P0604-INTERNAL CONTROL MODULE RAM

For a complete wiring diagram Refer to Section 8W.

Theory of Operation


After the controller is reset (ignition turned to the RUN position), the microprocessor checks the integrity of each RAM location by writing to it and reading back from it. The read value should be same as value written.


  • When Monitored:

    One time after the controller is reset (ignition turned to the RUN position).

  • Set Condition:

    Whenever the Powertrain Control Module (PCM) detects an internal controller problem.


Possible Causes
  
POWER OR GROUND CIRCUIT
  
POWERTRAIN CONTROL MODULE
  

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)



Diagnostic Test

1.CHECK WIRING AND CONNECTORS FOR INTERMITTENT OPERATION


NOTE: Due to the integration of the Powertrain and Transmission Control Modules, the transmission part of the PCM has it's own specific power and ground circuits.





Were there any problems found?

Yes


No