Thread: Electrical issue????????

My car started running like crap again out of nowhere. First I noticed the loss of power then noticed high knock and misfires again. Then it just got weird. My gauges started to go crazy cutting off and on then the power to the gauges stopped and then came back on. The abs, traction, security, and all the rest of the warnings kept going off. It started making a horrible noise so I pulled over and opened the hood to see what it was. Everything was turning on and off. The throttle body was making noises, the relays for everything was activating on and off. The car died and will not start back up. But the weird thing, all the relays, throttle body and tests kept running even with the keys out of the ignition. The battery is newer and has no corrosion. All the grounds are good.

Could this be the ECM??? Or the BCM???? I have the battery completely unhooked right not to try and reset everything. Any suggestions. I'm stuck in a cvs parking lot now.

Rick all those electrical issues at once sounds like a possible charging issue. As you know once a vehicle is started the car runs off the alternator. If the alternator doesn't charge properly and the voltage drops all sorts of odd things can start happening.

If I can get it started I will check the alternator. I didn't get a charging system failure notice before it died though. I've been doing some searching around and didn't find much on this issue. The stuff that came close was either an ECM or throttle body. It's weird. When the car is off and key out of the ignition the third brake light stayed on and just the engine light.

I can not get it started. I pulled a code and it is P0069 map sensor. Since the map sensor is a brand new AC Delco I am leaning torwards a bad PCM. Any other suggestions?

if you got a spare comp g pcm give it a shot.

I pulled the Pontiac enhanced obdII codes and got the following. U1064 loss of communication to the BCM, P0564 cruise control switch, and the P0069 Map sensor. Again some weird shiznit happening. I noticed with the key out of the ignition and the door open I can still roll up and down the windows, the radio lights were still on, the engine light on the dash is still illuminated. This stuff should all go off with the key out and door open.

Could it it be a bad BCM causing everything to stay on? ignition switch, or wiring????

dont a bad ignition harness do this kinda wacky stuff?

Originally Posted by Scottydoggs

dont a bad ignition harness do this kinda wacky stuff?

I'm not sure. I don't know much about electrical or how to test the harness. I have read that some have replaced the ignition but sometimes that did or did not work.

no idea on testing it either, most shot gun one in with things like that when one or more issues are a common fault when its bad.

the radio staying on iirc is one.

Is this the part you are talking about? https://jet.com/product/detail/ee362...a:2&code=PLA15

never did a 04 up one, but it looks right and the description is spot on.

you might find that cheaper at rockauto or ebay.

Thanks. I'll check it out. Worth a try

if you have a tuner flash your last known file to it. hp might be a issue cause it will want you to unlock the new pcm vin i think.

and you likely needed to do a security learn due to a different osid # in the new pcm.

I programmed the correct vin and did a write calibration. Everything seems fine so far. Runs good again. I just unlocked the whole year and model. Used up all my credits but I don't plan on using it for another vehicle.

Thanks for the help