINE SERIES 34 Problems That Plague the Power Stroke Diesel engine specialist Bob McDonald investigates the problems and complaints regarding the 6.0L Power Stroke and provides aftermarket fixes that will get owners of the trucks powered with this diesel engine back on the road.

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Report Card: Mercedes-Benz’s Ener-G-Force Concept

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The Real World: Future Technology Meets Future Technicians

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Service Advisor: 20 Tips for TPMS Service

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Bulletin Board

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Crossword Puzzle

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Tomorrow’s Technician (ISSN 1539-9532) (February 2013, Volume 12, Issue 1): Published eight times a year by Babcox Media, 3550 Embassy Parkway, Akron, OH 44333 U.S.A. Complimentary subscriptions are available to qualified students and educators located at NATEF-certified automotive training institutions. Paid subscriptions are available for all others. Contact us at (330) 670-1234 to speak to a subscription services representative or FAX us at (330) 670-5335.

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Report Card

While off-road vehicles aren’t normally associated with being “green,” the Mercedes-Benz EnerG-Force electric vehicle concept would have no trouble existing in such a rough environment.

As an environmentally friendly SUV, the Ener-G-Force, which Mercedes-Benz presented at the LA Auto Show late last year, sprouted from a design study concept of a highway patrol vehicle for the year 2025.

“The Ener-G-Force is the vision of an off-roader that, while reflecting tomorrow’s adventures, also invokes the genes of the Mercedes-Benz off-road icon, the G-Class,” said Gorden Wagener, Director of Design at Mercedes-

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Benz. “Modern and cool, it could also be a clue about a new beginning for the off-road design idiom of Mercedes-Benz.”

The Ener-G-Force is unmistakably inspired by the G-Class, which has long been considered an automotive icon. However, it presents a radical reinterpretation of this classic that looks far into the future. Important genes such as proportions and design elements were completely redesigned and updated in a clean concept for beyond tomorrow.

The Ener-G-Force stores recycled water in tanks on the roof, and transfers it to the “hydro-tech converter,” where natural and renewable resources are converted into hydrogen for operating the fuel cells. The storage units for the electricity generated in this process are housed easily accessible in the striking side skirts.

The Ener-G-Force emits nothing but water, has an operating range of about 500 miles and as a result, truly is a green car.

Four wheel-hub motors, whose output for each individual wheel is adapted precisely to the respective terrain by highperformance electronics, provide the pulling power.

A “Terra-Scan” 360-degree

February 2013 | TomorrowsTechnician.com

topography scanner on the roof permanently scans the surroundings and uses the results to adjust the spring and damping rates as well as other suspension parameters for maximum traction on the respective surface, regardless of whether it is on- or off-road.

For now, the Ener-G-Force is pure science fiction. But, the design could represent a clear step forward for the automaker in the future. And, the SUV concept also plays on the utility factor in an entirely new way. For example, the distinctive feature in the rear is a slightly off-center pull-out compartment whose cover occupies the traditional location of the spare wheel cover of the classic G-Class. This pull-out tool box can hold a wide variety of equipment, supplies or even campfire provisions that are quickly within reach without having to open the entire tailgate. Which could come in handy on those offroad nights. ■

Real World

FUTURE TECHNOLOGY’S IMPACT ON FUTURE TECHNICIANS

By Ed Sunkin, editor

T

he auto industry won’t be producing vehicles in the near future that encompass the options of the flying “Spinner” cars portrayed in 1982’s Blade Runner, however, the reality is that we will soon be seeing something more like the “Johnny Cabs” that hailed from the 1990’s film Total Recall.

In March of last year, the Nevada Department of Motor Vehicles issued a license for a self-driven car, and in late September 2012, California’s Gov. Jerry Brown, at a ceremony at Google’s headquarters in Mountain View, signed into law a bill that his state’s Department of Motor Vehicles is to write regulations covering robot cars by January 2015. The law also has paved the road to allow autonomous vehicles to operate on California roads.

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“I expect that self-driving cars are going to be far safer than human-driven cars,” said Google cofounder Sergey Brin. “Self-driving cars do not run red lights.”

AUTONOMOUS AUTOS There is a lot of speculation on how these driverless vehicles will impact the automotive service industry.

For one thing, it’s going to take technicians like you to become even more skilled in computers and electronics to service these vehicle systems. Bob Lutz, former GM vice chairman and idea man behind the Chevy Volt, said recently that he expects mass-produced driverless vehicles on the roads within 20 years and that the technology to operate such vehicles is already available. Lutz cited

“smart systems” like start-stop service or maintenance even without technology, lane departure warning a passenger. Let’s just hope the systems, adaptive cruise control and “smart car” doesn’t forget the credit GPS guidance — designs currently card to pay for the work. used in some of today’s high-end MORE DIESELS HEADING vehicles — will be combined by DOWN THE PIPELINE engineers to produce the hands-free You also can bet on seeing more cars. diesels in your workplace — whether Together, these advancements are it’s a dealership or independent designed to keep the vehicle in its repair shop. When the Obama lane and at a safe distance from the Administration announced tougher car in front of it. The car will also fuel economy standards for vehicles apply the brakes to avoid a collision, last August, much of the focus sureven when a car driving 30 miles rounded gasoline-powered cars and slower suddenly pulls in front of it. trucks.

Lutz thinks this is a great idea, since “cars don’t smoke pot or drink,” and thereby the nation will see a reduction in driverimpaired accidents.

However, the vehicles could be bad news for collision shops, as fewer accidents transforms into less work for collision shops.

A Chevy Cruze diesel will launch this year Insurance costs also could Daimler will soon be sharing in the U.S. with a fuel usage range close decline. expenses with Ford and While the expected to 50 mpg. safety improvements are Renault-Nissan for a But for Allen Schaeffer, executive mass-produced hydrogen-fueled beneficial, the aftermarket may see director for the Diesel Technology more miles per vehicle increase, as electric vehicle.

Forum (www.dieselforum.org), the technology will allow more peothese requirements will increase the ple such as the elderly and those growing popularity of diesel vehicles who do not like to drive in traffic the in the U.S., something he is excited opportunity for more travel. about.

Vehicles also could be pro“Because clean diesel autos are grammed to arrive at your shop for 20% to 40% more efficient than gasoline vehicles, diesel will be a major player in the nation’s effort to achieve the new mileage standards.”

Schaeffer said this is good news to manufacturers and suppliers of clean diesel technology who will “play an expanded role in improving fuel economy of the fleet needed to achieve the 54.5 mpg level by 2025 as mandated by the new greenhouse gas and fuel efficiency standards.”

The result will be an increase in diesel service opportunities. It may be a good idea to look toward becoming ASE-certified in diesel engine diagnostics.

Google reported that its experimental autonomous Prius has In fact, in the first six months of driven more than 300,000 miles without an accident.

