Hi

133K miles.

Been reading up on P0601 Checksum error for PCM. Here's where I am at. Replaced PCM with Cardone PN 79-7401V. Live in Cal, but bought van in Denver when we lived there. New PCM throws P0403. Not use what that is, but I didn;t get a P0601 on the new PCM.

Put the old PCM back and got P0601 again. I'm not really good beyond bolting on parts.

I'm stuck. Dealer want $190 to tell me what's wrong. I'm sure they are going to hit me up for a PCM replacement, probably close to $1000.

I'm all ears. Thanks

 

You know the new PCM fixed the 601 and the original PCM did not give you a 403 (EGR failure). Leave the old PCM in the van and send the new PCM back for a replacement. I'm betting you aren't seeing any symptoms besides the check engine light.

Even if the dealer said it was a bad PCM and they wanted $1000 you are in no way obligated to say ok get me a new PCM. You would pay them the $190 and say thank you for troubleshooting it and drive away. That said, save your $190 and do this yourself. You really already have.