Powertrain Diagnostic Procedures: Introduction: Notes

The procedures contained in this article include specifications, instructions, and graphics needed to diagnose the PCM Powertrain System. The diagnostics in this article are based on the failure condition or symptom being present at the time of diagnosis.

Please follow the recommendations below when choosing your diagnostic path.

1. First make sure the DRBIII® is communicating with the appropriate modules; i.e., if the DRBIII® displays a "No Response" condition, you must diagnose this first before proceeding.
2. Read DTCs (diagnostic trouble codes) with the DRBIII®.
3. If no DTCs are present, identify the customer complaint.
4. Once the DTC or customer complaint is identified, locate the matching test and begin to diagnose the symptom.

An * placed before the symptom description indicates a customer complaint.

When repairs are required, refer to the appropriate service procedures for the proper removal and repair procedure.

Diagnostic procedures change every year. New diagnostic systems may be added; current systems may be enhanced. READ THIS ARTICLE BEFORE TRYING TO DIAGNOSE A VEHICLE DTC. It is recommended that you review the entire article to become familiar with all new and enhanced diagnostic procedures.