Photo credit: Steve Jurvetson

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2012, clean diesel automobile sales in the U.S. increased 27.5%, according to sales information compiled by HybridCars.com and Baum and Associates.

While clean diesel auto and light truck sales total only about 3% of the total U.S. passenger car and small truck market, the steady double-digit monthly sales increases show a definite trend of interest in diesels.

A recent Pike Research study forecasts that sales of these lightduty clean diesel vehicles will increase from 282,000 vehicles i-n 2012 to 928,000 by 2018.

While current Clean Diesel vehicles include pick-up trucks from the domestic automakers, diesel cars from the European manufacturers include the Audi A3 and Q7 TDI models, BMW 335D and X5 xDrive35d, Mercedes-Benz E350, ML350, GL350 and R350 BlueTEC diesels, and VW Beetle, Golf, Jetta, Passat and Touareg TDI models.

New vehicles with diesel engines introduced into the U.S. market in the next two years include Chrysler’s Jeep Grand Cherokee Ecodiesel in 2014, along with a new version of the discontinued Dakota pickup that will include a diesel. Ford will offer a new diesel Transit full-size commercial van this year, as will GM with a Cadillac ATS diesel and a diesel version of the Chevrolet Cruze. Mazda will become the only Asian car manufacturer to sell diesel cars in the U.S. when it introduces its SKYACTIV-D 2.2L clean diesel engine next year.

SELLING THE FUEL-CELL CONCEPT Over the past few years, the automotive industry has focused on plugin electric vehicles and various gasoline- and diesel-electric hybrid designs; but now, electric fuel-cell vehicles are returning to the spotlight.

Recently, a collaborative partnership approach between Daimler, Ford and Renault-Nissan was announced in an effort to begin mass producing hydrogen-fueled fuel-cell electric vehicles (FCEVs) in the next four years.

The benefit of these zero-emissions vehicles is their potential to reduce pollution and cut down on the world’s reliance on oil for transportation. However, the drawback over the years has been cost. The automakers believe that combining resources could help alleviate the largest challenge for such vehicles — a fueling infrastructure.

Powered by electricity generated from hydrogen and oxygen, FCEVs emit only water while driving. FCEVs are considered complementary to today’s battery-electric vehicles and will help expand the range of zeroemission transportation options available to consumers.

While each vehicle is expected to use the same electric core design and components, models will still be unique to each automaker. This allows manufacturers to offer different body styles, cabin designs and branding to buyers.

But the concept of sharing fuel-cell core platforms and components would also be helpful for repair shops in the future, as diagnostic tools used to service these vehicles could also be shared, instead of technicians purchasing tooling for individual manufacturers.

While FCEV technology has been in the development stage for a number of automakers including General Motors and Toyota since the late 1990s, the implementation of a consumer vehicle hasn’t taken off due to the high costs of development, design and patents. Hydrogen fueling stations have been introduced in the U.S., but are mainly concentrated around FCEV testing areas out West.

Under the alliance agreement from Daimler, Ford and Nissan, each company will invest equally in the technology. The cars could be available as early as 2017.

According to a release from the alliance, “The collaboration sends a clear signal to suppliers, policymakers and the industry to encourage further development of hydrogen refueling stations and other infrastructure necessary to allow the vehicles to be mass-marketed.” ■ TomorrowsTechnician.com 11

Under the Hood

Adapted from Gary Goms’ article in

‘PLUGGING’ AWAY

D

uring the past century, ignition coil configurations have evolved from oil-filled canister to epoxy-filled to e-core to waste spark and to the most modern coil-on-plug or “pencil” coils. Whatever the configuration, an ignition coil creates a spark by transforming amperage into volts.

To illustrate, an oil-filled ignition coil might require about 4 amperes of current at 12 volts to produce 20-30 kilovolts (kV), while a modern e-core or coil-on-plug configuration might require about 7 amperes of current at 12 volts to produce 30-60 kV of high-intensity spark. Keep in mind that, because many different factors affect the voltage multiplication process, the ultimate voltage output will vary according to design and operating conditions.

See Photo 1.

Whatever the configuration, an ignition coil has three parts: a primary circuit, a secondary circuit and a soft-iron core. A magnetic field is created around the soft-iron core when an electric current flows through the primary circuit or winding. When the current flowing through a few hundreds of turns of primary winding is interrupted, the resulting magnetic field collapses into many thousands of turns in the secondary winding. By “cutting” the magnetic field many thousands of times, the secondary winding multiplies or transforms low battery voltage into the voltages needed to create an ignition spark.

Keep in mind that the actual output voltage of the coil depends upon the air/fuel (A/F) ratio and the running compression of the engine at the spark plug gap. In general, lean A/F ratios and high cylinder pressures tend to increase the voltage requirement at the spark plug.

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PRIMARY NOTES An ignition coil primary circuit includes the battery voltage or B+ terminal attached to a 12-volt current source and a ground or B- terminal attached to a power transistor that controls primary current flow. To create a spark, the power transistor is commanded by the powertrain control module (PCM) to form a magnetic field in the coil by grounding the primary circuit. Coil “saturation” occurs as the magnetic field is formed. The PCM then commands the power transistor to interrupt the primary circuit and collapse the magnetic field, which then creates an ignition spark.

The primary circuit on-time is generally referred to as “dwell angle” on distributor ignitions and “duty cycle” on distributorless ignitions. Dwell angle and duty cycle begin when the primary circuit is grounded and ends when the primary circuit is interrupted.

See Photo 2.

COIL KILLERS Ignition coils are very rugged and reliable, but can fail for a variety of reasons. Top killers of Ignition coils are: 1. Heat which can damage a coil’s insulation.

2. Vibration which can damage the coil's windings and cause shorts or opens in the primary or secondary windings.

3. Voltage overload caused by bad spark plugs or plug wires.

AT IGNITION DIAGNOSTICS

Photo 1: Most technicians are familiar with oil-filled (center), epoxy-filled (left), e-core, waste-spark and pencil-type (right) ignition coils.

While some import electronic ignitions mount a power transistor directly onto the coil, the power transistor in most ignitions is incorporated into a separate ignition control module (ICM). To further simplify ignition hardware, most modern configurations incorporate the power transistor or primary ignition “driver” into the PCM. Because most modern ignition systems are capable of producing secondary voltages up to 60,000 volts or 60 kV, the ignition systems are programmed to reduce coil operating temperatures by reducing the duty cycle or “on-time” at idle speeds, and also by increasing the duty cycle at high engine speeds. This feature increases coil life by reducing the coil’s internal operating temperature.

SECONDARY CIRCUIT The secondary circuit of a distributor ignition system is

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comprised of the secondary ignition coil windings, distributor cap, distributor rotor, spark plug cable and spark plug.

