Xenon headlights, sometimes works, sometimes doesn't

lemonpark · 02-17-2017, 07:51 PM

Hey guys,

I've been having this problem for a while now and will try to go through all the steps I've been through and what actually is happening.

So I had my headlights blacked out and LED RGB angel eyes put in a while ago. Everything was perfect until one day I went to wash my car and then after that the driver side low beam went out, went and got all new bulbs and ballasts and it worked again. Now, my battery was getting a bit old (always reset the date and time) and then my passenger side low beam would just sometimes not work, about 50% of the time it wouldn't turn on. I then replaced my battery and both low beams worked again for about 1-2 months. Now my driver side is working but my passenger side isn't. I really can't get to the bottom of this problem because sometimes both sides will light up, sometimes only passenger side, sometimes only the driver side and sometimes none at all.

For example, last night I noticed that only my passenger side was on so I went from "auto" in the light controls to "0" then to "auto" again and none of the low beams would come on. Restart my car and then only the passenger side came on again.

What could this be? I don't think it's either bulbs or ballasts, might be something to do with the wiring or the FRM? And is the "light control" module different to a ballast? I read sometime about another small control module being on the side of the headlights.

Thank you if you've read this far and have any input to give.

kisarci · 02-19-2017, 09:30 PM

To answer your last question, if you have adaptive headlights, yes there is an adaptive headlight module on the side which can cause your headlight to act funny (AKA AHL module or SMC II module). My lights were randomly coming on and off like you and after replacing the AHL module, it worked well again. If you buy the AHL module new, just remember you have to have it coded or else they will move all over the place. If you buy one used, make sure it is the correct side, driver's or passenger's, and then it will not need to be coded. New ones you can find for around $150 and used ones i've seen go from 80-100. I hope you figure this out. Headlight problems are so annoying... I've been through so much myself after getting them custom done with black housing and LED RGB as well

I hope I provided some kind of help to you.

02-17-2017, 07:51 PM	#1
lemonpark Captain 61 Rep 610 Posts Drives: '08 335i E92 Join Date: May 2014 Location: Melbourne iTrader: (0)	Xenon headlights, sometimes works, sometimes doesn't Hey guys, I've been having this problem for a while now and will try to go through all the steps I've been through and what actually is happening. So I had my headlights blacked out and LED RGB angel eyes put in a while ago. Everything was perfect until one day I went to wash my car and then after that the driver side low beam went out, went and got all new bulbs and ballasts and it worked again. Now, my battery was getting a bit old (always reset the date and time) and then my passenger side low beam would just sometimes not work, about 50% of the time it wouldn't turn on. I then replaced my battery and both low beams worked again for about 1-2 months. Now my driver side is working but my passenger side isn't. I really can't get to the bottom of this problem because sometimes both sides will light up, sometimes only passenger side, sometimes only the driver side and sometimes none at all. For example, last night I noticed that only my passenger side was on so I went from "auto" in the light controls to "0" then to "auto" again and none of the low beams would come on. Restart my car and then only the passenger side came on again. What could this be? I don't think it's either bulbs or ballasts, might be something to do with the wiring or the FRM? And is the "light control" module different to a ballast? I read sometime about another small control module being on the side of the headlights. Thank you if you've read this far and have any input to give. __________________ JB4 G5 ISO \| BMS Backend Flash \| Alpina B3 TCU Flash \| AR Design Catless DP \| BMS DCI \| ER CP \| Turbosmart Race Port BOV \| Muffler Delete \| H&R Sport Springs \| BMS Cowl \| BMW Performance Alcantara Wheel \| M3 DCT Paddles \| Muse Concept and Design Interior \| 19" GTC-CX \| M3 Lip Spoiler \| Zieg CF Rear Diffuser \| Flow Designs Front Lip \| Black Grill \| RGB LED Angel Eyes \| 8000K HID \|
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02-19-2017, 09:30 PM	#2
kisarci Lieutenant 67 Rep 435 Posts Drives: 2007 335i Join Date: Dec 2014 Location: Long Island, NY iTrader: (0)	To answer your last question, if you have adaptive headlights, yes there is an adaptive headlight module on the side which can cause your headlight to act funny (AKA AHL module or SMC II module). My lights were randomly coming on and off like you and after replacing the AHL module, it worked well again. If you buy the AHL module new, just remember you have to have it coded or else they will move all over the place. If you buy one used, make sure it is the correct side, driver's or passenger's, and then it will not need to be coded. New ones you can find for around $150 and used ones i've seen go from 80-100. I hope you figure this out. Headlight problems are so annoying... I've been through so much myself after getting them custom done with black housing and LED RGB as well I hope I provided some kind of help to you. __________________ 07 335i e92
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