42RLE Automatic Transmission

P0605-INTERNAL CONTROL MODULE ROM

For a complete wiring diagram refer to Diagrams/Electrical. Electrical Diagrams


Theory of Operation


After the controller is reset, the microprocessor checks the integrity of the program memory (ROM). A checksum is calculated by adding all used bytes in the program memory. The sum should be the same as a known constant stored in memory. MIL on after 10 seconds of vehicle operation and transmission will be placed in limp-in.


- When Monitored:

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

- Set Condition:

If the ROM checksum does not match a known constant.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. 42RLE - Pre-Diagnostic Troubleshooting Procedure



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

- 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 Service Information Tune-ups or Service Bulletins for any possible causes that may apply. If no problems are found, replace and program the PCM. With the scan tool, perform QUICK LEARN.
- Perform 42RLE TRANSMISSION VERIFICATION TEST. 42RLE Transmission Verification Test