Distributorless systems have eliminated the distributor cap and rotor, but have retained the spark plug cable.

Toyota, among others, often utilizes a “hybrid� waste-spark ignition on V-block engines. In this configuration, the ignition coils on

one cylinder bank are mounted directly onto the spark plugs, and the spark plugs on the opposing bank are connected to the coils by ignition cables. In contrast, a dedicated COP ignition system mounts the coil directly onto the spark plug. Obviously, the COP system has the least number of components to fail.

See Photo 3.

Photo 2: The coil driver saturates the primary circuit by pulling the circuit to ground.

Photo 3: When the coil driver interrupts the primary circuit, the coil’s magnetic field collapses, producing a high-voltage spark.

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DIAGNOSING IGNITION COILS Right off the top, I want to emphasize that intermittent ignition coil failures are tough to diagnose because ignition coil windings tend to be very sensitive to engine heat.

Remember that heat increases primary and secondary circuit resistance and that both windings expand with heat. This is why an ignition coil might pass all shop tests, but will still fail when subjected to high operating temperatures and maximum loads.

I’m also the first to say that a variety of opinions exist about how to test ignition coils and ignition systems. The most basic method is measuring a coil’s primary and secondary resistance. If a coil doesn’t meet the manufacturer’s specifications, it should be considered defective. But, meeting primary and secondary resistance specifications on the bench is no guarantee that the coil will perform correctly under extreme heat and load.

The next method is a process of elimination that tests the coil driver. Because cranking dwell time on modern systems can be 7° or less, never use a conventional test light for testing. Instead, use a DVOM to measure duty cycle or to measure for the presence of voltage drop at coil B as the driver switches the coil on to off. If the coil driver works, the coil is presumably defective.

The most conventional method for testing coils is to observe how well the spark jumps across an air gap while cranking the engine.

This method has several problems because cranking the engine with a defective or poorly charged battery simply won’t deliver the primary voltage needed to properly saturate the coil’s primary windings. The battery must also

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maintain at least 10 volts at the PCM to keep the PCM fully operational.

Because the testing at an air gap must be constant and measurable, many techs use spark testers that create approximately a 0.250” gap for older ignitions and a 0.500” spark gap for later, high-voltage ignitions. The color of the spark often has more to do with atmospheric contamination than it does with the quality of the spark. In some cases, a really “hot” spark is nearly invisible to the eye. Last, any spark generally appears weak when seen in direct sunlight, which can confuse the diagnosis.

Ignition scope analysis can be equally confusing because, during the days of contact point ignitions, technicians compared their scope captures with an “ideal” waveform pattern that contained a specific number of primary and secondary oscillations in the coil waveform. But, when transistors are used to interrupt the primary circuit, the primary and secondary waveforms can vary dramatically from the “ideal” waveforms pictured in many automotive texts.

As the epoxy-filled and external iron core configurations (e-core) were popularly introduced in the early 1980s, we saw the primary and secondary waveform oscillations nearly disappear. With a waste-spark secondary ignition coil operating on both positive and negative grounds, we also see quite a difference between compression and exhaust waveforms.

Because most COP designs lack accessibility, secondary waveform analysis has become difficult to execute in most applications.

The type of scope equipment being used is also critical for an accurate waveform analysis. Most automotive lab scopes won’t tolerate the high voltage “kick” encountered during primary and secondary circuit test-

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Photo 4: This “flat-top” waveform indicates that this coil is current-limited at about six amperes. ing. Others lack the resolution or definition needed for accurate coil waveform analysis. On the other hand, most will display a secondary waveform by using an inductive adapter attached to the spark plug cable or to the coil top on COP applications.

Most advanced technicians are now using PCbased ignition scopes capable of a wide range of diagnostic displays and modes. For average circumstances, a high-quality digital storage oscilloscope (DSO) will suffice. Whatever the choice, keep in mind that training opens the door and that practice makes perfect when using a scope to analyze ignition system performance.

RAMPING UP CURRENT Because access to secondary waveform testing is nearly impossible on modern COP ignitions, most

advanced diagnostic technicians use a lab scope and a low-amperage inductive current probe to measure and display current flow through the coil’s primary circuit.

See Photo 4.

In review, an oil-filled ignition coil requires about 35 amperes of current at 12 volts to produce 20-30 kV, while a modern e-core or coil-on-plug configuration might require as much as 10 amperes of current at 12 volts to produce 30-60 kV of high-intensity spark.

The ICM or PCM primary circuits can be a non-current-limiting design, which creates a pointed current ramp waveform. The ICM or PCM primary circuits can also be a current-limiting design that creates a “flat-

top” waveform indicating that the primary current is being limited to predetermined values.

See Photo 5.

Access to the primary circuit can most often be obtained through the “ignition” fuse in the vehicle fuse box or directly at the primary ignition wiring harness leading to the ignition coils.

In many cases, all of the system’s ignition coils are powered by a single wire, which simplifies attaching an inductive current probe. In COP ignitions with no other access, a set of jumper wires can be used to attach an inductive current probe.

See Photo 6.

Making the Connection When replacing the coil, the connectors should be cleaned and checked for corrosion or looseness to ensure a good electrical connection. Corrosion can cause resistance, intermittent operation, or loss of continuity, which may contribute to component failure. Applying dielectric grease to coil connectors that fit over the spark plugs is also recommended to minimize the risk of spark flashover caused by moisture. On Ford truck engines with COP ignition coils, moisture contamination that causes corrosion is the number one cause of coil failure.

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If the coil driver in the PCM is ruined or if an ICM fails, it’s always good procedure to check the current ramp on the ignition coil.

Remember that most ignition coils shouldn’t draw more than 8 amperes.

If in doubt, compare amperage draw with a similar known-good system.

If a coil is drawing excessive amperage, the primary circuit might be shorted, which, in turn, might ruin the new PCM or ICM. If you’re in doubt about the integrity of any ignition coil, it’s better to replace with new than to risk a costly comeback. ■

Photo 5: This current ramp represents current flow through a coil-on-plug configuration. Notice that the current is about 4.4 amperes and is non-limited.

Photo 6: Access for an inductive probe can be attained on some COP ignitions by installing jumper wires between the coil connector and coil.

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UnderCover

Solutions to S Brake-Related

N

othing is worse than a customer returning to your shop after a brake job complaining of a noise or performance issue. These comebacks can be frustrating because they negatively impact your shop’s productivity and reputation.

The following are 10 tips that can help you more efficiently and effectively solve a brake comeback due to noise.

1. Interview the Customer: Customer interviews are critical to the noise location process. Keep in mind that the grinding noise you hear might not be the squeaking noise that the customer hears. In

most cases, a test drive with the customer might help to identify the noise with which he or she is most concerned.

