Diagnostic Aids
WARNING: This page is about a different car, the 2004 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
Missing data from a module may assist in diagnosing this malfunction. Determine the module that is not communicating by observing the following:
- Transmission Data (TCM)
- Engine Speed (RPM) - This comes from the ECM.
- MIL Request - This goes to the ECM.
- Engine Data (ECM)
- Transmission Speed- This comes from the TCM.
- MIL Request - This comes from the TCM.