Engine Control Module: Technical Service Bulletins
Engine/Transmission - Aftermarket Calibrations
Bulletin No.: 09-06-04-026C
Date: August 13, 2010
Subject: Identifying Non-GM (Aftermarket) Engine and Transmission Calibrations for V8 Gas Engines Using Tech 2(R) or Global Diagnostic System
2006-2011 GM Passenger Cars and Light Duty Trucks (Excluding Saab 9-7X)
2006-2009 HUMMER H2
2006-2010 HUMMER H3
Equipped with V8 Gas Powered Engines Only
This bulletin applies to V8 gas powered engines ONLY. For Duramax(TM) diesel powered engines, refer to the latest version of Corporate Bulletin
This bulletin is being revised to add the 2011 model year. Please discard Corporate Bulletin Number 09-06-04-026A (Section 06 - Engine/Propulsion
General Motors is identifying an increasing number of engine, transmission and catalytic converter part failures that are the result of non-GM
(aftermarket) engine and transmission control calibrations being used.
When alteration to the GM-released engine or transmission control calibrations occurs, it subjects powertrain and driveline components (engine ,
transmission, transfer case, driveshaft and rear axle) to stresses that were not tested by General Motors. It is because of these unknown stresses, and the
potential to alter reliability, durability and emissions performance, that GM has adopted a policy that prevents any UNAUTHORIZED dealer warranty
claim submissions to any remaining warranty coverage, to the powertrain and driveline components whenever the presence of a non-GM (aftermarket)
calibration is confirmed - even if the non-GM control module calibration is subsequently removed.
Warranty coverage is based on the equipment and calibrations that were released on the vehicle at time of sale, or subsequently updated by GM. That's
because GM testing and validation matches the calibration to a host of criteria that is essential to assure reliability, durability and emissions performance
over the life of the warranty coverage and beyond. Stresses resulting from calibrations different from those tested and released by GM can damage or
weaken components, leading to poor performance and or shortened life.
Additionally, non-GM (aftermarket) issued engine control modifications often do not meet the same emissions performance standards as GM issued
calibrations. Depending on state statutes, individuals who install engine control module calibrations that put the vehicle outside the parameters of
emissions certification standards may be subject to fines and/or penalties.
This bulletin outlines a procedure to identify the presence of non-GM (aftermarket) calibrations. GM recommends performing this check whenever a
hard part failure is seen on internal engine or transmission components, or before an engine assembly or transmission assembly is being replaced under
warranty. It is also recommended that the engine calibration verification procedure be performed whenever diagnostics indicate that catalytic converter
replacement is indicated.
The PQC has a process to confirm the ECM/PCM calibration is GM issued. The PQC will require a picture of the engine calibration verification screen,
as outlined in this bulletin, before authorizing any V8 gas powered engine replacement.
If a non-GM calibration is found and verification has taken place through GM, the remaining powertrain and driveline warranty will be blocked and
notated in GMVIS and the dealership will be notified. This block prevents any UNAUTHORIZED warranty claim submission.
1. Connect the Tech 2(R) to the vehicle.
2. Go to: Diagnostics and build the vehicle.
3. Select: Powertrain.
4. Select: Engine.
5. *Select: Engine Control Module or PCM.
6. *Select: Module ID Information or I/M Information System if the Module ID Information selection is not available.
7. *If "I/M information System" was selected, it may be necessary to select "Vehicle Information" in order to display the calibration information.
‹› If the CVN information is displayed as "N/A", it will be necessary to contact the TCSC to obtain the CVN information.