If the noise is intermittent, use a checklist to help identify the conditions under which the noise occurs. Is it a cold- or warmweather noise? Does it occur when the wheels hit a tar strip or does it occur more frequently on a gravel or washboard surface?

Is it a squeaking, chirping, rattling, knocking or clunking sound? Or, is it a wheel-speed or an engine-speed noise?

If possible, take a test drive with the customer. Oftentimes, many noise complaints are not related to the brakes.

2. Check TSBs: Brake noise is one of the greatest concerns for automakers. A Technical Service Bulletin (TSB) can tell you if there are updated parts, or even if other items on the vehicle, such as a chattering differential or a sloppy driveshaft, are to blame for the noise.

3. Inspection: If a customer is complaining of brake noise, take some time to inspect the entire vehicle. Brake noise could be increased, mimicked or caused by other components like a worn strut mount, tie-rod end or drivetrain components.

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Stopping d Comebacks Adapted from Andrew Markel’s article in

level. This can be very labor intensive, but required on some vehicles where the slides are on the knuckle. Some brake pad manufacturers have developed special clips that can cover the surface.

And, new caliper brackets for most applications are available through most jobbers.

Heating and cooling cycles can weaken springs and anti-rattle clips, which is why they should not be reused. Some springs and clips can be difficult to install. Some anti-rattle clips may resemble Chinese finger traps when you’re trying to reinstall them back on the car. But leaving them out is not an option.

5. Shims: Never reuse a shim. The caliper fingers and pistons can damage the shims. In an

If the vehicle has accumulated more than 500 miles since the brake job was performed, measure rotor runout and disc thickness variation.

4. Hardware: Brake hardware is necessary to keep the pads moving smoothly in the caliper. But, if the pads are loose or bind in the caliper, it will cause noise. The leading causes are mis-installation of the hardware and corrosion, or the components to which they attach. Not taking the time to clean and remove rust from the bracket and caliper can cause a misalignment of the components. Often, the caliper bracket can be corroded to the point where there are pits and voids on the machined surfaces.

One option is to pool or braze welding material in the voids on the bracket and grind the surfaces TomorrowsTechnician.com 25

average pedal application, the shim can be exposed to more than 2,000 lbs. of force. Over a lifetime, this can distort any shim.

Most shims are made of layers of metal and plastic/rubber materials. The metal can corrode and cause the shim to delaminate. The soft materials can lose their elasticity and ability to dampen vibrations.

Most new pad sets include shims, and the quality of the shim typically reflects the quality of the brake pad.

New OE and aftermarket shims can also be purchased separately from the pad sets. Some automakers even introduce shims to combat noise problems that occur while the vehicle is under warranty.

Another option is an aftermarket shim that attaches to the piston. This shim can act as a noise barrier that prevents noise from being transmitted to the caliper. It can also insulate the piston against heat.

6. Lubricants: Brake lubricant can also be used to isolate vibrations between the disc brake pads and the caliper/bracket. Use it on the back of a bare pad or between the pad shim and caliper — but, use it sparingly. If you’re using a two-piece or clip-on style shim, a light coating can be applied to the shims. Don’t glob it on. Excessive lubricant attracts debris that can cause a caliper to stick.

The primary lubrication points in rear drum brakes include the raised pads on the backing plates that support the shoes, the star adjuster mechanisms, hinge points for self-adjusters or the parking brake linkage, and the parking brake cables.

TECH IN TRAINING: DECIPHERING A CLICKING NOISE DURING BRAKING If a 2009-’10 Honda Pilot owner complains that the vehicle is making one or more clicking noises from the front suspension while accelerating or braking, it could be due to a faulty front suspension rear lower arm bushing bracket. If this is the case, replace both front suspension rear lower arm bushing brackets, and check the wheel alignment.

PARTS & TOOL INFORMATION: Lower Arm Bushing Bracket Set P/N 04513-SZA-000 Ball Joint Castle Nut (2) P/N 90365-STX-A00 Lower Arm Flange Bolt, 14 mm (4) P/N 90118-STX-A00 Lower Arm Flange Bolt, 16 mm (2) P/N 90118-SJC-A00 Ball Joint Remover, 32 mm T/N 07MAC-SLOA102 Ball Joint Thread Protector, 14 mm T/N 071AF-S3VA000 Diagnosis: Listen for one or more clicking noise from the front suspension while accelerating from a moderate stop (between normal and abrupt), or while braking.

– If you hear the noise, go to the Repair Procedure.

– If you don’t hear the noise, continue with normal troubleshooting.

Repair Procedure:

1. Raise the vehicle on a lift.

2. Remove the front wheels.

3. Remove the lock pin from the lower arm ball 26 February 2013 | TomorrowsTechnician.com

Figure 1

7. Rotor Finish: Poor rotor finish can lead to noise. When machining a rotor, you have two primary goals: Provide a smooth surface finish for the pads and provide a true surface finish.

The smoothness of the friction surface of a rotor is described in terms of micro-finish or RA factor. RA stands for “roughness average” and represents a way to measure the smoothness of a rotor. When in good condition and used properly, most lathes available in the market will yield very acceptable RA factors. The finish is essential to transfer material for organic and ceramic friction materials. The correct finish is also essential for semi-metallic pads so they can have the correct coefficient of friction during initial break-in.

Non-directional finishes can help in the “bedding” process and the establishment of a transfer layer. It can also prevent the grooves of the rotor from pulling and pushing on the pad, much like how a record moves a needle. Always clean the rotor’s surface after machining the rotor in order to remove metal fragments that can contaminate the pad.

joint, then remove the castle nut. See Figure 1.

4. Disconnect the lower arm ball joint from the knuckle using the ball joint thread protector and the ball joint remover.

Note: Be careful not to damage the ball joint boot when installing the remover. Do not force or hammer on the lower arm, or pry between the lower arm and the knuckle. You could damage the ball joint.

5. Remove the mounting bolt from the rear side of the stabilizer bar bushing holder.

6. Remove the 14 mm and 16 mm lower arm mounting bolts, then remove the lower arm. See Figure 2.

8. Caliper Issues: A caliper can cause a noiserelated comeback. Every floating caliper has bushings that are designed to isolate vibration in the caliper.

These bushings should last at least two sets of pads.

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Figure 2

They are located on the end or are around the guide pins. Over time, these pins can become compressed and lose their elasticity. This can cause movement in the caliper and possibly even noise. It can also cause uneven application of the pads.

9. Wheel bearings: A worn wheel bearing can cause brake noise and even a low pedal. Too much end play can result in uneven application of the pads. When the pads do not contact the rotor evenly, it can result in a noise complaint.

If the wheel bearing’s flange has too much runout, it can cause disc thickness variation or, in extreme cases, a low pedal. Even if there was no pulsation right after the brake job, a pulsation problem will occur in 2,000-5,000 miles.

