Body control module??

2002 GT - starts fine except that I have no speedometer, tach, gauges radio, AC , ect. Then after a short time (couple seconds sometimes, couple minutes others) everything comes on. A mechanic friend looked at it and redid the grounds, but it is still acting up. Though it seems less frequent. He said I may need a new BCM or just to reprogram the one I have. If I take it to a dealership, I suspect that they will just want to replace it. Any thoughts on the chances that this is the only option?? Is this something I can replace myself? I had read elsewhere that you may need to program the module?? Thanks

Welcome to AF!!

Go to a wrecking yard and find a BCM for your particular model and options. If you have keyless entry make sure that the one you pick up has that too or it won't work. You can install it yourself as it should be as simple as plug and play. You may want to find the one in your car and get the module number from it before looking for another one. This will avoid confusion when you get to the wrecking yard. If no local yards have one try car-part.com.

BCM causing your problems? I don't know about that. What are your other indicators listed as etc? Sounds more like a problem related to the ignition switch or a wiring problem.

BTW - If you get a new BCM it will require programming at a GM dealer.

the other things that aren't working are - the auto lights don't come on, but the lights will work in manual, no warning lights, no power windows/locks/sunroof, interior lights, maybe more but that is all I know for sure....I can't get it to do it right now.

So is anyone sure about the programming part?

the other things that aren't working are - the auto lights don't come on, but the lights will work in manual, no warning lights, no power windows/locks/sunroof, interior lights, maybe more but that is all I know for sure....I can't get it to do it right now.

So is anyone sure about the programming part?

The BCM is programmed to the options in your car. A new one off the shelf will require programming. As Lynn mentioned the other option is to get one from a salvage yard but it must match your year and model Grand Am to the T.

Have you checked all the fuses associated with the BCM and secondary ignition circuits? Although it could be a BCM module your symptoms sounds like a combination of problems. Some match a possible ignition switch and some match a possible defective BCM such as interior lighting and no power door locks. Other symptoms such as auto light/DRL, HVAC and Instrument Panel (IP) lighting sound more like the ignition switch. Also, check the connectors at the BCM and make sure they are on properly and tight. I'd check to make sure the BCM is getting 12 volts before deciding it is the problem.

YA my GT has been giving me some fits like that sometimes. Not recently, but I'm pretty sure my Bcm is bad.
Mainly because when I run any diagnostics, it can not communicate with the bcm. And my svs lights on again, go figure :screwy: Luckily I hav one that matches to the T that I'm hoping it'll fix my woess.

But Bob and GTP Dad are right about programing of the "new" bcm by a dealer.
And if you go messing with the Bcm make sure you are static free, just touch something metal before touching the bcm, static can toast'm :grinyes:

Good Luck amw8579 !