Working on 2001 astro van. Had engine running. The front was up in the air. Fuel guage was reading quarter of tank. Engine had eng temp sensor that did not mate with connector. I replaced eng temp sensor then lost fuel pump and fuel guage. Went back the next day under wet conditions and removed cover on fuel pump relay and forced relay to complete circuit. Fuel pump ran but then lost all lights on the cluster except battery indicator. No communication with ecm. Found blown fuse on cig lighter circuit and replaced with good. Still no lights or communication with ecm. Prior to losing everything scan tool would only communicate with ecm when key was in run position prior to engine running.

 

I purchased a matching number ecm for $25.00. I opened the original ecm case and examined the board.
No signs of burns or swelling on anything. I did note a sliver of metal which may or may not have been creating a link between two solder points. I opened the second ecm to verify this was not a connection which had failed. No sliver on second board.

 

Wow, you got more guts than I do fooling around with the ecms aren't they really expensive? I don't know about 2001s but a 1995 has a fuse for each ecm.

 

The ecm is only a computer board in a protective case. The salvage yard I do business with has a set price for these things. $25.00 for an ecm and $32.00 if I want a warranty. The warranty means I can return the ecm if it did not work. I could try another or have a credit at the yard.