P0605

P0605 - Internal Control Module ROM

For a complete wiring diagram, refer to.

Theory of Operation

After the controller is reset, the microprocessor checks the integrity of the 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. The MIL will illuminate and the transmission will be placed into limp-in after 10 seconds of problem identification.

• When Monitored: One time after the ignition switch 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. Refer to => Non-DTC Based Diagnostics. Pre-Diagnostic Troubleshooting Procedure

Test Step 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 PCM terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. Check for 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 the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test