Lateral runout can be corrected by replacing the bearing or flange. A less expensive option is to use a plate that can be placed between the rotor and flange.

10. New brake pads: Choosing to install a new set of pads should be 7. Remove the lower arm stops. See Figure 3.

8. Remove the self-locking nut from the rear lower arm bushing, then remove the rear lower arm bushing bracket. See Figure 4.

9. Install a new bushing bracket on the lower arm, and then align the angle of the lower arm center line and the lower edge line of the bushing bracket as shown in Figure 5 on page 33.

10. Install a new self-locking nut, and then tighten it to 162 Nm (119 lb.-ft.).

Figure 3

Figure 4

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the last option when trying to solve a noise complaint. Most of the time, the pad is not to blame if you use a high-quality pad.

Look at the surface of the used pad for any discoloration, cracking or glazing. These are signs of contamination of the friction surface. In order for a pad to operate quietly, it must have a consistent coefficient of friction across the face of the pad that comes in contact with the rotor. If an edge or half of the pad is contaminated by brake lube, metal shavings from the lathe or even friction material from the old set of pads, it will cause a noise comeback.

Most ceramic pads transfer a layer of friction material to the rotor.

This can improve rotor life and braking performance. If the brake pads are changed and the transfer layer of material is left on the rotor, the friction material can become contaminated and the new material might not transfer its material to the rotor. Some friction materials might be compatible but, chances are, the two materials will have problems.

When a rotor is machined or a new rotor is installed, it should be cleaned. The surface should be free of shavings and anti-corrosion coatings. These materials can contaminate the pad and affect the levels of friction across the pad, as just mentioned.

One place you never, ever want to get any grease on is the friction surface of a brake lining — which is another reason for not using lowtemperature or petroleum-based lubricants which can melt, run off and foul the linings. Grease-contaminated shoes or pads will be grabby and usually cause a brake pull to one side.

This is why any brake lubricant should be used sparingly.

In most cases, the contamination can’t be removed from a pad. The pad, therefore, should be replaced and the rotor should be machined.

Returning pads is getting more and more difficult. Some friction suppliers have even eliminated returns for some of their lines. â–

32 February 2013 | TomorrowsTechnician.com

11. Install the lower arm stops. See Figure 3.

Note: Align the slot on the lower arm stop with the lug portion on the front side of the lower arm bushing.

Figure 5

12. Install the lower arm with new bolts: – Lightly tighten the bolts.

– Raise the suspension to load it with the vehicle’s weight before fully tightening the bolts. Do not place the jack against the ball joint on the lower arm.

– Torque the 14 mm bolts to 93 Nm (69 lb.ft.), and torque the 16 mm bolt to 162 Nm (119 lb.-ft.).

– Install the mounting bolt on the rear side of the stabilizer bar bushing holder, and torque it to 39 Nm (29 lb.-ft.)

13. Degrease the threaded section and the tapered portion of the ball joint pin, the ball joint connecting hold, and the threaded section and mating surfaces of the castle nut. Connect the ball joint to the lower arm, being careful not to damage the ball joint boot when connecting the knuckle.

14. Torque the castle nut to the lower torque specification (103-113 Nm [76-83 lb.-ft.]), then tighten it only far enough to align the slot with the ball joint pinhole. Do not align the castle nut by loosening it. Insert the lock pin.

15. Repeat steps 3 through 14 on the other side of the vehicle.

16. Clean the mating surfaces on the brake discs and the inside of the wheels, then install the front wheels.

17. Check the front wheel alignment, and adjust it, if needed.

Courtesy of ALLDATA. TomorrowsTechnician.com 33

Engine Series Adapted from Bob McDonald’s article in

Problems that Plague the Power Stroke

I

f there was one engine that plagues the mid-size diesel world, you would have to say that it is the 6.0L Power Stroke. This engine has the worst repair history that has plagued and continues to plague Ford truck owners today. Even though the engine was only produced from 2003 to 2008, truck buyers often steer away from these engines when purchasing a diesel truck. One comment often heard is, “Why did International stop producing the 7.3L engine?”

Well, there are some areas that need to be covered as to why the 6.0L came into existence and some remedies for the problems that some say ruined the Ford truck reputation for these model years.

6.0L ORIGINS The 6.0L came into existence because the EPA demanded tighter emissions laws for diesel engines. Even though the 7.3L was branded as the reliable workhorse for Ford, it would never be able to pass the tighter emissions laws that were going to come into effect for 2004.

In saying that, I often feel that owners of 7.3L Power Stroke engines don’t realize that their engine was designed to

This is the engine that owners see when looking under the hood of the 2003 Ford Super Duty truck. The 7.3 was replaced by the 6.0 that would make its mark on the mid-size diesel truck market, but not in a good way.

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This is the soot that forms inside the intake when you incorporate an EGR valve.

Simply remove the elbow from the intake manifold of your 6.0 and see for yourself.

meet emissions also.

That was why the HEUI design of the 7.3L was released in 1994.

Tougher emission laws were coming into effect in the mid ’90s, so they were ahead of the game as far as meeting emission standards and having a very dependable engine with the 7.3L. This was one of the reasons that these engines were fitted with a catalytic converter.

To meet the emission standards of 2004, the EPA would require diesel engines to be cleaner. These standards meant that fewer nitrogen-oxide levels of diesel exhaust could be released into the air. For International, this was the start of the snowball that would slowly start its descent down the long hill. The only way to cut down on emissions was to utilize an EGR (Exhaust Gas Recirculation) valve and come up with a more efficient engine. In saying that, you have to realize that the 7.3L was a good engine, but it was not very efficient. As soon as you install an EGR valve on a diesel engine, power drops pretty quickly. If you are wondering why, let me explain.

EGR ISSUES When incorporating an EGR valve on a diesel engine, the object is to bring exhaust gas back into the intake manifold to be re-burned. When the exhaust gas enters the intake manifold, you have displaced the oxygen that was being brought in from the outside air for combustion.

TomorrowsTechnician.com 35

for several hours. Sometimes they would ignore the EGR cooler leak and continue to drive the vehicle until one day the engine wouldn’t turn over. What would happen was the cooler would leak into the exhaust system overnight. The leak would be so bad that the exhaust manifolds would fill up with coolant, which would run into a cylinder with an exhaust valve open.

This would cause the engine to hydro-lock, which could bend a connecting rod when trying to start the engine.

POWERING UP THE POWER STROKE

The EGR valve is placed in the 6.0 manifold to the lower left of the oil filter near the intake “mouth.”

There was a lot at stake for International. Not only did they build a smaller engine that is more efficient and able to carry an EGR valve, but it also had to make power.

Customers wouldn’t want an engine with less power.

So, the 6.0L was a great accomplishment versus the 7.3L. It is still an HEUI design, but now has four valves per cylinder. The combustion chambers in the pistons have been redesigned along with the addition of a VGT (Variable Geometric Turbo).

