Automatic Transmission Diagnostic Procedures: Introduction: Notes

IMPORTANT: The 2007 RS/RG model year vehicles will use both the standard EATX controlled transmission and the NGC controlled transmission based on the available powertrain combinations. You will need to identify which controller is being used on the vehicle that requires service.

Diesel engines use a Transmission Control module (TCM) with an Engine Control Module (ECM).
Gas engines use the Powertrain Control Module (PCM) NGC controller.

PCM - NGC CONTROLLER

RS/RG vehicles use an integrated Transmission Control Module and Powertrain Control Module into a single control module. This module is the Next Generation Controller (NGC) for Daimler-Chrysler and is referred to as the Powertrain Control Module (PCM). The PCM is located in the left front wheel well.

The PCM has four color coded connectors, C1 through C4, (C1-BLK, C2-GRAY, C3-WHITE, C4-GREEN), each PCM connector will have 38 pins. Miller tool #3638, and Miller tool #8815 are used for probing and repairing the PCM connectors. Miller tool #3638 is designed to release the pins from the PCM harness connectors. You must use the Miller tool #3638 to release the harness connector terminals or harness connector or terminal damage will occur. Miller tool #8815 was designed for probing the PCM harness connectors. You must use Miller tool #8815 for probing the PCM terminals or damage to the terminal will occur resulting in a poor terminal to pin connection.

TCM - EATX CONTROLLER

RS/RG vehicles use a Transmission Control Module (TCM) in Diesel powertrain applications. The TCM can be identified by the presence of a single 60 way harness connector. This stand alone TCM module is the used to control the transmission functions and is located in the left front wheel well. The Engine Control Module (ECM) which controls the engine functions is separate from the Transmission Control module.

The procedures contained in this service information include all of the specifications, instructions, and graphics needed to diagnose:

41TE TCM (EATX) Electronic Automatic Transmission problems
40TE/41TE PCM (NGC) Electronic Automatic Transmission problems

The diagnostics in this service information are based on the failure condition or symptom being present at the time of diagnosis. When repairs are required, refer to the appropriate service information for the proper removal and repair procedure. Diagnostic procedures change every year. New diagnostic systems may be added and/or carry over systems may be enhanced.

READ THIS SERVICE INFORMATION BEFORE TRYING TO DIAGNOSE A VEHICLE TROUBLE CODE. It is recommended that you review the entire service information to become familiar with all new and changed diagnostic procedures. This book reflects many suggested changes from readers of past issues. After using this book, if you have any comments or recommendations, please fill out the form at the back of the book and mail it back to us.