Hello everyone,

Since I've owned this car, I've had so many electrical issues with it I've lost count. I'm not sure where to start in diagnosing all of these problems, but I think it may be the BCM, or maybe I'm completely off, however I don't think it's a coincidence that these are all separate issues.

Nearly all interior lighting will erratically flicker/blink
HVAC fan control can never be on a number, I have to hold the dial between a number (1 1/2, 2 1/2, etc) for the fan to kick on
Instrument cluster constantly shuts off along with head unit and turns back on within a few minutes
Random ABS lights
Service vehicle soon light turns on when I pull the light switch out to turn the headlights on in the rain
Key fobs won't work unless I basically put the key on the door, no distance

Could this be a bad bcm? Bad ground somewhere? Please help, I am lost when it comes to electricity.

John

 

Sounds like it could be a large list of gremlins. Best course of action is probably take 1 or 2 problems and start tracing them down. It could be very possible you have a ground situation that is having issues (like corroded and barely making contact triggering a multitude of things). If you are uncomfortable diagnosing these topics, you may want to consider locating a reputable shop OR even a good dealership (keep in mind, the dealership repair services should have all the GM information and tools required to do the job).

 

I agree that it sounds like a bad ground, and/or it could be the ignition switch. The switch making poor contact in the On position would not provide enough power to start headlights or HVAC blower properly. I had an HVAC issue where the blower would randomly shut off and I could turn it to 5 and it would run and then down to 1 or 2. Completely fixed by a new ignition switch. But I didn't have those issues of other systems shutting off. And I didn't have any issues like that before my BCM blew out, so I can't confirm that is your cause. The used one I put in back in May hasn't had any problems either.

That said, cleaning up your grounds is the easiest first step. The first is on the core support above the driver headlight. I believe there is another hidden under the air filter box that caused problems for someone. Several good posts about that here somewhere.

 

Thanks Glen. I went ahead and replaced the ignition switch, no changes there. I will have to go look around at the grounds (and find them all)