recently tried to troubleshoot with no success my wind./washer pump and caused a dead short with inline switch . discovered the alternator was either on its way out or it took a hit . replaced alt. van ran real rough , just about stall etc. , just as though the computer was trying to correct itself. it still had the Alt. gauge flashing and showing 10V or less . hmm ! checked for battery chargeing and it dropped only when started . turned van off and checked all fuses in and out of box . all very good .tried to restart the van and realized no Service Engine Soon light come up . the instrument dash , guages etc. light up . no brake , SES , oread the manual I have and it appears as a possible blown PCM .?? tried a OBD1 test at the ALDL block and nothing comes up on dash . can't even get a code 12 on key ON position . can someone please help to to confirm if its a blown PCM or not ? self employed and this is the work van , had to temporarily use another truck Iown to keep afloat . LOL
2006-12-11 09:12:23 · 2 answers · asked by smokinsiggy 1 in Cars & Transportation ➔ Car Makes ➔ GMC
the dead short was caused when testing the inline switch I installed to temporary bypass the W/W module . didn't find power for the switch in the fuse box so went direct to battery to test the switch not thinking of my ignition being in ON position . when the switch was off it got hot and the lead wire connected to the Neg. post was stuck to the post. being an old school back yard mechanic doesn't quite work the same on these puterized cars . lol . I live @ 80k to the nearest wrecker so I'm trying the elimination process before the trip . from research and discussion with others it sounds like a PCM but unsure how to test. all fuses are good as mentioned before.
2006-12-11 17:28:32 · update #1
Not sure where your dead short was but if it was in the steering column you could have more trouble there. You are going to have to trace wire and such so unless your good with a dvom , test light and wiring dia. you may want to take it to a shop. I believe you have blown a power line to the dash but may have also blown the pcm too. You'll have to find the dash light trouble first because it could also be feeding the pcm line and if it burnt then no power will get to the pcm.Start by testing power and grounds to the dash do this with the dvom not a test light you could burn more stuff up. Then do the same to the pcm . You going to need a good wiring dia. Good luck hope I was able to shed some light on it for you
2006-12-11 12:06:18 · answer #1 · answered by Rudedude 4 · 0⤊ 0⤋
I think the ECM fuse is blown. It's should be a 10 amp...( red) fuse in the fuse block...they go before letting the ECM take a hit in most cases. If you have a 12 volt test light....connect to ground...turn on the key....check each fuse until you find the culprit. Good luck.
2006-12-11 23:41:09 · answer #2 · answered by Anonymous · 0⤊ 0⤋