2002 gmc envoy p0604
- Thread starter mrmhoskins
- Start date
gmac310
Member
- Dec 4, 2011
- 174
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.
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.
Mooseman
Moderator
Welcome to the Nation!
If you could fill in your profile as to model, engine, etc. And in your post, more details such as mileage, symptoms, maintenance history and any work done lately would be helpful.
If you could fill in your profile as to model, engine, etc. And in your post, more details such as mileage, symptoms, maintenance history and any work done lately would be helpful.
When it runs with my a/c on for a period of time it misfire once my reduce speed light came on I changed the throttle body once a while back but it was use do u think that could cause itgmac310 said:
Do u think the throttle body would cause it I had trouble with that a while back I replaced it but it was used
Mooseman
Moderator
For the P0604, check to be sure that the connector at the PCM is properly connected.
While you're there, you should clean the throttle body and disconnect the battery for at least 30 minutes to reset everything. Was the used TB you installed dirty at the time? Your original TB might have still been OK but just dirty. Do a search to find threads on how to clean it.
If after all that you are still getting the P0604, I would suspect that your PCM is faulty. These PCM rarely fail but the few that do seem to have this error. You can pick up a used PCM from any TrailBlazer/Envoy of the same year and engine and install it. Just needs a security relearn which you can do yourself.
While you're there, you should clean the throttle body and disconnect the battery for at least 30 minutes to reset everything. Was the used TB you installed dirty at the time? Your original TB might have still been OK but just dirty. Do a search to find threads on how to clean it.
If after all that you are still getting the P0604, I would suspect that your PCM is faulty. These PCM rarely fail but the few that do seem to have this error. You can pick up a used PCM from any TrailBlazer/Envoy of the same year and engine and install it. Just needs a security relearn which you can do yourself.
Mooseman
Moderator
2002 gmc envoy po604 I changed the throttle body that solved it for me thanks to MooseMan great deal buddy!!!
Mooseman
Moderator