MSM-PCM Messages Not Received

MSM-PCM MESSAGES NOT RECEIVED

For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With the ignition in run.

- Set Condition:
The module does not receive any messages from the PCM. Time to mature for the MHSAPM is 2 seconds. Time to mature for the IPM is 2 seconds.





Diagnostic Test

1. PCM MESSAGE NOT RECEIVED
Turn the ignition on.
With the scan tool Instrument Cluster, System Tests then PCM Monitor.
Does the scan tool display: PCM is active on BUS?

Yes

- Erase the DTC, if DTC resets, replace the Memory/Heated Seat Adjustable Pedal Module.
- PERFORM POWER SEAT SYSTEM VERIFICATION TEST - VER 1. Power Seat System Verification Test

No

- Go To2

2. ATTEMPT TO COMMUNICATE WITH THE PCM
Turn the ignition on.
With the scan tool, attempt to communicate with the PCM.
Was the scan tool able to communicate with the PCM?

Yes

- Go To3

No

- Refer to communication . No Response From PCM (Powertrain Control Module)
- PERFORM POWER SEAT SYSTEM VERIFICATION TEST - VER 1. Power Seat System Verification Test

3. PCI BUS CIRCUIT OPEN
Turn the ignition off.
Disconnect the PCM harness connector.

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

Measure the resistance of the PCI Bus circuit between the DLC and the PCM connector.
Is the resistance below 5.0 ohms?

Yes

- Replace and program the Powertrain Control Module.
- PERFORM POWER SEAT SYSTEM VERIFICATION TEST - VER 1. Power Seat System Verification Test

No

- Repair the PCI Bus circuit for an open.
- PERFORM POWER SEAT SYSTEM VERIFICATION TEST - VER 1. Power Seat System Verification Test