P0604 - Internal Control Module Random Access Memory Error
Possible causes
- Loose or poor battery terminal connection
- Low battery charge
- ECM power supply circuit is open or shorted
- ECM Programming
- Faulty ECM
Tech notes
Check the ECM/PCM fuse, if fuse is OK try erasing the code first and if the code comes back you may have to reprogram or replaced the ECM/PCM.
When is the code detected?
Indicates the ECM has experienced an internal memory fault.
P0604 Description
The ECM continuously monitors its own internal memory status, internal circuits, and output signals transmitted to the throttle actuator. This self-check insures that the ECM is functioning properly. If any malfunction is detected, the ECM will set the code and illuminate the engine light.