Suburban TSBs

Where can I read more about technical service bulletins?

Specifically:

99-07-30-016B OCT 02 A/T - Intermittent Downshift/Slip/Cycling Diagnosis

02-06-03-009A OCT 02 Battery - Charging/Information Tips

02-06-03-010 OCT 02 Battery - Parasitic Drain Information

02-03-07-002 OCT 02 Steering/Suspension - Revised Camber/Caster Adjustment

02-06-01-028 AUG 02 Engine - Crankcase Flushing Recommendations

02-06-03-006 JUL 02 Battery/Charging System - Diagnosis/Testing

02-08-47-001 JUL 02 Body Control - Update of Some Control Module DTC's

02-05-25-002 JUN 02 ABS - Wheel Speed Sensor Replacement Revision

02-06-04-023A JUN 02 Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set

99-08-51-007A MAR 02 Aluminum Wheels - Refinishing

02-06-04-015 MAR 02 Engine - Intermittent No Crank/No Start

02-06-04-005 FEB 02 Engine Controls - Revised DTC P1221

01-07-30-036A JAN 02 A/T - 4L60E/4L65E DTC P0756 Diagnostic Tips

02-07-30-001 JAN 02 A/T - 4L60E/4L65E DTC P1870 Diagnostics

02-07-30-003 JAN 02 A/T - New Design Reaction Shell Thrust Washer

02-02-35-001 JAN 02 Ignition Lock Cylinder - Revised Replacement Procedure

01-07-30-042 DEC 01 A/T - 4L60E/4L65E 2nd to 3rd Gear Upshift Clunk

01-07-30-043 DEC 01 A/T - Slipping/Missed Shifts Diagnostic Tips

01-06-01-028 DEC 01 Engine - Knocking Sound On Cold Start

00-02-35-003A DEC 01 Steering - Underhood Clunk Noise

01-03-10-011 DEC 01 Tires - Sidewall Damage

01-06-04-044 NOV 01 EVAP System - Special Tool Usage

01-08-56-004A SEP 01 Antitheft System - Lamp ON/Stall/No Start/DTC B2960 Set

01-08-56-005 AUG 01 Theft Deterrent - Revised Diagnostic Information

01-08-56-002A JUN 01 Security System - Lamp ON/DTC B2960 Set

99-01-39-004A MAY 01 A/C - Odor Emission in Hot Weather

Diagnostic Information for Intermittent Transmission Downshift, Slip, Busy/Cycling TCC or Noisy Cooling Fan #99-07-30-016B - (10/14/2002)
Diagnostic Information For Intermittent Transmission Downshift, Slip, Busy/Cycling TCC or Noisy Cooling Fan
1999-2000 Cadillac Escalade

2002-2003 Cadillac Escalade, Escalade EXT

1988-2003 Chevrolet Astro, Blazer, S-10, Silverado, Suburban

1989-2003 Chevrolet/Geo Tracker

1995-2003 Chevrolet Tahoe

1996-2003 Chevrolet Express

1988-1994 GMC S-15

1988-1999 GMC Suburban

1988-2003 GMC Safari, Sierra

1995-2003 GMC Sonoma, Yukon, Yukon XL

1996-2003 GMC Savana

1999-2001 GMC Envoy

1991-2001 Oldsmobile Bravada

2003 HUMMER H2

with Air Conditioning

This bulletin is being revised to change the Model information and text. Please discard Corporate Bulletin Number 99-07-30-016A (Section 07 -- Transmission/Transaxle).

Some customers may comment that at times the transmission seems to slip, or that there is a loud roar from the engine with slow acceleration. This condition is most noticeable after the vehicle has sat idle for 12 or more hours, or on hot days when the A/C is on and the vehicle moves slowly with traffic. Typical comments from customers may include the following conditions:

Intermittent slipping
Intermittent downshift followed by an upshift, both with no apparent reason
Busyness or cycling of the TCC (torque converter clutch) at steady throttle conditions and on a level roadway
Noisy cooling fan
The type of concern described above requires further definition. The customer should be asked the following questions:

Is the situation more pronounced with higher vehicle loads such as when pulling a trailer?
Do warmer ambient temperatures make the situation more pronounced ?
When the condition occurred, did you have the A/C on, and were you driving in stop and go city traffic?
Does the condition exhibit itself on the first startup after sitting more than eight hours?
If the customer indicates that these conditions apply, and your observation confirms that the vehicle is operating properly, provide the customer with the vehicle operating description included at the end of this bulletin. Further action may not be necessary. A service procedure follows if further definition is required.

Diagnostic Aids
Cooling fan operation or the resulting sound varies. The cooling fan clutch may be described as a continuously variable clutch. If the vehicle engine is running, the fan blade is always turning unless the fan clutch is non-functional. The speed of the fan in relation to engine speed is temperature dependent. Maximum fan speed (air flow and related fan noise) through the engine compartment is experienced under two conditions.

When the vehicle sits in an unused condition for several hours, the viscous fluid within the thermostatic fan clutch assembly migrates and fully engages the clutch of the fan. After a short drive, the viscous fluid will migrate to the storage area in the fan clutch and the fan clutch will slip, reducing the noise (roar of the fan). This is normal thermostatic fan clutch operation.
When the engine is running, and the air being drawn by the fan or pushed through the radiator from the vehicle movement reaches a high enough temperature, the fan clutch will fully engage the fan clutch, drawing additional air through the radiator to lower the engine coolant temperature and A/C refrigerant temperature. When the cooling fan clutch fully engages, fan noise increases (for example; this is the same as switching an electric household fan from low to high speed). Some customers have interpreted this sound increase to be an increase in the engine RPM due to transmission downshift, transmission slipping, or TCC cycling. As the engine coolant temperature decreases, the fan clutch will begin to slip, lowering the actual speed of the fan blade and the resultant sound.
Service Procedure
When diagnosing an intermittent transmission downshift, slip, or busy/cycling TCC, follow these steps:

Verify the transmission fluid level and the fluid condition. Refer to the Automatic Transmission sub-section of the appropriate Service Manual.
Test drive the vehicle under the conditions described by the customer (ambient temperature, engine coolant temperature, trailering, etc.). It may be necessary to partially restrict airflow to the radiator in order to raise the engine coolant temperature to match the customer's conditions.
Monitor the engine RPM and the engine coolant temperature using a scan tool.
Listen for an actual increase in the engine RPM. Use either the vehicle tachometer (if equipped), the Tech 2 RPM or transmission slip speed as an indicator, rather than just the sound.
If the engine RPM display on the tachometer or the Tech 2 increases, verify the scan tool RPM and coolant temperature readings. If the noise increase is due to the engagement of the fan, the engine RPM will not increase and the engine coolant temperature will begin to decrease after the fan engages. As the fan runs, the engine coolant temperature will drop and the fan will disengage, reducing noise levels. The engine RPM will not decrease. This cycle will repeat as the engine coolant temperature rises again.

