adaptive headlights
 

so my adaptive headlights are really screwed. i have a 2005 4.8is last 7 of vin are LE83431. Anyways a few weeks ago i realized my driver side headlight wasn't working and the LED on the auto with was flashing when on. I didn't even think the issue was module related until i replaced the bulb and that didn't fix it. I have a schwaben bmw scan tool so i did a little code pulling. if i look into the LCM the only fault is ALC control module. If i go in manual activation mode the light turns on no issues. when i look in the AHL i get 2 faults: communication with stepper motor controller 1 disturb and signal fault to light switch center. If i use the scan tool to try and access the xenon headlight it says no communication available on both lights. previously the driver side light wouldn't come on at all but the passenger light would. the fog lights would also come because of the faults. Now i get nothing. when i turn it to auto, since it daylight, and switch on the fog lights the little fog light indicator light on the dash illuminates for less than a second an then turns off. Im really confused. Should i remove the bumper and switch the AHL from the left to the right side and see if the problem follows that module?

I have an 04 4.8is and passenger side wouldn't work on low or high beam. took the bumper off switched headlights and both lights worked only on the driver side. I had the led light on the switch blinking, fogs came on auto etc. after all the bs I took the glove out and swapped the ahl module and both lights work perfect now.

I'd swap that off and if you take the bumper off don't start taking the headlight apart until you plug the side not working into the side that's working first to see if it's something attached to the light.

Craziest thing. Took the bumber off and switched the headlights. The headlight workednon the other side. The Led in the cabin wasnt blinking so i figured lets try plugging jt back into the non working side and now its working. Could it have been as simple as a loose wiring harness. Im about to go back out and plug the other side in so they are both plugged in at the same time just to maks sure.

HA let me know. I had the same issue. When I took off the bumper I'd get the non working side working for a minute then it would go out. I kept thinking it was the harness, I was jiggling it etc until I finally discovered what it is.

Update, i tried pluggjng both headlights in at once and back to the same. Driver side not working again but no blinking led. So i unplugged the passenger side and tried again. The driver side head didnt turn on but after about 15 sec it kicked on. So i started thinking, what if i plug it in while its turned on and boom both side are working. I then cleared the codes and all the ahl module has no more codes. The lcm module still says that ahl fault but the led light isnt blinking. I turned the car off, pull the key and tried again. Boom both are working. Its been about 2 huors and im going to go out snd see if they will come in still. Im leaning toward buying the ahl. Does it need to be programed? You said its in the glove box?

It's behind the glove box. You gotta drop the glove box which is about 5 screws and it's in a slot behind it. Takes about 10 minutes to do. Your symptoms sound exactly the same as mine. I don't think it needs to be coded just the lcm does.

Lcm does if you change that is what I mean. I'm sure it's the module I'm talking about behind the glove box.

this is what your looking for behind the glove box. its in a slot with a tab that you pull out.


https://www.ebay.com/itm/BMW-X5-4-8i...8AAOSwHLNZQbid

Okay i ordered it today. Hopefully thats the issue, thanks for your help