Hi all,
My 2001 monte with the 3.4 engine is behaving in a bad way. Recently when driving the service traction control light comes on, turning the tc off, battery light comes on and the turn signals quit working and then it goes back to normal all by itself during the same trip with the exception of the traction control not coming back on.

Now, when attempting to start it multiple things light up on the dash and flash in a very erratic way. The airbag, battery, abs, brake lights and also the tach starts jumping. I also hear some type of whine but can't tell what it is. Maybe the fuel pump still trying to spin up? It does not even attempt to actually turn over.

When it does start normally everything seems ok except I can still hear a very faint steady whine that sounds electrical not mechanical. It doesnt seem to come from the engine compartment though. Almost like the middle of the car and not coming from the speakers that I can tell.

I'm going to check all the electrical connections I can, especially the bcm connections but has anyone had similar problems and what was the fix?

Thanks much for any help!!!

 

Electrical issues are the worst! My 2002 SS is having strange issues as well. The cruise light comes on by itself along with the A/C. While this happens the auto dimming mirror doesn't work and the overhead DIC doesn't display anything. The fan motor for the a/c come on and off when it wants to as well. I took her to the dealer today and they are totally stumped. They said they had three techs look at it and they have no idea. I think my problem might be the BCM as well. They said they would check the grounds and wires. My problems mainly happens when I start it. My gauges also reset when driving. I will let you know what they say and maybe it will help you. Maybe another member will chime in with some input. I hope we can figure this out!

 

It has to be the BCM. They are known for going bad in all of the 6th Gens. I have been fortunate enough to not have this happen to mine, but from what I hear, when it goes bad, the car goes berserk with the electrics. The BCM is in the dash, on the left near the Gauge Cluster. That might be the whine you're hearing.. The only way to fix that is to replace and reprogram the BCM for your car. Hopefully it's not that and it's just wiring. Good Luck!

 

Mine was doing the same things, brought it to the dealer and had the bcm replaced, haven't had an issue since. Mine got really bad and wouldn't even start or anything before I had it fixed. Good luck!

 

So after taking mine to the dealer and having them check it out they said it was the ignition switch. I replaced it and haven't had an issue since thank goodness.

 

Thanks for the replies. I cleaned the electrical connectors and ground connections under the hood and cleaned the bcm/pcm connections also. Sometime the car starts normally, other times it starts but various lights come on, air bag, traction control, brake and sometimes it wont start/turn over.

Does anyone know if the bcm can be tested if I remove it to save a tow?

Would a salvage yard bcm work assuming its from the same generation monte with the same engine and tranny and similar options?

Thanks for any help offered!

 

I recently sold my 01 to my son and now it's in the shop in another state because it would not start and with the key off the gauges were moving around. It sounds like the BCM. The BCM's sound like a pita on these. I have a problem with mine too (doors won't unlock with remote).

 

I was originally thinking it might be the ignition, leaving the key on for 10 minutes would get it started but then the problems with all the lights coming on started so I was thinking BCM or wiring.
I found a used BCM from a 2000 for only 20 dollars. I wondering if its possible to just swap them out. All I want to do is get the car starting reliably. If it would at least do this with the salvage yard part I would then order a new BCM and have the shop program it. I figure about a 300 dollar savings if this is possible.

 

From what I heard you can't just stick another one in there because the dealer has to program it. I'm wondering if I get mine replaced and keep the old one for a spare I should be able to plug it in since it was programed to work with the car.

 

In the how to section for 6th generation cars there is a youtube link describing the relearn process, it was posted by superrod29. Its for a 2004 hummer but I'm thinking it probably is valid for other GM's also.