If the above procedure shows the condition to be cooling fan-related, no further action is necessary. The vehicle should be returned to the customer and the condition explained.

If the above procedure shows the condition to be other than cooling fan-related, refer to the Automatic Transmission sub-section of the appropriate Service Manual for transmission diagnosis information.

The following information regarding the operation of the engine cooling fan should be photocopied and given to the customer.

Intermittent Transmission Downshift
All light duty trucks are equipped with a thermostatic engine cooling fan. This fan is designed to provide greater fuel efficiency and quieter operation than a standard fan. These benefits are possible through the addition of a thermostatic clutch to the fan drive.

When the engine is cool (if the engine has been run in the last few hours), the clutch allows the fan to "slip" or turn at a speed slower than the engine. By turning at a slower speed, the fan uses less horsepower, which saves fuel, and is quieter. When the engine temperature reaches a preset temperature or if the engine has not been run for several hours, the fan "engages" and turns at the same speed as the engine.

"Engagement" of the fan provides increased airflow through the radiator to cool the engine. As the airflow increases, fan operation becomes clearly audible. This increase in noise can easily be mistaken for an increase in engine RPM and may be incorrectly blamed on the automatic transmission. When operating an unloaded vehicle in cooler ambient temperatures, the thermostatic clutch usually won't fully engage. However, if the vehicle is pulling a trailer, is heavily loaded or is operated at high ambient temperatures, the thermostatic fan clutch may cycle on and off as the engine coolant temperature rises and falls.

The sound of fan operation under the conditions described above is a sign that the cooling system on your vehicle is working correctly. Replacement or modification of the cooling system or the transmission parts will not change or reduce the noise level. Attempts to reduce this noise may cause you, the customer, to believe that your vehicle is not reliable and will inconvenience you by causing your vehicle to be out of service.

Info - Battery Charging Tips #02-06-03-009A - (10/14/2002)
Battery Charging Tips
1990- 2003 Passenger Cars and Light Duty Trucks

1990-2003 Isuzu Light Duty Trucks

2003 HUMMER H2

This bulletin is being revised to correct the information in the State of Charge table and add additional information about AGM batteries. Please discard Corporate Bulletin Number 02-06-03-009 (Section 06 - Engine/Propulsion System).

When you test a battery with a Midtronics Conductance Tester, J 42000 or J 42000-EU, there are five typical outcomes:

Good battery
Good - recharge
Charge & retest
Replace battery
Bad cell - replace
You'll notice that battery charging is called for in two of these outcomes. This bulletin will address charging and chargers in more detail.

What's Involved in Charging
Briefly, charging involves applying sufficient voltage to the battery to cause current to flow through the battery. Charging causes a chemical change in both the battery's plates and the electrolyte. If the battery is simply discharged, but otherwise good, and you apply a suitable current for enough time, the battery will eventually become as fully charged as is chemically possible. However, continued application of current can lead to overheating, loss of electrolyte and shortened battery life.

The charging process requires two things: time and current. If you multiply the charging rate in amperes by the number of hours, the result will be the ampere-hours of charge you've applied to the battery. To bring a battery to full charge will require roughly the same number of ampere-hours at a low charge rate as it does at a high rate. Put another way, a higher rate will take less time.

Because customers desire to have their vehicles returned quickly, it's often desirable to get the charging job done quickly by using a high charge rate. Before doing this, though, you need to know a little more about the process.

State of Charge
OCV (conventional flooded-cell battery)
OCV (AGM battery)
% charge at 0°C (32°F)
% charge at 25°C (75°F)

12.75
12.8
100%
100%

12.70
--
100%
90%

12.60
--
90%
75%

--
12.6
100%
75%

12.45
12.4
75%
65%

12.20
12.3
65%
45%

12.00
12.1
40%
20%


It is not possible to measure a battery's state of charge in ampere-hours, so another method must be used. Open circuit voltage (OCV), measured across the battery's terminals, relates to the battery's state of charge. The voltmeter must be capable of reading to the nearest 0.01 volt.

If the battery has NOT been charged or used (the engine started or the vehicle driven) in the last 12 hours, a reading may be taken.

If the battery has been discharged and recharged or used within the last 12 hours, connect a carbon pile and load the battery at 300 amperes for 15 seconds. Remove the load. Wait 15 seconds and then take the reading.


Important
The OCV reading is accurate +/- 10%.


A battery with a state of charge of 65% or greater ("green eye" showing) is marginally charged enough to be returned to service. However, if the vehicle is or will be used in slow traffic or short drive times, or in very cold or very hot conditions, the battery should be at least 90% of full charge before returning to service (the customer).

Battery Charging and the Reality of the Service Lane
A customer with a "bad" / "discharged" battery typically expects something to be done about it immediately. The customer may not understand that the battery may be "good" but simply discharged. Customers may want to get back on the road quickly and demand a new battery under warranty.

There are two things wrong with this approach. One, if the battery is otherwise serviceable, it may only need a recharge to return it to health. Second, unless the cause of the battery becoming discharged is resolved, neither a new battery nor recharging the original will permanently solve the problem.

Your job, then, is to recharge the battery quickly and safely determine and repair, if necessary, the cause of the battery becoming discharged.

Automatic Battery Chargers
Recent advancements in battery charging technology now combine diagnostics and charging control systems that monitor and automatically regulate the charging process.

These controls maximize the charger's output based on the battery status, while protecting the battery from overcharge. This shortens the overall time by making the most effective use of the charger's output capability. This means you can confidently use chargers with the highest output ratings, so long as the charger makes the necessary adjustments as the battery approaches full charge.

Automatic battery chargers such as the Midtronics GR1, Associated Intell/Matic Pro or the Cristie PDQ can return a good, but discharged, battery (as indicated by your J 42000 tester) to at least 85% state of charge in 20 to 40 minutes. For more information on these chargers, call GM Dealer Equipment at 1-800-GM TOOLS.

Manual Battery Chargers
Non-automatic battery chargers do not offer the self-limiting features of the latest equipment. It is the operator's responsibility to control the charging process. With careful monitoring, you can use a manual charger to successfully charge maintenance-free batteries.

Monitor both charging current and voltage every 30 minutes. Because voltage is not held constant, it will rise as the battery becomes charged.

When voltage reaches 16 volts, you must reduce the charging current to 5 amperes. When the voltage reaches 16 volts again, at the 5 amp current, the battery is fully charged.

Conditions That Affect Charging
A completely discharged battery will take more than twice as long as a half-charged battery to bring the battery to a usable state of charge. The electrolyte in a discharged battery is largely water, which is a poor conductor. The battery may accept such a small amount of current at first that it appears not to take charge.

