HELP! Lights problems
 

Hello all, I'm an old member with a new profile and need some help. I think it's a small problem appearing major. I have done a search on the forums but didn't find anything.

2002 X5 4.6IS
140,000km

The car has been sitting for a while, so I put in a new battery and it fired right up and all warning lights cleared as they should. But my lights are all crazy acting.

The headlights are on, except for one low beam bulb. I can not turn the highbeams off. The signals and flashers do not work. In the rear, the taillights are lit up, and one reverse light is on all the time. One interior light in the rear is on all the time.

I checked all fuses, they are fine. I have no idea where to begin chasing this problem. I'm thinking a ground or a lighting module ???!!!
I've done a fair amount of work to this car so not afraid to do what I need, just looking for some support.

Trying to sell the car as I've just bought a Porsche, and want to rectify this issue before it goes for Sale.


Thanks for any guidance.

Possibly a gremlin in the programming somewhere. Have you tried disconnecting the battery and reconnecting again. Sometimes a simple reboot can solve a lot of unnecessary pain and troubleshooting.

:iagree:

Yes I have disconnected, let sit and reconnected the battery three times, with the same symptoms.

Any other directions as to where to start?

Did it only happen since the new battery....
Since you said it's been sitting for awhile, it sounds like you might not remeber.
Sounds like a LCM on it's way south or has gone south already

Mice?

Water ingress to the LKM?

In the E39 (5-series) world, this is known as LCM chip shorting out.
The chip in E39 LCM is Infineon type, BTS426L1 to be exact.
Do a google search on this chip, not sure if it is applicable to E53, but a google search is free...LOL.

Definitely in the right direction. Read through a few different posts regarding the LCM on this and other forums on the e53 and e39 and it sounds exactly like it!
This weekend i'll pull it and see if In fact theres some moisture down there. The car did sit outside and has barely been moved for a year or more.

I'm reading that a replacement LCM has to be programmed to the VIN. can this be done on the bench or does it have to be installed first?

Thanks guys, I knew someone would point me in the right direction

Installed first.
But not only programmed to VIN, you need to program to match mileage as well.