Powertrain Diagnosis

DTC P0604

DESCRIPTION
This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM). This diagnostic also addresses if the ECM is not programmed. The following DTCs are diagnosed in this DTC table:

IMPORTANT: The DTCs listed below, are not applicable to all vehicles.
- DTC P0601 control module read only memory (ROM)
- DTC P0602 control module not programmed
- DTC P0603 control module long term memory reset
- DTC P0604 control module random access memory (RAM)
- DTC P0606 control module internal performance

TEST DESCRIPTION

Steps 1-7:

The numbers below refer to the step numbers on the diagnostic table.
2. A DTC P0602 indicates the ECM is not programmed.
4. Attempt to program the ECM. If the ECM fails to program a second time, replace the ECM.