Chemical reactions in a battery are slower at low temperatures. This means a very cold battery will take longer to charge than one at room temperature.

And, of course, a larger battery will take longer to charge than a small one.

Special Conditions for AGM Batteries
The Absorbent Glass Mat (AGM) battery uses absorbent glass mats to hold a small amount of electrolyte in contact with the plates. The battery uses a gas recombinant technology, which means the gases produced at the plates are recombined to form water before they escape. This battery design offers high power for lower weight and is more resistant to high temperatures, vibration and cycling, which makes it ideal for the Chevrolet Corvette.

The AGM battery may be charged using the automatic battery charger. Laboratory tests have shown that AGM batteries respond very well to such chargers. In fact, even the chargers with the highest output ratings may be confidently used, as long as the charger automatically adjusts the charging current as the battery nears full charge. When the charger operation indicates that the battery is fully charged (refer to the charger manufacturer's instructions), remove the battery from charge.

However, when using a conventional charger, limit the rate to 10 amperes or less. Do not allow the battery to charge at 3 amperes or more for longer than 10 hours, or 10 amperes for longer than 5 hours. When these limits are reached, allow the battery to stand overnight, then resume charging, if further charging is required.

Check the voltage every 30 minutes and remove the battery from charge when the voltage reaches 15 volts at 3-10 amperes. The state of charge is now at 90 to 95%

Info - Battery Parasitic Drain #02-06-03-010 - (10/14/2002)
Battery Parasitic Drain
2003 and Prior Passenger Cars and Trucks

2003 HUMMER H2

2003 Isuzu Light Duty Trucks

In automotive terms, a parasitic drain is an electrical load that draws current from the battery when the ignition is turned off. Some devices, such as the PCM and the radio memory are intended to draw a very small amount continuously. These draws are measured in milliamps (mA).

In normal use, parasitic drains aren't usually cause for concern, because the battery is replenished each time the vehicle is driven. But, in long-term parking situations, parasitic drains may discharge the battery enough to cause a no-start condition. New vehicles in dealer stock and airport long-term parking are two such situations.

An abnormal parasitic drain could be a glovebox or luggage compartment light that remains on but undetected. Or an electronic component may malfunction and cause a parasitic drain that is larger than normal specification.

Parasitic Drains and On-the-Lot Battery Discharge



Important
In most cases of discharged batteries in low-age, low-mileage vehicles, proper charging procedures with approved charging equipment is the only repair necessary.


Here are some rules of thumb that might help relate parasitic drains to how long a battery would last on a parked vehicle.

The Reserve Capacity (RC) rating multiplied by 0.6 gives the approximate available ampere-hours (AH) from full charge to complete rundown. Somewhere between full charge and complete rundown, the battery will reach a point at which it can no longer start the engine, although it may still operate some of the electrical accessories.

Using up about 40% of the total available AH will usually take a fully-charged battery to a no-start condition at moderate temperatures of 25°C (77°F). Put another way, for a typical battery in a storage situation, depleting the available AH by 20 to 30 AH will result in a no-start condition.


Important
If the battery begins storage at 90% of full charge, reduce the available AH accordingly.


The recommendation for maximum parasitic drain is around 30 mA (0.030 amp). A typical drain today actually falls into the 7-12 mA range, even though some vehicles do approach the maximum. Multiply the drain (in amps) by the time (in hours) the battery sits without being recharged. The result is the amount of AH consumed by the parasitic drain. The actual drain may be small, but over time the battery grows steadily weaker.

Here's an example: a vehicle with a 30 mA drain and a fully-charged 70 RC battery will last 23 days. But if that battery is at only 65% of full charge (green dot barely visible), it is going to last only 15 days before causing a no-start.

Effects of Temperature on a Standing Battery
The parasitic drain will be fairly constant over a range of temperatures. The important temperature is that of the vehicle at the time a start is attempted. Colder temperature raises the threshold of a no-start by increasing the residual power needed. When the temperature falls to 0°C (32°F), the battery will be able to put out only about 85% of its normally available starting power, and the engine may need as much as 165% of the usual power to start.

The combined effect of these two factors is to reduce the number of days the battery can stand with a parasitic drain. At 0°C (32°F), the battery can stand only half as long as it could at 25°C (77°F). And at -19°C (0°F), the standing days are reduced to one-fourth.

Temperatures above the moderate climate of 25°C (77°F) increase the battery's internal self discharge. If the battery is in a locale where the temperature is averaging 32°C (90°F), an additional 5% to 10% of the available ampere-hours will be lost in a month due to self-discharge within the battery. At temperatures below the moderate range, self-discharge will be low enough to be negligible compared to the parasitic loss.

What the Policies and Procedures Manual Says About Parasitic Drains
Because determining how long a battery may last in a storage situation is not precise, the P manual provides a clear-cut policy, excerpted here.

"Discharged batteries can freeze at temperatures as high as 0°C (32°F), causing permanent damage. Other permanent damage may result from allowing batteries to stand discharged for extended periods."

"To alleviate this condition, the negative battery cable should be disconnected on vehicles which are not going to be in service within a 20 day period, beginning from the time the vehicle is shipped. If this is not possible, batteries should be recharged periodically, every 20-45 days, until the green eye is visible."

"Disconnected batteries will slowly discharge, especially with higher temperatures; therefore, even disconnected batteries should be checked every four months and recharged if necessary."

"Vehicles on display are subject to battery discharge due to drains from courtesy lights and other accessories. Provision to maintain battery state of charge for these vehicles will be necessary."

Consult your P manual for full details.

Tracking Down the Source of a Parasitic Load
If the battery in a vehicle becomes discharged in a shorter time than described earlier, the vehicle may have an out-of-specification parasitic load. Refer to Service Information (SI) for procedures for locating parasitic drains. Follow these steps:

Build the vehicle.
Select the Engine section.
Select the Engine Electrical sub-section.
Select Diagnostic Information and Procedures.
Select Battery Electrical Drain/Parasitic Load Test.
You will need the J 38758 Parasitic Draw Test Switch and a digital multimeter set to the 10A scale.


Important
Read the procedure and follow the steps exactly as described in SI. The following is a summary, not the complete procedure.


The test switch permits you to place an ammeter in series with the battery negative cable. Before performing the test, the engine must be run and all accessories must be operated as instructed. After shutting the ignition off, turn the test switch off. Now, all the current being used by the vehicle is shunted through the ammeter where it is measured. If the reading is out of specification, the procedure explains how to pinpoint the cause.

A Final Word About Battery Testing
Your dealership has an essential tool, the Midtronics Micro 410 Battery Tester, J 42000. Use it to quickly identify batteries that are serviceable and can be charged. Refer to Corporate Bulletin Number 99-06-03-012 for more information about this tool.

