Hi everyone. Great page, lots of good info. I just bought my first MC, a 2001 LS and I need a little help please. I have no interior lights (dome,doors, or footwell) when I either open the door or use the headlamp switch. The VATS will not shut off with the use of the key in the door lock either. I do not have keyless entry or an aftermarket alarm. It doesn't seem to be fuses as the trunk and glovebox lights do come on. Is this the BCM? If it is, is this an expensive fix? Thanks in advance.

 

I did a bit of research on this. From what I have read and what I have experienced in the shop, if all fuses are good and nothing else seems to be obviously broken or damaged, I would suspect the BCM to be the cause.

As far as replacing the BCM, I can tell you that in a dealership, you should expect to see a charge of between $450-550 depending on your area and local labor rates. This does not include the initial diag on the car.

Good luck and let us know how it turns out.

 

Will this produce DTC's NYCRISS?

If so, what are they?

 

Yes it will. Generally, the DTC will be a U code... or loss of communication. I will look up the specific BCM codes for you...

 

Ok the most common codes would be U codes such as U1000, U1050... these are loss of communication codes and would suggest that the BCM needs to be either reprogrammed (which is not easy since there is no communication) or replaced. The other DTC's that the BCM could trip are known as B codes (B for body). A B code is more desirable because communication is established and a reprogram/calibration can be performed before condemning the BCM.

That's all well and good but lets not make the most common mistake... do not overlook the obvious. It is quite possible that a bad door switch is the cause. The BCM works off a signal from the door switch telling it that a door has been opened and to power up the interior lighting system and all of its functions such as theater effects. Always exhaust the simple possibilities before looking into a computer related malfunction.

 

Thank you very much NYCRISS. I should have mentioned that the lights don't work when opening either door. Thanks again.

 

what fuses have you checked? on the drivers side or the pass. side?

I went all over my car right after i got it for this smae thng I finally found out the fuse to the dome, and map lights is actually on the pass side of the car in the fuse pannel in the door jamb.

I have met some folks that never knew thier car had a fuse pannel there. i would not have if it wasent for this.

So i would change the fuse even if it looks good or test good with a light i have see those blades not work even when testing good.

So it is worth the shot.

Also if you do find that the bcm is the issue get the after market tuned computer for the car they are cheaper and easy to install. The computers on these cars are not hard to get to no dificult to replace or unplug

 

Mickey, I checked the fuse block on the passenger side; fuses were good as other lights (trunk and glove box) on the same circuits operate no problem.

I am confused though. I used an OBD2 tester, and no codes showed up. (I did not have a "Check Engine" light) I then used a test light on the socket for one of the footwell lights and had a bright light on one side and a dim light on the other. I tried using the headlight switch to manually turn the interior lights on and off with no changes to the test light. Is this just a bad ground?

I will go to the dealer when time and $ permit, and I'll post the results here. Thanks Guys!

 

yes this could be a bad goround have you done any work on the inside of the doors or anythign that might have been in the area of the ground?

Also as much as this might sound funny try going to a bone yard and getting adiffrent light switch for your car see if the switch went bad on you.

if you do this and all is good you can go get a new one and put the wroking one in the tool box as a tester.

Good luck on this one bud even the manuals i have (factory set) say the same thing check switch and check ground and check fuses