• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

Body Control Module

L

Larpi

New member
I have a 2008 GXP. I was rear-ended and pushed into the car in front of me. Immediately after the accident, my key fob no longer worked, a few dash lights stopped working, and my washer pump quit working.

The dealer ran a diagnostic check for the insurance company and said that my BCM was malfunctioning causing all the issues. The tech at GM said that the accident did not cause the problem because he replaces them on the Grand Prix all the time. The tech said that it is a common faulty part.

I called another GM dealer, and they said that you cannot rule out the accident as the cause of the problem with the BCM.

Has anyone else had problems with their BCM on a 2005 to 2008 model Grand Prix? If this is such a common occurrence, why is there not a recall?
 


I haven't heard of them not working for no reason. Or at least the symptoms your getting.. I bet some wires were crushed from accident
 
I am sorry to hear of your accident. I am glad to hear that you are okay! I have researched your issue regarding the BCM and have found no information about a recall. It sounds as though the problem may be due to the accident itself. Keep us posted. If you have any further questions, please feel free to message me.

Louis
GM Customer Service
 
These cars the dash lights are very common to go, usually in the radio, climate control and window switches. There is no doubt in my mind the accident caused these lights to go and a faulty BCM would not cause this issue unless all back light lights on the speedometer, and what I mentioned above all stopped lighting up. My 03 sunfire I had a few years ago had the odometer light burn out after a 50 km/h impact.

The lights are all soldered in these units so it's on the insurances plate to replace whatever parts have the lights burnt out inside them. If they end up not doing so even after a fight with them they can be replaced by anyone with good soldering skills.

The remote...A Bad BCM could cause this issue with keyless not working, but it's common in these remotes for the battery clip to become detached from the circuit board due to bad solder joints. The remote hitting on the dash in the crash could have pushed this over the edge and cracked the solder. It's held in place by three different places by solder, open it up and check these.

Do you have a spare remote? if so does that one work the car? and does your power locks work with the switch?

The BCM controls the power locks, The keyless entry reciever is a box in the back of the car between the two speakers that listens for the remote commands and tells the BCM what lock/unlock actions to do when a button on the remote is pressed. If your tire pressure system is working then the link between the keyless entry reciever and the BCM is good as the keyless entry reciever also communicates with the tire pressure sensors.

And the windshield washer motor...these are pretty close to the bumper and stuff usually, So I would say the accident probably caused this and deserves a closer look for severed wires.

In any case the exterior and interior lighting all go through the BCM, So if you got any wires pinched in a wreck and shorted to ground this could very well mess up the BCM. This could be why the diagnostic determined the BCM was malfunctioning as well. but replacing the BCM alone will not fix the sections of interior lighting that are not working, but could be the culprit for the other issues.

Once this thread gets enough responses I would show this to the insurance company as well, I know the car inside and out electrically.
 
Thank you for all of the feedback. Neither fob works. I have to lock the car with the lock button on the door, and unlock the car with a key. I replaced the batteries, and the solder points look good.

The lights that went out are the temperature down light and the heated seat light on both sides of the dual climate controls.

The washer pump works if you hook a battery to it, but not when it is hooked up to the car.

I am contacting the insurance company tomorrow.
 
I have a 05 GXP and I have the exact same lights out on my climate control. Everything else works fine except the HUD which I need to fix the spring. Good luck.
 


This is interesting - I have only had my GXP for a week and already discovered that I may have an issue with the BCM. My issue is the low beam headlights no always working - sometimes they come on automatically and then shut off, other times they will no turn on at all - even when turned on manually. My local GM dealer said this is a BCM problem that involves the computer controlled daylight sensor relay and PIC. I have no had any error codes pulled from the unit to confirm but it seems possible. Another issue that may be related is the speakers/amp sounds like it is always on even when everything else is turned off - there is 'white noise' from the speakers???

I think this is an issue on more GXP's than GM will admit to - because the more I research it, the more issues relate back to the BCM. A new BCM and programming will set me back almost $400 which isn't covered by the 30-day/1000-mile warranty. I am not happy about this at all.

If anyone can provide some feedback or a possible method of resolution, I would like to know. THANKS!
 
This is interesting - I have only had my GXP for a week and already discovered that I may have an issue with the BCM. My issue is the low beam headlights no always working - sometimes they come on automatically and then shut off, other times they will no turn on at all - even when turned on manually. My local GM dealer said this is a BCM problem that involves the computer controlled daylight sensor relay and PIC. I have no had any error codes pulled from the unit to confirm but it seems possible. Another issue that may be related is the speakers/amp sounds like it is always on even when everything else is turned off - there is 'white noise' from the speakers???

I think this is an issue on more GXP's than GM will admit to - because the more I research it, the more issues relate back to the BCM. A new BCM and programming will set me back almost $400 which isn't covered by the 30-day/1000-mile warranty. I am not happy about this at all.

If anyone can provide some feedback or a possible method of resolution, I would like to know. THANKS!
Click to expand...

First off theres an HDM solid state module in your under the hood fuse panel (looks just like a relay) its labeled and they are known to go bad. they control drl/headlight function. I'm sure that's your problem.

your other issue with the radio.. the monsoon amp stays on after you get out to allow the door chime to function it is normal. Any other questions just ask. :beer:

Sent from my SPH-L710 using Tapatalk 2
 
rperry435 said:
First off theres an HDM solid state module in your under the hood fuse panel (looks just like a relay) its labeled and they are known to go bad. they control drl/headlight function. I'm sure that's your problem.

your other issue with the radio.. the monsoon amp stays on after you get out to allow the door chime to function it is normal. Any other questions just ask. :beer:

Sent from my SPH-L710 using Tapatalk 2
Click to expand...

If you are right about my headlight issue being an HDM solid state module - that'd be great, but everything is pointing to the BCM. I cannot identify a relay for the low beam headlights - there are only (4) 10amp fuses for headlights under the hood. Any feedback on which one it is would be greatly appreciated! Thanks.
 
It's there. And labeled. Relays are gray and the hdm is black. I can go take a picture of it. If you still can't find it.

Sent from my SPH-L710 using Tapatalk 2
 
rperry435 said:
It's there. And labeled. Relays are gray and the hdm is black. I can go take a picture of it. If you still can't find it.

Sent from my SPH-L710 using Tapatalk 2
Click to expand...


Okay, attached is a picture of the fuse/relay block under the hood with an arrow to the HDM, please confirm this is correct, thanks!

Fuse Block HDM.jpg
 


GMCustomerService said:
I am sorry to hear of your accident. I am glad to hear that you are okay! I have researched your issue regarding the BCM and have found no information about a recall. It sounds as though the problem may be due to the accident itself. Keep us posted. If you have any further questions, please feel free to message me.

Louis
GM Customer Service
Click to expand...

......... oh, I don't know maybe someone checked.......
 
You must log in or register to reply here.
Back
Top