For 1990-2009 cars

Important: New service TCMs contain DTC P0602. When the TCM is reprogrammed with the correct software and calibrations, DTC P0602 will no longer be an enabled DTC.

DTC P0601-P0604 are type A DTCs.

DTC | Description | DTC Parameters | Diagnosis
--- | --- | --- | ---
P0601 | TCM Read Only Memory | This DTC will set when the TCM determines that its EEPROM/flash memory has been corrupted or if a wrong software or calibration checksum has occurred. | Record all TCM DTCs and include with the repair information. Replace and reprogram the new TCM.
P0602 | TCM Not Programmed | This DTC will set if the TCM is not programmed correctly. | Record all TCM DTCs and include with the repair information. Reprogram the new TCM. If this fault returns, replace the TCM and reprogram the new one.
P0603 | TCM Long Term Memory Reset | This DTC will set when the TCM determines that a non-volatile memory checksum failure has occurred. | Record all TCM DTCs and include with the repair information. Replace and reprogram the new TCM.
P0604 | TCM Random Access Memory | This DTC will set when the TCM determines that its random access memory has been corrupted. | Record all TCM DTCs and include with the repair information. Replace and reprogram the new TCM.