SMU - Revised Front Caster and Camber Adjustment Procedure #02-03-07-002 - (10/04/2002)
Revised Front Caster and Camber Adjustment Procedure
1999-2000 Cadillac Escalade

2002-2003 Cadillac Escalade, Escalade EXT

1999-2003 Chevrolet Express, Silverado, Tahoe, Suburban

2002-2003 Chevrolet Avalanche

1999 GMC Suburban

1999-2003 GMC Savana, Sierra, Yukon, Yukon XL, Yukon XL Denali

2003 HUMMER H2

This bulletin is being issued to revise the Front Caster and Camber Adjustment procedure in the Wheel Alignment sub-section of the Service Manual. Please replace the current information in the Service Manual with the following information.

The following information has been updated within SI. If you are using a paper version of this Service Manual, please make a reference to this bulletin on the affected page.

Front Caster and Camber Adjustment (Cadillac Escalade; Chevrolet Avalanche, Silverado, Tahoe, Suburban; GMC Sierra, Suburban, Yukon; HUMMER H2)

Important
Caster measurements or values must be compensated for the measured frame angle.


Caster is relative to frame. The caster values must be compensated for the measured frame angle by using a digital protractor or equivalent on a flat portion of the frame in front of the rear tire.

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Frame angle is positive when higher in the rear. Measure both sides of the frame and take an average from those measurements. Then add the average frame angle to the caster reading when making adjustments.

http://files.automotiveforums.com/uploads/981539BULLETIN002.jpg

Frame angle is negative when lower in the rear. Measure both sides of the frame and take an average from the measurements. Then subtract the average frame angle from the caster reading when making adjustments.
The caster and camber adjustments are made by rotating the offset cam bolt and the cam in the slotted frame bracket in order to reposition the control arm.

Important
Before adjusting the caster and camber angles, jounce the front bumper three times to allow the vehicle to return to normal height.

Measure and adjust the caster and the camber with the vehicle at curb height. The front suspension Z dimension is indicated in Trim Heights. Refer to Trim Height Inspection Procedure in Suspension General Diagnosis.


For an accurate reading, do not push or pull on the tires during the alignment process.

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Determine the caster angle (2). Be sure to compensate for frame angle where required.

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Determine the positive camber (2) or negative camber (3) angle.
Remove the pinned adjusting cam insert. Do not reinstall the cam insert.
Loosen the upper control arm cam adjustment bolts.

Notice
Refer to Fastener Notice in Cautions and Notices.






Adjust the caster and the camber angle by turning the cam bolts until the specifications have been met. When the adjustments are complete, hold the cam bolt head in order to ensure the cam bolt position does not change while tightening the nut. Tighten
Tighten the cam nuts to 190 N·m (140 lb ft).

Verify that the caster and the camber are still within specifications. Refer to Wheel Alignment Specifications. When the caster and camber are within specifications, adjust the toe. Refer to Front Toe Adjustment.
Front Caster and Camber Adjustment (Chevrolet Express; GMC Savana)





Important
Caster measurements or values must be compensated for the measured frame angle.


Caster is relative to frame. The caster values must be compensated for the measured frame angle. Determine the frame angle by positioning a digital protractor or equivalent between the transmission support (2) and the #3 body mount (3) and obtaining a frame angle measurement.



Frame angle is positive when higher in the rear. Measure both sides of the frame and take an average from those measurements. Then add the average frame angle to the caster reading when making adjustments.



Frame angle is negative when lower in the rear. Measure both sides of the frame and take an average from the measurements. Then subtract the average frame angle from the caster reading when making adjustments.



The caster and camber adjustments are made by rotating the offset cam bolt and the cam in the slotted frame bracket in order to reposition the control arm.

Important
Before adjusting the caster and camber angles, jounce the front bumper three times to allow the vehicle to return to normal height.

Measure and adjust the caster and the camber with the vehicle at curb height. The front suspension Z dimension is indicated in Trim Heights. Refer to Trim Height Inspection Procedure in Suspension General Diagnosis.


For an accurate reading, do not push or pull on the tires during the alignment process.
Determine the caster angle (2) .



Determine the positive camber (2) or negative camber (3) angle.



Remove the pinned adjusting cam insert. Do not reinstall the cam insert.
Loosen the upper control arm cam adjustment bolts.

Notice
Refer to Fastener Notice in Cautions and Notices.


Adjust the caster and the camber angle by turning the cam bolts until the specifications have been met. When the adjustments are complete, hold the cam bolt head in order to ensure the cam bolt position does not change while tightening the nut. Tighten
Tighten the upper control arm nuts to 175 N·m (129 lb ft).

Verify that the caster and the camber are still within specifications. Refer to Wheel Alignment Specifications. When the caster and camber are within specifications, adjust the toe. Refer to Front Toe Adjustment.

Info - Engine Crankcase Flush #02-06-01-028 - (08/09/2002)
Engine Crankcase Flush
2003 and Prior GM Cars and Trucks

2003 HUMMER H2

2003 and Prior Isuzu Light and Medium Duty Trucks

with Gasoline Engines

General Motors is aware that some companies are marketing tools and equipment to support engine crankcase flush procedures. GM does NOT endorse or recommend crankcase flushing for any of its gasoline engines. Analysis of some of the materials used for crankcase flushing procedures indicate incompatibility with GM engine components and the potential for damage to some engine seals and bearings. Damage to engine components resulting from crankcase flushing procedures is not covered under the terms of the New Vehicle Warranty.

No Start, No Crank, Battery, Batteries, Generator, Gages, SES, SIR, Brake, Security, Theft, ABS, Hot, DIC Messages, Lamp, Light, Battery and Generator Diagnostic Testing, and Cadillac Roadside Service #02-06-03-006A - (11/26/2002)
No Start, No Crank, Battery, Batteries, Generator, Gages, SES, SIR, Brake, Security, Theft, ABS, Hot, DIC Messages, Lamp, Light, Battery and Generator Diagnostic Testing, and Cadillac Roadside Service, Warranty Claims Procedure (Proper Diagnostic Procedures)
1997-2003 Passenger Cars and Trucks (Except Electric Vehicles)

2003 HUMMER H2

This bulletin is being revised to clarify the Service Procedures and update the Warranty Section. Please discard Corporate Bulletin Number 02-06-03-006 (Section 06 -- Engine).

IF YOU WISH TO PRINT THE ELECTRICAL SYSTEM DIAGNOSTIC WORK SHEET ONLY, YOU MAY REFER TO CORPORATE BULLETIN NUMBER 02-06-03-011.

Condition
Some customers may have comments regarding any one or more of the following conditions:

Intermittent illumination of one or more of the following instrument panel warning lamps:
SES light
Generator light
SIR light
Brake light
Security, theft light
ABS light
Hot light
Gage readings which seem to be incorrect.
Erratic RPM display on the Tachometer.
Engine is difficult /hard to start.
Engine will not crank.
Check Generator displayed on the Driver Information Center.
The transmission shifts hard.
Noise underhood: growl, rattle, hiss/tapping, grinding.
Quality improvement is a goal of General Motors. As part of the ongoing quality improvement assessment efforts for generators and batteries, General Motors is implementing a new product feedback process.