When making a smaller package, you tend to lose room for fasteners. By redesigning the HEUI engine, the cylinder heads went from six head bolts per cylinder to four. Which should not be a problem, but the engine was faced with a lot of boost, especially if you install a programmer. The VGT was designed to utilize boost throughout the rpm range.

If you remember, the 7.3L made great torque down low and wouldn’t make boost until the engine was up in the rpm range. With the small 6.0L, in order to make

So then, combustion temperature drops because there was not a complete burn. This in turn makes soot, which starts clogging up everything. But, before you can introduce exhaust gas into the intake manifold on a diesel engine, you have to cool it.

Under a load, diesel exhaust gas temperatures can get as high as 1,000° F or more. So, exhaust gas travels through what is known as an EGR cooler. This is a cooler that is circulated with coolant from the engine, and is mounted under the intake manifold.

Exhaust gas travels out of the manifold through an opening in the pipe, which then enters the cooler before exiting into the intake manifold. One of the problems that the 6.0L had was that the EGR cooler would not “live” too long. Over a period of time, the coolers would bust from the exposure to the extreme heat.

When this happened, antifreeze would seep out into the exhaust system causing steam. A lot of times, owners would often notice this when they pulled up to a stoplight. Clouds of steam would pass by them while they were waiting for the light to change.

The EGR cooler lies in the upper valley of the engine beneath the intake Owners would often notice manifold. Here, the intake has been removed to show its location between a puddle of antifreeze under the oil cooler and cylinder head on the passenger side of the engine. the vehicle after being parked

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may have had them replaced once didn’t mean that you wouldn’t have to replace them again.

TURBO TROUBLE

The Variable Geometric turbo sits sideways on top of the engine. The oil feed line is bolted to the top of the turbo. Directly below the oil feed line is the actuator that controls the “vanes” of the turbo.

Having the turbo as a variable geometric style meant problems as well. The turbo was a great addition by Garrett, but having soot in the exhaust system from the EGR valve meant that the “vanes” would stick. The vanes of the VGT are on the exhaust side of the turbo and are controlled by an actuator that is fed with oil pressure from the engine, which is used to cool the turbo. The actuator is controlled by the PCM and will move the vanes, which are mounted to a rotating plate with oil pressure.

The vanes actually change the way the exhaust gas enters the turbo and spins the exducer wheel. So the turbo speed is controlled by the PCM based on input from the other sensors of the engine.

This is a great way to make power throughout the entire rpm range until the vanes stick due to soot buildup.

power down low, you had to make more boost to propel the engine.

This would prove to be a problem with four head bolts per cylinder. The bolts in question are called torque-to-yield, meaning that when they are torqued down properly, they stretch to the correct limit and clamp the gasket.

But, what happens when you force a high level of boost into the engine, stretching the bolts more? You end up with an over-stretched bolt that unclamps the head gasket and causes a leak. So, one of the many problems was leaking head gaskets. Just because you

This is the top of the engine with the oil filter base removed. Remove the outer bolts of this cover that fasten to the top of the engine to access the oil cooler.

NOT COOL

Here, the exhaust side of the turbo has been removed from the turbo body. Above the exducer wheel is the arm that is controlled by the actuator of the turbo.

38 February 2013 | TomorrowsTechnician.com

With a smaller engine package, you have to start coming up with inventive ways to place things on the engine. A great example would be the oil cooler. Some of your instructors may remember the 7.3L, the oil cooler was mounted externally on the driver’s side of the engine, just below the deck of the cylinder block. If there were any problems, the oil cooler could be accessed fairly easily for repair.

But on the 6.0L, the oil cooler is mounted inside the top of the engine under the oil filter. There aren’t really any issues with leakage as much as the cooler itself becoming clogged. Because of the design of the cool-

In this picture, the vanes of the turbo are connected to a wheel that will rotate a few degrees in either direction to move the vanes. The wheel moves from the arm that is located in the housing above the exducer wheel. Here, the vanes are in a closed position, which is going to cut off incoming exhaust gases from spinning the turbine wheel. er, over a period of time, the passages become clogged, causing a rise in oil temperature. Because oil is used to lubricate the turbo and operate the injectors, along with cooling the pistons, this becomes a major problem.

AFTERMARKET FIXES The following are the most common failures of the 6.0L engine. But, because of updates and the help of the aftermarket, a lot of the 6.0L issues can be solved to make this engine very reliable.

We’ll start with the EGR cooler. There are two ways to approach this.

One would be to delete the cooler and delete the EGR valve. Of course in doing this, the engine would no longer be emissions compliant. This really doesn’t seem to matter too much to a lot of owners unless the state they live in has tough emission laws.

One kit that I have found to have great success with is the EGR delete from Gillett Diesel (www.gillett diesel.com) from Bluffdale, UT. The delete kit comes with all the necessary gaskets and hardware to delete the EGR cooler.

Another solution to the problem is to install a better cooler made to handle the job. This would be from Bullet Proof Diesel (www.bulletproof diesel.com) from Mesa, AZ. Their EGR cooler has a totally redesigned cooler core made entirely from stainless steel, which will not fail from normal stress like the OEM style.

Either choice of repair will take around four to five

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The vanes are in an open position, which will allow more exhaust gas to enter the turbine housing, which in turn will spin the turbine wheel faster. hours of labor. One thing that I will say is, either way you choose, if the vehicle has some miles on it, take the time to replace the oil cooler. While you’re removing the intake to perform this repair, it would be wise to go ahead and replace the oil cooler while you will be looking right at it.

This is where you would have to make another decision. The OEM cooler is going to cost around $350 from the dealer. You can replace the cooler with this part, but remember, you may be faced with this repair again.

My suggestion is to ask the customer if they plan keep the vehicle for many more years. If they do, you

Here is a look at the engine once the EGR kit is installed. Once the EGR cooler is removed, the exhaust pipe that feeds the EGR cooler is now blocked from a plug that is supplied with the kit.

The EGR cooler from Bullet Proof diesel is the one on the left, the factory cooler is on the right. The difference can be seen as to the quality of the aftermarket EGR cooler. may want to recommend to them a better cooler like the one also offered from Bullet Proof Diesel. Their design moves the oil cooler to the front of the vehicle. The oil cooler will no longer be mounted inside the engine.

So, if problems would arise in the future, the repair would be a lot simpler to address. The only drawback is the price. This style of cooler does cost more than OEM, but the design and integrity is way far superior.

Something else that I always encourage is to clean the turbo, especially if you’re going to delete or replace the EGR cooler. The turbo has to come off of the engine in order to remove the intake to access the EGR cooler. So why not take the time to clean the turbo? This isn’t a hard job, but you’ll need to pay attention to how the turbo comes apart.

