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PCM Message Not Received

Monitored & Set Condition

  1. When Monitored: With the ignition in run, and the IOD fuse installed.
  2. Set Condition: The BCM does not receive any messages from the PCM for at least 30 seconds.

Possible Causes:

Testing

  1. Turn the ignition on. With the DRBIII(R), enter Body Computer, system Tests then PCM Monitor. Does the DRBIII(R) display: PCM is active on BUS? If yes, with the DRBIII(R), erase DTC's. Cycle the ignition switch and check for BCM DTC's. If DTC resets, replace the Body Control Module. BODY CONTROL MODULE  . Perform BODY VERIFICATION TEST  . If no, go to next step.
  2. Turn the ignition on. With the DRBIII(R), attempt to communicate with the PCM. Was the DRBIII(R) able to communicate with the PCM? If yes, go to next step. If no, see COMMUNICATIONS in DIAGNOSTIC TROUBLE CODE IDENTIFICATION  table. Perform BODY VERIFICATION TEST  .
  3. NOTE: Do not connect the tester to the DRBIII(R).
  4. Turn the ignition off. Disconnect the PCM C3 harness connector. Connect the diagnostic junction port tester No. 8339 to the diagnostic junction port. Measure the resistance of the PCI Bus circuit between the diagnostic junction port tester and the PCM connector. Is the resistance below 5.0 ohms? If yes, replace the Powertrain Control Module. See POWERTRAIN CONTROL MODULE  . Perform BODY VERIFICATION TEST  . If no, repair the PCI Bus circuit for an open. Perform BODY VERIFICATION TEST  .