Generator/Battery Service /Feedback Process
Accurate feedback from technicians will allow General Motors to accurately inspect and diagnose batteries and/or generators replaced in the field.

Why? Testing of the batteries and the generators replaced and returned to General Motors have shown that an extremely high percentage of them are operating within design specifications, also known as Trouble Not Found (TNF).

Therefore, General Motors is modifying the battery and generator testing procedure and supporting documents required when a battery or generator is replaced under warranty.

Testing Procedures

Caution
Batteries produce explosive gases, contain corrosive acid and supply levels of electrical current high enough to cause burns. Therefore, to reduce the risk of personal injury when working near a battery, always shield your eyes and avoid leaning over the battery whenever possible. Do not expose the battery to open flames or sparks. Do not allow the battery electrolyte to contact the eyes or the skin. Flush immediately and thoroughly, any contacted areas with water and get medical help.


Proper Testing requires that the following test procedures be followed;


Important
Complete the "Electrical System Diagnostic Work Sheet" as you perform the test steps outlined below. IF YOU WISH TO PRINT THE ELECTRICAL SYSTEM DIAGNOSTIC WORK SHEET ONLY, YOU MAY REFER TO CORPORATE BULLETIN NUMBER 02-06-03-011.


Battery Inspection and Test Portion


Inspect the battery for evidence of physical damage or leakage. If damage or leakage is found, replace the battery. If no damage or leakage is found, proceed to Step 2. Leaking batteries are to be claimed using failure code "6J" and do not require a Midtronics test code.
If the battery has leaked, the battery tray and surrounding area should be neutralized with a baking soda and water solution. (This is a Straight time: Add operation requiring Service Management authorization).
If the battery has leaked and soaked the battery insulator blanket, a new battery insulator blanket must be installed on the new battery.
Is the hydrometer eye clear (low electrolyte level)? If clear, tap the hydrometer lightly with the handle of a small screwdriver. Did the color change? If no, replace the battery. If yes, continue with Step 3.

Important
The pad/post of the battery must make solid and complete contact with the terminal/connector pad of the battery cable. This interface must be clean and corrosion free. The positive terminal is always sealed to the case by the vinyl covering on the battery cable end. On many vehicles, the negative terminal is also sealed. The attachment bolt is to hold the battery cable end terminal firmly on the battery. It is not designed as the carrier of the current.


Attempt to rotate both battery cables. Properly torqued battery cables will have a break-away torque requirement of 15 N·m (10 lb ft). If the bolt is tight and the battery cable end does not rotate, continue with the next step. If the bolt is tight and the battery cable end rotates, it may be due to one of the following conditions:
The battery cable end may be damaged. Inspect and replace the damaged component as required.
The attaching bolt is cross threaded. Refer to Corporate Bulletin 02-06-04-015 for the proper repair procedure.
The attaching bolt may be too long. Replace the battery cable bolt, if necessary.
Inspect for the presence of foreign material lodged in the battery bolt hole. Repair as necessary.
Connect the Midtronics Digital Battery Analyzer, (tester), J 42000 to the battery terminals. Rock the J 42000 Battery Tester clips back and forth on the cable attaching bolts to cut through any coating or oxidation that may be present. For further information regarding the tester refer to: Testing the Battery with the Midtronics Micro 410 Tester, J 42000, found later in this bulletin.

Important
For AGM batteries, you must enter 100 CCA more than the CCA value displayed on the battery label, when using the Midtronics Digital Battery Analyzer, J 42000.
THE "CCA" READING DISPLAYED ON THE J 42000 SHOULD "NOT" BE COMPARED WITH THE BATTERY'S LABORATORY CCA RATING SHOWN ON THE BATTERY LABEL. THESE NUMBERS ARE NOT RELATED AND ARE ARRIVED AT IN COMPLETELY DIFFERENT WAYS. THE "CCA" NUMBER SHOWN ON THE TESTER WILL JUST ABOUT ALWAYS BE LOWER THAN THE OFFICIAL CCA RATING OF THE BATTERY AND SHOULD NOT BE A CONCERN.

Enter the correct CCA of the battery in the vehicle into the Midtronics Tester, J 42000.
Test the battery with the Midtronics Digital Battery Analyzer, J 42000. The tester will display one of five messages. Refer to the appropriate message below for the next step.
Good battery. (Proceed to the Generator Testing portion of the work sheet).
Good-Recharge. (Recharge the battery. Refer to Corporate Bulletin Number 02-06-03-009. Return to Step 4).
Charge & retest. In this case, the tester has determined the battery state of charge is too low to perform an adequate test. (Recharge the battery. Refer to Corporate Bulletin Number 02-06-03-009. Return to Step 4).
Replace battery. Return to Step 4.
Bad cell - Replace. Go to Step 7.
THE "CCA" READING DISPLAYED ON THE J 42000 SHOULD "NOT" BE COMPARED WITH THE BATTERY'S LABORATORY CCA RATING SHOWN ON THE BATTERY LABEL. THESE NUMBERS ARE NOT RELATED AND ARE ARRIVED AT IN COMPLETELY DIFFERENT WAYS. THE "CCA" NUMBER SHOWN ON THE TESTER WILL JUST ABOUT ALWAYS BE LOWER THAN THE OFFICIAL CCA RATING OF THE BATTERY AND SHOULD NOT BE A CONCERN. If a "Replace Battery" or "Bad cell - Replace" message is displayed on the J 42000, the following steps must be performed before replacing the battery.
Disconnect both battery cables.
Clean the battery terminal pads.
Install test adapters.

Important
Failure to provide the Midtronics "Out of Vehicle" seven digit test code on the warranty claim may subject the claim to rejection.


Perform the Midtronics out of vehicle test.
Record the 7 digit code on the repair order and the work sheet.
Replace the battery. Return to Step 4 and test the replacement battery.

Important
THE "CCA" READING DISPLAYED ON THE J 42000 SHOULD "NOT" BE COMPARED WITH THE BATTERY'S LABORATORY CCA RATING SHOWN ON THE BATTERY LABEL. THESE NUMBERS ARE NOT RELATED AND ARE ARRIVED AT IN COMPLETELY DIFFERENT WAYS. THE "CCA" NUMBER SHOWN ON THE TESTER WILL JUST ABOUT ALWAYS BE LOWER THAN THE OFFICIAL CCA RATING OF THE BATTERY AND SHOULD NOT BE A CONCERN.


