Hey folks, I'm getting a trouble code telling me my PCM is not getting a correct checksum? At least I think that's what the guy said. I've done some reading and it apparently means I've got a bad PCM or the input voltage is wrong or I've got grounding issues. I've decided I want to try a PNP refurb PCM but I want to be sure I've got good power and ground before I get one, and so far I can't find any tutorial or specific instructions on how to check those things, or would I be better off hiring this done? Any help would be greatly appreciated.