Loosen the large clamp around the exhaust housing of the turbo. Next, pry the exhaust housing away from the body of the turbo. Lay the turbo on a bench with the intake side facing up.

When prying the exhaust housing away from the turbo, the vanes will remain in place on the exducer side so you can see how they are oriented in the turbo. Take the time to clean the vanes along with the rotating plate. A lot of times you’ll notice that not only does the turbo contain soot, but also rust and scale that will cause the vanes to stick. Once this cleaning is performed doesn’t mean that it won’t happen again. But, it may give you a better understanding of how the turbo functions.

The last thing to talk about would be the head gaskets. This repair is going to come sooner or later. My

TomorrowsTechnician.com 41

suggestion is to fix this the first time. There are two different repairs that I’ve found that will cure the problem.

If you purchase OEM-style gaskets, they will work just fine. The gasket material is MLS (Multi-Layer Steel), which has been used by automakers for several years now.

The only reason I see gaskets fail are due to the bolts that stretch.

So you can use the OEM head gaskets, but I suggest the use of head studs. The choice of head studs would be from ARP (Automotive Racing Products), which has been manufacturing quality fasteners for the racing industry for years. The studs are formed from a material like hardened chrome-moly, which has a tensile strength of 190,000 psi.

Once installed correctly, these studs will never stretch, which should never cause any fatigue on the gasket.

The only problem with running MLS head gaskets is the deck surface and head surface must be absolutely smooth. This is referred to as the RA (Roughness Average).

If there are imperfections in the surface of the block or head, it will need to be machined in order to obtain the proper seal.

When MLS head gaskets are torqued, they often leave imperfections in the deck of the block and head because the steel gasket is embedding itself into the surface. If you are faced with this situation, there is another option for repair.

There is a 6.0L head gasket made by Hypermax for these imperfections. The gasket is made of a graphite material just like the ones used on the 7.3L engines. In addition, the cylinders are insulated with stainless steel “fire” rings, which completely seal the cylinders. These gaskets live under the toughest conditions and will not blow unless you add more than one programmer to your vehicle.

STACKED AGAINST YOU Most head gaskets on the 6.0L engine tend to fail quicker when a programmer is installed. Most aftermarket companies try to keep their programmers at around 65 hp for this engine.

Some companies will offer more, but you play at your own risk.

Adding more power tends to accelerate the stretching of the head bolts.

By installing a head gasket from Hypermax, most programmers can be installed without any detrimental effects. Hypermax even guarantees them to 650 rear wheel horsepower. If your engine makes more than 650 hp at the rear wheel, you’d have to be installing more than one programmer. They tend to call this “stacking” chips.

By understanding the design complications of these engines and communicating these issues to your customer, you should have no problem making money treating the problems that plague Ford’s 6.0L engine. ■

service Advisor

Tips 20 for TpMs success

T

hese days, replacing tires – whether as a maintenance item, repair or due to switching out winter tires – will probably put you in contact with a Tire Pressure Monitoring System (TPMS). That’s because all new light-duty vehicles sold in the U.S. after September 2007 were required to be equipped with TPMS. The following are tips to help you in the success of servicing TPMS units, keep your customers (and employer) happy and reduce the chance of a comeback due to a mistake.

Remember, even if the TPMS light is out when the vehicle leaves the bay, it does not mean the light will not come on later. Usually, this happens

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when the customer is driving home.

According to NHTSA TPMS rules, the TPMS system has 20 minutes to alert the driver there is a problem with the system like a damaged sensor from a mounting error. It may take the vehicle achieving a programmed speed or other event to perform a check of the sensors. This is why looking up the service procedure is required if you are performing any TPMS work and perform a little bit of quality control after the repair.

1. Rim Service. Every time a stem-mounted TPMS sensor is removed from a rim, it must be serviced — no ifs, ands or buts.

This goes for sensors that are six months old to six years old.

Do not reuse seals or stems.

2. Use the Whole Kit and Kaboodle. The typical kit includes a nut, valve core, grommets and valve cap. Each component has a specific function and lifespan that is not only determined by time, but what happens when it is installed.

3. One in the hand is worth two on the shelf. Inform the shop owner or dealership manager to have an assortment of TPMS sensor service kits on hand. If your shop even sells a few tires a week, your shop should stock an assortment of service kits. Most tire product suppliers have assortments or cabinets filled with the kits you will need. Not having the parts to service sensors might result in a car stuck in a bay that could be used for other repairs.

4. Aww Nuts! Never reuse the nut. TPMS nuts are designed in anodized aluminum to eliminate the contact of two dissimilar metals that would create galvanic corrosion and material deterioration. The nut has a bonded lubricant to help provide the proper torque required for seating a new grommet, in addition to the engineered advantages. If a nut is reused, the anodized surface may be scratched away and corrosion may occur between the sensor, wheel and stem. It may even make the nut impossible to torque to the correct specifications or remove due to corrosion on the threads.

5. Replace the Grommets. Never reuse the seals/grommets. On the sensor and nut, two grommets seal the sensor and nut to the wheel.

Grommets conform to the mating surface of the rim. The instant the nut is torqued, it starts to take on the shape of the surfaces it is sealing against. This memory cannot be erased. If the seal is reused, it could cause a slow leak.

6. Wrenching Issue. Always use a torque wrench when servicing sensors. As stated in Tip 4, the nut and grommet seals are one-use items. The torque specifications are measured in inch-pounds and not foot-pounds for a reason. The nuts are made of aluminum and will strip. The hollow stems can take only so much abuse before they break.

7. Tightening Nuts. The leak cannot be eliminated by tightening the nut even more. The sealing grommets are engineered to work at a specific torque. Any torque above the specified value will cause the seal to leak.

Also, extra force may damage the nut, stem or fracture the sensor body.

8. Never Reuse the Valve Stem.

Replacing the valve stem core on TomorrowsTechnician.com 45

TPMS sensors prevents leaks. The elastomeric rubber and plastics degrade over time due to heat. The valve stem is subjected to heat from both the brakes and road. Also, a torque calibrated driver should be used to tighten the valve core.

9. Always use the valve core that is in the kit. A TPMS valve core is nickel-plated and prevents galvanic corrosion and ensures integrity of the primary seal. To prevent galvanic corrosion, never use a brass valve core with an aluminum TPMS sensor. Instead, always use a nickel-plated valve core with an aluminum TPMS sensor. It is usually the correct one in the kit. If the wrong valve core is used, accelerated galvanic corrosion could result in the core becoming “frozen” and seized, stuck in the stem and unable to be removed. Also, TPMS valve cores have special Teflon coatings that help seat and seal the stem.

10. Set the Correct Tire Pressure. Seasonal temperature change can dramatically alter tire pressure, which can cause the tire pressure warning lamp to illuminate.