Test the replacement battery with the Midtronics tester J 42000, start with Step 4.
Charging System Test



Important
Battery voltage must be higher than 12.4 volts for proper electrical system testing. Without an adequately charged battery, testing of a vehicle generator will result in the replacement of good generators. Therefore, the following test procedures should be followed:


Key in the "OFF/LOCK" position, with a digital multimeter, measure and record the battery voltage at the battery terminals,______Volts. This is known as battery voltage.
Turn "OFF" all accessories.
With the engine running, with a digital multimeter, measure and record the battery voltage at the battery terminals,______Volts. This is known as system voltage.
Is the system voltage reading greater than the battery voltage, but less than 16 volts? Is it? If yes, go to Step 7. If no, go to Step 5.
If no, with the engine running, measure the voltage output of the generator at the generator.___volts.
Was Step #5 voltage greater than the voltage obtained at the battery, Step #3. If yes, a wiring related condition exists with the vehicle. The generator output is not reaching the battery. Diagnose and repair.
With the key "ON", engine "OFF", what is the ignition 1 voltage displayed on the Tech 2®?____volts
Start the engine. What is the ignition 1 voltage displayed on the Tech 2®?_____volts
Engine running voltage should be greater than engine "off" voltage, but less than 16 volts. Is it?
What is displayed on the Tech 2® for Terminal "L" ? (If available).________________
What is displayed on the Tech 2® for Terminal "F" ? (If available).________________
Refer to Service Information (SI), Generator Usage Table, for the vehicle being tested and determine the Load Test and Rated Output values of the generator for the vehicle being tested.
Connect the Sun Vat 40 Tester, or equivalent, to the vehicle. Remember the aqua/blue clamp needs to be placed on the generator output cable(s) as close to the generator as possible. Connect the red clamp to a positive terminal and the black clamp to the engine or a vehicle ground connection. All connections should be made as close to the generator as possible.
With the engine idling, what is the idle RPM _________and the generator ampere output?________amps
Increase the engine speed to 2000 RPM (cars) 2500 (trucks), (highway speed). Use the Sun Vat 40 to place a load on the generator. Adjust the load to the Load Test output value given in the Service Information (SI) for the vehicle (or use 70% of the rated output). Record the generator output__________amps and the ignition 1 or system voltage________ volts.
Is the ignition 1 or system voltage 13-16 volts? (circle one) yes no If not, (or if the Load Test output value could not be reached), replace the generator.
Shipping Preparation
Please wire tie the following documents to the battery or generator being returned so that they do not become separated in handling.

A copy of the Diagnostic Work Sheet.
A copy of the repair order.
Warranty Information
For vehicles repaired under warranty, use:

Labor Operation
Description
Labor Time

N0110
Battery, Remove and Replace (R)
Use published time

J4100
Generator, Remove & Replace (R)
Use published time

N9995
Customer Concern not Duplicated
See Below.

ADD
To complete Electrical System Diagnostic Worksheet
0.7 hr


N0110 or J4100 labor operation may have the following additional time allowance added to the labor operation time for the component replaced. Use this additional time when the Diagnostic Work Sheet must be completed in order to determine which component needed replacement. ADD: To complete electrical system Diagnostic Worksheet, 0.0 - 0.7hr.

N9995, Customer Concern, not Duplicated is a Straight Time Labor Operation code, and should be used when the Electrical System Diagnostic Work Sheet test is performed and no trouble is found with the electrical system of the vehicle. This Labor code has the following note: "Actual time from 0.1 to 0.3 hours spent to perform the diagnosis is to be entered as "Labor Hours" for this operation. Any additional diagnosis time greater than 0.3 hours must be submitted as "Other Labor Hours", and have appropriate Service Management Approval and Authorization.

Leaking batteries are to be claimed using failure code "6J" and do not require a Midtronics test code. The work sheet is not required and the add should not be applied for.

Battery claims, other than leakage, will require the use of the tester and reporting of the tester 7-digit code on the warranty claim.

Cadillac Roadside Service
Cadillac Roadside technicians (during a roadside repair) cannot test and recharge batteries. Use the following procedure when replacing a battery on a roadside visit.


Important
Battery testing procedures should be followed after returning to the dealership.


The technician should take the battery back to the dealership and perform a Midtronics test, J 42000.
The code should be included in the comment section of the warranty claim when the claim is submitted.
If the battery is found to test good, note the code in the comment section of the claim followed by the verbiage BATTERY GOOD - - ROADSIDE REPAIR.
Background Information
Batteries
What is a battery? The battery is a reservoir. Think of a battery as a water tower (reservoir) for your city's water system.

The water tower stands some 60 feet in the air. The forces of gravity on the volume of water in the tower determines the pressure within the system.

Opening a valve in the water system allows water to flow through the pipes to the consumer. Water flowing from the tower lowers the force of gravity (pressure) on the volume of water standing in the tower. If the water is not replaced, pumped into the water tower (recharged), the water system pressure would drop. The volume of the water being released from the system determines the discharge rate.

When defining pressure in an electrical circuit, the term volts is used as compared to pounds per square inch in other systems.

A battery is made up of 6 individual cells. Each individual cell is able to store a small amount of pressure (voltage). Each individual cell has the capacity of approximately 2.1 volts (pressure). When the 6 individual cells are connected in series, you have a 12.6 volt battery. The pressure (voltage) of the battery may be measured and displayed on a digital multimeter.

A piece of stranded wire, with only one strand (which could be as small as the hair on your head) making contact with the battery source, will show either battery voltage with the engine off, or system voltage when the engine is running.

Voltage readings do not indicate the volume of (current/amperage) electrical energy available. Your diagnostic routine must determine the amount of electrical energy (amperage) available.

For example, a new AAA battery, as used in a flash light, has a voltage level of approximately 1.6 volts. If you place 8 AAA flash light batteries in series and measure them with a multimeter, the result will be a reading on the multimeter exceeding 12 volts. The question: will this 12 volts start a vehicle engine? The answer is No. Why not? The volume (amps) is not sufficient to energize the cranking motor.

Amperage/current are terms used to define the volume of electrical energy within an electrical circuit. Batteries store amperage under pressure (voltage).

Turning on a switch within an automotive electrical system allows current (amperage) to flow through the connecting wires to the consumer (the consumer in an electrical system is any motor, bulb, actuator or other device). The current (amperage) flowing from the battery reduces the voltage (pressure). If the current/amperage is not replaced by charging, battery voltage will drop.

Think of it this way. Amperage does the work; voltage is the pressure. When you touch a 110 volt AC current source at home, you get quite a shock because of the amperage available. How many of you have seen another technician or yourself feel the wallop of the ignition systems 40,000 + volts. There is very little current here, however, if the amperage were higher, the technician would suffer extreme consequences.

