Power window & radio issue

[hockeyman]

Not my car, but my Sergeant's 1999 Trans Am. Every once in a while, as he starts driving, the radio cuts off completely and the window switches fail to work all at the same time. A few moments later, the radio comes back on and everything is fine again. It only does this about once a day, and stays powered off for approx 5 minutes.

Now, I know everyone is going to say there's a short somewhere...I have already figured that out, BUT, if anyone has had that problem before, can they please direct me to where the problem was?

Do the radio wires and power window wires come from the same source in the fusebox?

Any help to this issue is much appreciated!

[CDNFB]

Re: Power window & radio issue

Sarge's car needs a new Body Control Module.

The power that supplies both the radio and the windows share a common power supply that originates in the Body Control Module. If you look at the back of the fuse panel you will see that the radio fuse and the big metal windows fuse share the same blue wire that traces behind and all the way across the dash to the body control module that is located just above the feet of the front passenger.

How do I know? Cause my 99 FB is doing the same thing and I've isolated it a timed relay on the circuit board of the BCM.

I'm too cheap to replace the BCM and I can't source a replacement relay, so I've built and am testing a wiring bypass.

[hockeyman]

Re: Power window & radio issue

Sarge's car needs a new Body Control Module.

The power that supplies both the radio and the windows share a common power supply that originates in the Body Control Module. If you look at the back of the fuse panel you will see that the radio fuse and the big metal windows fuse share the same blue wire that traces behind and all the way across the dash to the body control module that is located just above the feet of the front passenger.

How do I know? Cause my 99 FB is doing the same thing and I've isolated it a timed relay on the circuit board of the BCM.

I'm too cheap to replace the BCM and I can't source a replacement relay, so I've built and am testing a wiring bypass.

A_W_E_S_O_M_E! Thank you for the help! I'll order one for him tomorrow morning.:banana:

[mestupryan]

Re: Power window & radio issue

yeah wow, thanks. i have this exact same problem myself but haven't made a thread. ill look into getting the BCM.

one funny though, ive had this problem for a while, but lately its go to where when my radio and windows stop working, i can hit the door unlock button and they both start working briefly, lol. its a good show for anyone that rides with me

[bah]

Re: Power window & radio issue

yeah, bcm, i just hooked up a switch that taps into the cig lighter's power to the red wire going into the back of the stereo, if i am having problems i flip the switch and both work flawlessley

[mestupryan]

Re: Power window & radio issue

i ended up never gettting a new BCM, but the problem is coming back pretty bad. does anyone have a part # for the BCM? having a bit of trouble finding one.

[CDNFB]

Re: Power window & radio issue

Just call the parts dept at your local GM dealship and they will tell you the exact P/N of BCM for your car. Remember, you can't just buy the thing and then go home and install it. The GM dealership has to re-program the VATs key code into it before it will let your car start.

[ViperRider]

Re: Power window & radio issue

I'm having this same problem also. It's pretty bad. I can't use the radio anymore because it just shuts off all the time. I really don't have the money to get a new BCM. Is there any other way? Could there be a loose wire?

[ViperRider]

Re: Power window & radio issue

I was searching around and found this post.

http://ls1tech.com/forums/showthread.php?t=883334

I want to give this a try, but where exactly is the BCM? I opened the glove box and opened it all the way and behind it I just see a few wires and nothing else that looks like a box the can be removed. Is it down where the passengers feet would be?

[mestupryan]

Re: Power window & radio issue

I was searching around and found this post.

http://ls1tech.com/forums/showthread.php?t=883334

I want to give this a try, but where exactly is the BCM? I opened the glove box and opened it all the way and behind it I just see a few wires and nothing else that looks like a box the can be removed. Is it down where the passengers feet would be?

yeah im thinking so. im going to try this guide out soon, and ill make a nice write up with pictures when i do.

[v6mOtOrhEAdftOp]

Re: Power window & radio issue

the bcm is right behind the glove box, to the far right side. You have to get your hands underneath it and wiggle the piss out of it until it comes loose. I'll try to take pics later

[ViperRider]

Re: Power window & radio issue

the bcm is right behind the glove box, to the far right side. You have to get your hands underneath it and wiggle the piss out of it until it comes loose. I'll try to take pics later

I see, it hasn't been giving me any problems in the last week or so. But if it happens again I'm definitely going to try to fix this thing, it's an annoying problem.

[ViperRider]

Re: Power window & radio issue

Just to let anyone else know with this problem, today I painstakingly pulled out the BCM, soldered the board, and so far no problems. The bottom solder the guy at LS1 tech mentioned was the problem solder on my board also. It is a PITA to get the thing out, but I would rather deal with that then my damn windows/radio constantly going out.

[jsdomino]

Re: Power window & radio issue

The BCM is behind the glove box (take the glove box out). It is a black box about 4" x 5". It is hard to get at but not impossible.

You can buy one from Rock Auto for about $125. You can replace it yourself, but you have to reprogram it to your key.

Caution: You only get one shot at it, so if you screw it up you have p_ss_d away $125. That is why most people bring it to the dealer.

[ViperRider]

Re: Power window & radio issue

The BCM is behind the glove box (take the glove box out). It is a black box about 4" x 5". It is hard to get at but not impossible.

You can buy one from Rock Auto for about $125. You can replace it yourself, but you have to reprogram it to your key.

Caution: You only get one shot at it, so if you screw it up you have p_ss_d away $125. That is why most people bring it to the dealer.

It is hard, but not THAT hard. I have never soldered in my life before this, and I haven't had the radio shut off at all on me since I've done this.