“Cold” tire pressure, as shown on the tire pressure label on vehicles, is generally considered to be the pressure in a tire that has not been driven in the past 4 hours and has been parked outdoors. Tire pressure

46 February 2013 | TomorrowsTechnician.com

drops about 1 psi for every 10 degrees F drop in ambient temperature. Additionally, tires lose as much as 1.5 psi per month as air escapes the tire and rim naturally.

11. Proper Dismount. Take extra care when mounting and dismounting tires. When you are using a tire changer, always be aware where the TPMS sensor is located and avoid all possible contact with shovels, bead breakers and tire irons. Also, some Ford sensors are mounted on the rim 180º from the valve stem.

12. Check Stem ID. In the past three years, there has been a shift to rubber valve stems by Ford, GM and other manufacturers. At first glance, they look just like the valve stems from a non-TPMS vehicle. But, the cap will be longer and the stem will have more threads when compared to a conventional stem. This can help a tech avoid damaging a sensor by accidentally pulling the stem.

Regardless of the valve stem’s appearance, every 2008 and later vehicle has a TPMS system.

13. No More Soap and Water. Dry air and humid air have different properties. TPMS sensors are calibrated

to deal with normal ranges of humidity found in the real world. But, if water is trapped inside the tire, it can change how the pressure relates to temperature.

Humidity or amount of moisture in the atmosphere changes the density of air. Surprisingly, the more moisture results in lower air density. At high humidity, the air density inside the tire decreases due to the reduced mass in a given volume. This will cause the TPMS light to come on as the tire cools or heats up.

If your shop is using a solution of soap and water to help in the mounting of tires, you could be leaving enough water inside the tire to change how the pressures react under changing temperatures. Use only mounting paste, the price of a tube is less than the cost of a comeback.

14. Waiter Inflation. The pressure on the door jam placard is set for cold tires (setting for at least three hours). If you have a customer brings a vehicle in for an oil change and is waiting, you should add 2-4 psi to the recommended placard inflation because the tires are hot. This can prevent the light from coming on after the tires cool down.

15. Spare A Moment. Before you start a relearn procedure, check to see if the spare tire has a sensor.

Often, the service information will make the relearn procedures generic so it can be used for a variety of models. Often the spare is the last sensor to be tested in a relearn procedure. This can be frustrating because it may seem like the vehicle will not relearn the new positions, when it is actually it is waiting to get information from the spare.

sleep mode. Manufacturers of sensors are putting sensors in this mode to increase the shelf life of sensors by conserving the battery. Waking up a new sensor may require a rapid deflation or driving. Check the service information or the sensor’s manufacturer information.

19. Be Patient. When a relearn process is started, vehicles want only one sensor “talking” at a time.

Sometimes, the sensors are active and sending out signals because the vehicle was repositioned or there is radio interference.

For the sensors to go into a sleep mode, the car has to be “still” for a programmed amount of time.

If you are having a difficult time with a relearn procedure, let the vehicle sit for 20 minutes. This should put the sensors into sleep mode. This allows the sensors to be turned on one at a time so the IDs and positions can read by the TPMS system.

20. Chuck the Chuck. If you only work on light vehicles, the long-style air chuck should not be in your shop. These chucks can damage aluminum valve stems because they can create enough leverage to bend or break the stem. ■

16. Record the IDs. If you are installing new tires, on some vehicles it is a good idea to record the sensor ID numbers and positions before the new tires are mounted. Some vehicles including Nissan, Toyota and Honda vehicles require that the sensor IDs be entered into the TPMS module through the DLC. This can really save time if something goes wrong during the relearn process and a sensor is not showing up in the memory.

17. Take Up Training. Training is one of the most important investments you can make for two reasons.

First, it can prevent damage to sensors and lost productivity trying to diagnosis a relearn problem.

Second, it prevents you from sending a customer to the dealer where they could be lost forever.

TPMS is always changing so constant training is required to keep up with new systems and sensors.

18. Rude Awakening. Technicians may become frustrated by new sensors stuck in storage or “super” TomorrowsTechnician.com 47

Bulletin Board Wisconsin Student to Compete in International WorldSkills Competition Kieron Kohlmann of Racine, WI, who's enrolled at Ferris State University in Big Rapids, MI, will represent the United States in Leipzig, Germany in the Automobile Technology competition during the biennial WorldSkills Competition. Kohlmann will compete as a member of the U. S. “WorldTeam.”

The 42nd international event will be held July 2-7, 2013. Kohlmann was recently awarded the gold medal and received “best in nation” in Auto Service Technology in November 2012 during the WorldSkills America’s competition in Brazil where the United States competed against 23 other countries in preparation for the WorldSkills Competition.

Kohlmann won the right to compete by winning the high school gold medal in the Automotive Service Technology contest during the SkillsUSA Championships in June 2010. He also successfully completed other qualifying prerequisites prior to being chosen for the team. Kohlmann works at Bohl Automotive in Racine and took automotive technology classes at Washington Park High School which has an ASE/NATEF certified program.

For more information about the competition, go to: www.worldskills.org or www.worldskillsleipzig2013.com.

Scholarship Money Available Applications are now accepted online for the 2013 Global Automotive Aftermarket Symposium (GAAS) scholarship awards. The application process is now entirely electronic through the GAAS scholarship website, www.AutomotiveScholarships.com.

The deadline to apply is Sunday, March 31, 2013.

The scholarships are available to students in twoyear technical college programs and vocational schools and four-year college programs. To receive

ACROSS 1. Not firing on all cylinders 5. Common automotive fastener 8. Grease fittings, informally 9. Wheel shafts 10. Bench-mounted tool 11. Simple 4x4-system (4,4) 13. Appraisal criteria, ____ wear and tear 15. Piston type, construction-wise 18. Large, stamped-metal body part 19. Oil-burner exhaust color 22. Adjust toe-in 23. Odometer info 24. Chopper backrest, a.k.a. ____ bar 25. Cylinder-ridge removal tools

a GAAS scholarship, applicants must be enrolled full-time in a college-level program or an ASE / NATEF (National Automotive Technician Education Foundation) certified automotive technical program. Graduate programs and parttime undergraduate programs do not qualify.

By completing a single online application at the GAAS website, students will be considered for GAAS scholarships, plus scholarships from a number of industry partners.

Tomorrow’s Technician February Crossword

DOWN 1. Suburban-family vehicle, often 2. Tire-tread slits 3. No-throttle engine speed 4. Removable item with ratchet sound (3,3) 5. Electronic engine-diagnosis device (4,4) 6. Tire characteristic, ____ resistance 7. Turbo safety valve, ____gate 12. Carmaker's written guarantee 14. Yellow-bumper NASCAR drivers 16. Compression-ignition engines 17. Persuader in tool box 18. Tire troubles 20. Extended car-rental document 21. Restorer's parts source, ____ market

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