What does a battery green eye really mean? A green eye means the cell in which the eye is placed is more than 65% charged, however, other cells in the battery may be low on electrolyte, or a cell may be internally shorted and the battery may not perform properly. The green eye is an indicator of the state of charge of that particular cell. The green eye is an attempt, when all things in all cells are equal, to give a hydrometer indication of the one cell and apply that to the entire battery. To properly test a suspect battery, you must use the Midtronics Battery tester.

Testing the Battery with the Midtronics Micro 410 Tester, J 42000



Important
The Midtronics Micro 410, J 42000, (tester) helps identify battery problems. However, it is NOT CAPABLE OF TESTING THE CHARGING SYSTEM (GENERATOR) OR PERFORMING PARASITIC LOAD TESTS.


The Midtronics Digital Battery Analyzer, (tester), J 42000, should be used to determine the state of health and charge level of the battery prior to any battery or generator replacement (unless physical damage is found to either the battery or the generator). The tester, J 42000, uses conductance technology instead of traditional load testing. The tester allows you to test most batteries that are partially discharged without first performing the time consuming charging and load testing procedure. The tester helps quickly identify batteries that are serviceable and just need to be re-charged. Battery testing is best performed in the vehicle at the battery terminals. If you cannot access the battery terminals, remove the battery and test the battery out of the vehicle. As with any electrical test, a good connection is very important to battery testing.

Generators
The automotive generator is a highly complex electromechanical device. Generators apply the principles of magnetic induction to automotive electrical systems to supply proper current (amperage) and voltage (pressure) regulation during all driving conditions.

Proper testing of the generator requires that the battery be at a full state of charge. The generator's voltage and ampere outputs will be controlled/regulated based on the battery's state of charge. The generator's internal voltage regulator monitors the vehicle system voltage and will control the charging system voltage output. Controlling the charging system in the range of 13.5 to 16.0 volts prevents over/under charging of the battery, depending on the generator used in the vehicle.

Generators internally produce alternating (AC) current. Before it reaches the generator's output terminal, conversion to direct (DC) current is required for automotive use.

All generators use a voltage regulator to regulate the amount of voltage (pressure) the generator maintains on the system.

All generators have a specified or designed maximum amperage (volume) rated output capacity.

A series of 6 diodes, in a rectifier system, (rectifier bridge), converts AC to DC voltage and current.

The faster a generator's rotor spins, the higher the available output of current (amperes). Generator output is directly related to engine speed (high engine speed = high available current output; low engine speed (idle) = low available current output).

Ampere output of the generator must be larger than the vehicle usage requirements or a battery discharge condition will occur.

A generator operating at engine base idle may not charge a battery unless all consumers of energy, i.e., A/C, heated seats, rear window defogger, headlights, etc. are off, and then only a small current (ampere) level may be charging the battery.

For example, a generator with a rated output of 100 amps, at 1500 engine RPM, will show the following characteristics when a diode within the rectifier bridge has a problem:

The generator with one failed positive diode will produce the proper regulated voltage however, only about 66 amps output.
If two positive diodes are defective, the generator will still produce the proper regulated voltage. However, only about 1/3 (33 amps) of rated output will be available.
Failed negative diodes have an effect, too, but this is generally related to shortened generator life and not to reduced output.
Consider a hypothetical example. If a vehicle requires 65 amps of current to maintain vehicle operation (i.e. radio, heater, heated seats, air conditioning, clock, memory modules, and the list goes on), at idle (650 RPM), the generator produces, say 50 amps. The balance is made up by the battery. If the generator produces 100 amps at 2000 RPM, 65 amps are used by the vehicle and the excess (35 amps), is available for recharging the battery. Over time, the generator replenishes the battery and keeps it in a fully charged state.

A customer who only drives the city streets at low speeds, especially in the winter with the headlights, heated seats, wipers, rear window defroster, and heater blower on, is discharging the battery. For a generator to produce maximum output, the engine speed must be in the 2000 RPM range or higher.

Batteries are like people in some ways. They work best when the ambient temperature is around 22°C (72°F). At a temperature of -17°C (0°F), the battery is only 60 % efficient. At high ambient temperatures above 27°C (80°F), the battery wears out quicker due to the catalyst effect of temperature on the chemicals within the battery.

Battery Charging
Before charging a battery, inspect the battery for the following:



Inspect the battery for evidence of physical damage. If damage is found, replace the battery. If no damage is found, proceed to the next step.
Is the hydrometer eye clear (low electrolyte level)? If clear, tap the hydrometer lightly with the handle of a small screwdriver. Did the color change? If no, replace the battery. If yes, continue with the procedure.

Important
If an attaching bolt is stripped, it is usually possible to clean the battery terminal threads with a thread chaser and avoid replacing the battery. The threads in the battery terminal are harder than the bolt threads, so only the attaching bolt usually needs to be replaced.


Inspect for loose, stripped battery cables. Attempt to rotate the battery cable end. Properly torqued battery cables will have a break-away torque requirement of 15 Nm (10 lb ft). If the bolt is tight and the end rotates, it may be due to the following conditions:
The attaching bolt is cross threaded.
The attaching bolt may be too long.
There may be foreign material lodged in the battery bolt hole.
The battery cable end may be damaged.
Battery cable to battery interface corrosion.
A clear eye (low electrolyte level rather than a green or a black eye.
Test the battery with the Midtronics tester, J 42000. The tester may detect an internal problem with the battery before time is spent charging the battery. The test procedure is listed below under testing procedures. The test will advise the technician to charge and retest the battery when appropriate.

Electrical System Diagnostic Work Sheet

ALL REQUESTED INFORMATION MUST BE PROVIDED

To Complete this work sheet, you will need the following tools: A Fluke digital multimeter J 39200, J 39688 or J 39978.

The Midtronics Battery Tester J 42000. A Sun VAT 40 Tester or equivalent. The Tech 2® Scan Tool

Today's Date:__________

Repair Order Number__________

Vehicle Delivery Date:______________
Mileage: __________miles _________km

VIN: _______________________

Dealer Code _______ Dealership Phone Number ____ ____ ______ Technician Number/Name ___________

Customer concern (as written on the repair order):



Was the vehicle towed to the service center? (Circle one) Yes No

What is the voltage displayed on the DIC (if equipped) key "ON" engine "OFF"? ______volts.

Start the engine. What is the voltage displayed on the DIC (if equipped) with the engine running? ______ volts.

Is the service engine or service vehicle soon lamp illuminated? (Circle one) Yes No

Which lamp(s)? __________________________________________________

List all diagnostic trouble codes as displayed by the scan tool (Include all P, T and U DTCs) Current/Active and History:

Record the freeze frame or failure records for those codes present (use additional sheet if necessary).





Battery Inspection and Test Portion:
Refer to Corporate Bulletin # 02-06-03-006 for additional information.

