P0604

P0604-INTERNAL CONTROL MODULE RAM

For a complete wiring diagram, refer to: Electrical Diagrams

When Monitored
One time after the ignition key is turned to the run position.

Set Condition
The read value does not match the written value in any RAM location.

Possible Causes
- PCM - INTERNAL ERROR

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Theory of Operation
After the controller is reset, the microprocessor checks the integrity of each RAM location by writing to it and reading back from it. The read value should be the same as the written value. MIL on after 10 seconds of vehicle operation and transmission will be placed in limp-in.

Diagnostic Test
1. PCM - INTERNAL ERROR
Using the schematics as a guide, inspect the wiring and connectors. Repair as necessary Pay particular attention to all power and ground circuits.
If there are no possible causes remaining, view repair.

Repair
Replace the Powertrain Control Module. With the scan tool perform QUICK LEARN, then program Pinion Factor in the Front Control Module.
Perform 42RLE TRANSMISSION VERIFICATION TEST - Ver 1. Verification Tests.