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2002 Avy Bad Body Control Module?

jrmcgove

Full Member
Joined
Jan 1, 2012
Messages
68
Location
Wisconsin
A little history, I've been having issues with my power locks for a few years now. It used to be occasionally the doors would not unlock on the first try or only the driver's door would unlock and then after a few tries the other doors would finally unlock. The problem would go away for months at a time and then randomly reappear. Now for the last few months I can not get any door to unlock with power button except the driver's door. I have also been dealing with a parasitic draw on the battery that I have not been able to locate. One more minor thing but probably still related to BCM, the light on the dash the tells you when you have cruise control set no longer comes on but cruise control still works.

Yesterday I'm 4 hrs into a 5 hr drive. I stop at a gas station, lock doors, come back and have the usual problem unlocking. I start driving 20-30 yards or so and weird things start happening on the dash. Battery light on, no gauges working, ABS light on, seatbelt light on, air bag light on. Then everything seems to all of a sudden go back to normal. Shortly after I smell burning wires/electrical stuff. Smoke starts rolling from between the dash and the windshield on the driver's side and the security light is flashing. Now I'm freaking out. Thinking there might be something with the door locks, I push the button a few times. Probably a coincidence but the smoke stops and no more burning smell. I stopped and opened the hood, everything appeared normal. I decided to risk driving home the rest of the way. The security light stayed on the rest of the way. I also noticed when I rolled the window down, then back up once the dash lights dimmed when window got to the top and both turn signal indicators on the dash dimly lit up. Also noticed my 4x4 buttons no longer light up. Got home safely, parked the truck and unhooked the battery just in case.

Today I checked a few fuses related to the things I was noticing problems with and all were good. I hooked battery back up and started it. The security light no longer stays on, 4x4 lights on buttons are still out, still only the driver's door unlocks with power locks. Rolling the driver's window down/up sometimes makes the dash do weird things (ABS light comes on, seatbelt light, airbag light, gauges quit working). I do also have an aftermarket remote start/keyless entry system. The remote start no longer works (it was working before the smoke show yesterday). When I tried the remote start, the security light flashes and the park lights flash like an alarm function or something.

I don't see any obvious burnt or bare wires when looking up under the dash. I plan to do a more in depth search this weekend. Does this sound simply like a bad body control module? Does anyone have electrical diagrams for a 2002? I'm not sure where to start here other than looking for what was the source of the smoke, checking grounds, checking the rest of the fuses, and looking for bare wires.

Please help! Thank you
 
Look under fuse panel under hood for MICE CHEWED wires or maybe bad fuse panel
 
Yesterday I searched for any signs of burnt or bare wires. I could not find anything. I checked behind/below both fuse panels and the panel of wires in the left driver side foot well. Also checked for any suspicious areas in the wiring running down the frame along the brake lines since I recently replaced the brake lines. Nothing there either. I did find there seems to be an issue with the door lock relays. I switched them around in their sockets, after that the other 3 door locks started working and now the driver's door would not lock. It tries to lock and unlocks itself right away. I will be replacing both of those relays. I'm also wondering if there might be a short in the driver's door window/lock control buttons. It seems rolling down any window from the button set, especially the driver's window causes strange things to happen on the instrument cluster. That could be a problem in the BCM though too. I also found the ATC (active transfer case) fuse was blown. 4WD worked fine before this and I had not been doing anything with the 4WD when the smoke show occurred. I replaced the fuse, it did not blow again but now the Service 4WD light comes on. I did however just roll the driver's window down and up right before the smoke show.

Correction to part of my first post. My remote start/keyless entry system does still function normally. I forget it was wired to the hood switch to prevent starting the truck with the hood open and I had the hood open when I was testing it.

Does anyone know of any APP that allows access to the BCM or TCM using a bluetooth OBDII scanner?
 
Wait you have aftermarket alarm/start system?

Those things can cause all sorts of issues inthe long run even when everything was fine when first installed.
Check some threads way back really prevalent on 2002s.
 
UPDATE:

A bit delayed, but the problem turned out to be the TCCM was fried. You could actually see discoloration in the metal of the housing from the heat created when it "smoked". The large grounding strap from the back of the engine to the firewall was actually corroded/wore to the point it was about to break off. Many electronics are now working better with the new ground wire installed.
 
Nice to hear you got it fixed....I'm a firm believer that everything comes with smoke in it....Once it escapes it's best to get a new one ;D
 
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