Is the hydrometer eye (if equipped) clear (low electrolyte level)? (Circle one) Yes No. If clear, tap the hydrometer lightly with the handle of a small screwdriver. Did the color change? (Circle one) Yes No. If no, replace the battery. If yes, continue
Does the battery show evidence of leaking or physical damage. (Circle one) Yes No If "NO", go to Step 4.
If "YES" replace the battery. Then continue with the next step.
Are both battery cable to battery connections clean and tight. If not, repair connections.

Important
When using the Midtronics 410, J 42000 tester on Corvette AGM batteries, you must enter 100 CCA more than the CCA value displayed on the battery label. When using the Midtronics 411A, J 42000 EU, enter the batteries rated CCA..


Test the battery with the Midtronics Digital Battery Analyzer, J 42000. What message is displayed on the tester (Circle one) good battery, good-recharge, charge & retest, replace battery, bad cell - replace.
Were you instructed to charge the battery? (Circle one) Yes No
Have you completed the recharge? (Circle one) Yes No. Refer to Corporate Bulletin # 02-06-03-009 for battery charging info.

Important
The "CCA" reading displayed on the J 42000 is NOT intended to be compared with the batteries laboratory CCA rating shown on the battery label. These numbers are not related and are arrived at in completely different ways. The "CCA" number shown on the tester will just about always be lower than the official CCA rating of the battery and should not be a concern.


Were you instructed to replace the battery? (Circle one) Yes No. What was the eight digit message displayed on the tester after the "Out of Vehicle" test. __________. For information on the out of vehicle test procedure, refer to Corporate Bulletin # 02-06-03-006.
Test the REPLACEMENT BATTERY with the J 42000 tester? What is the displayed message? (Circle one) good battery, good-recharge, charge & retest, replace battery, bad cell - replace.
Was the message: good recharge, or charge & retest. Have you charged the battery? (Circle one) Yes No.

Charging System Test:



Important
Battery voltage must be higher than 12.4 volts for proper electrical system testing.


Key in the "OFF/LOCK" position with a digital volt meter, measure and record the battery voltage at the battery terminals. ____ Volts.
Turn "OFF" all accessories
With the engine running, with a digital volt meter, measure and record the battery voltage at the battery terminals. ____ Volts.
Voltage measured in step #3 should be greater than step #1, but less than 16 volts. Was it? (Circle one) Yes No
If no, engine running, measure the voltage output of the generator at the generator. _____Volts.
Was Step #5 voltage greater than the voltage obtained at the battery, Step #3? (Circle one) Yes No. If yes, a wiring related condition exists with the vehicle. The generator output is not reaching the battery. Diagnose and repair. If no, continue with the next test procedure.
Key "ON", engine "OFF", what is the Ignition 1 voltage displayed on the Tech 2®. ______Volts.
Start the engine. What is the ignition 1 voltage displayed on the Tech 2®. _________Volts.
Voltage from step #8 should be greater than step #7 but less than 16 volts. Was it? (Circle one) Yes No
What is displayed on the Tech 2® for Terminal L? (if available)________
What is displayed on the Tech 2® for Terminal F? (if available)________
Refer to Service Information (SI), Generator Usage Table, for the vehicle being tested. Determine the load test and rated output value of the generator for the vehicle being serviced. The generator has a load test value of__________Amps and a rated output value of____ Amps. Note: the rated output is the maximum amperage the generator will produce under ideal conditions at approximately 2000 engine RPM. The load test value is the output value used to test the generator.
Using the SUN VAT 40 Tester, test and record the amperage output of the generator under the following conditions. Use the Tech 2® to determine the engine speed.
Turn OFF all accessories. Increase the engine speed to (2000 RPM cars, 2500 RPM trucks) and adjust the carbon pile (VAT 40) to obtain the maximum amperage output. Record the maximum generator output obtained. ________ amps
Is the ignition 1 voltage displayed on the Tech2® between 13 and 16 volts? (Circle one) Yes No.
Is the maximum amperage output of Step# 14 equal to or greater than the load test value for this vehicle's generator? (Circle one) Yes No.

Technician's Diagnosis: Does the generator/ battery need replacement? Please explain why.______________________________________________ ________________________________________________

__________________________________________________ ________________________________________________

__________________________________________________ ________________________________________________

If a customer concern condition is found with the vehicle, and the suspected cause of the customer concern is suspected to be due to lack of vehicle activity, i.e. storage or driving habits, dealership management should discuss the Parasitic Drain Bulletin # 02-06-03-010 with the customer. Was Corporate Bulletin # 02-06-03-010 discussed with the customer by a member of the dealerships service management team so further customer concerns may be alleviated? (Circle one) Yes No

ATTACH THIS FORM TO THE REPAIR ORDER AND A DUPLICATE COPY TO THE GENERATOR/BATTERY

That should keep you busy for awhile, maybe bowtiebandit will jump in here and post some more for you. As for me it is time to go home.

Originally posted by John
That should keep you busy for awhile, maybe bowtiebandit will jump in here and post some more for you. As for me it is time to go home.
Thank you!!!!!!!!!!!!!!!!!!!!!!! :D

I'll be trying to fix all these problems with my Sub :(

No problem, I will work on it tomarrow again, the official gm site that bowtiebandit and I use is painfully slow so it takes awhile to do.

Also I have notice that Igor has turned the HTML off so it makes it even more difficult to copy and paste the jpg's that are in the bulletins. I started to save and upload them but that took so long I quit.

If you need the illustrations for anything in perticular let me know and I will upload them.

BTW where the heck did you get all of those bulletin numbers from?

:confused:

Originally posted by John
BTW where the heck did you get all of those bulletin numbers from?
Bowtie might be e-mailing me some of those files.

I don't remember the exact site because I've been doing so much research on my vehicle... trying to honestly fix all the "bugs". I came across a list of "known issue" with the 5.3/2001, which included the above TSBs. There were more, but I went through & weeded out the ones that didn't apply to my "bugs".

The easiest solution to all my problems would be to sell the vehicle to some poor sucker... but I really do like the sports-car handling & speed.

Originally posted by DMC12

but I really do like the sports-car handling & speed.


Hahaha... so thats why you got it?

Originally posted by RedNeck383
Hahaha... so thats why you got it?
Yes, not only is it a compact RV (minus restroom) but it can waste stock imports (and one Ford we know of) no prob:devil:

Also, the combination of mass HP and standard diff make for some massive burn-outs (handy when anti-American protesters be frontin').

http://alldata.com/recalls/index.html

All kinds of TSBs ...

- Stu:ylsuper:

Is there a procedure for replacing the window motors in a 2000 Suburban?

Does someone have access to these TSBs for a 93 Suburban?
99-01-39-004A MAY 01 A/C - Odor Emission in Hot Weather
531212A DEC 96 A/C - Odor at Start up in Humid Climates
05-06-02-001 FEB 05 Cooling System - Aluminum Radiator/Heater Core Info.

Thanks.