PO601

[hallz]

Anyone have information as to what causes this and how to resolve it?

Most people just say to replace the PCM, but what causes it?

[GMPX]

PCM has detected a checksum error in the Flash or the ETC system has detected a major fault and the PCM will shut down.

You can only fix it by removing / resetting the Flash chip, or a new PCM, it's not good news when it happens. It's much worse when it happens on a 1998 PCM......don't ask me how I know that :cry:

Now, the question I am not sure I want the answer to, do you have a PCM in that state?.

Cheers,
Ross

[hallz]

Yes I do (not my car thank god) Paul replied on LS1-tech to another one of my threads. Thanks guys!!

There were some issues with the fuel system that are resolved now. But I just wnted to make sure, or try to anyway, that anything that may have caused it was fixed before putting in a new PCM.

Would (could) a electriacl componet such as a over stressed fuel pump cause anything like that?

I know when you start placing a higher load or demand on any circuit it can play hell in everything. This car had to have a fp that was working doubble time since it had no scrader valve in the pump and the regulator was stuck open.