40/41TE Automatic Transaxle (GPEC)

P0604-INTERNAL CONTROL MODULE RAM

For a complete wiring diagram Consult Diagrams/Electrical.

Theory of Operation

After the controller is reset (ignition on from an off position), the microprocessor checks the integrity of each memory (RAM) location by writing to it and reading back from it. The read value should be the same as the written value. If the memory integrity check fails the MIL will illuminate after 10 seconds of vehicle operation and transmission will be placed in limp-in.

- When Monitored:
One time after each time the ignition is turned to the run position from an off position.

- Set Condition:
The read value does not match the written value in any memory (RAM) location.





Always perform the 40/41TE Pre-Diagnostic Troubleshooting procedure before proceeding. Testing and Inspection

Diagnostic Test

1. PCM - INTERNAL ERROR
If there are no possible causes remaining, view repair.

Repair

- Using the schematics as a guide, check the Powertrain Control Module (PCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. Check for any Service Bulletins that may apply. If no problems are found, replace and program the PCM. With the scan tool perform the Quick Learn procedure.
- Perform 40/41TE VERIFICATION TEST 40/41TE Transmission Verification Test