headlight issues

[no6thgear]

Adaptive headlight stopped working, droopy eye.

Bought new headlight.

During install, notice ballast is very corroded on electrical connection.

New light installed, no error codes except for a ! Now. Do you guys think it's the ballast on bottom of headlight, or does it need to be coded?

[no6thgear]

Questions:

1. Has anyone on this forum ever had an active headlight error, replaced the headlight, then had it work perfectly after without coding?

Has anyone on this forum ever had a headlight not work without an active headlight error, and replaced the ballast?

[no6thgear]

Am I in the wrong forum? I've searched this and see a lot of headlight replacements but no one posts what happens after.

[Gray_Panther]

Originally Posted by no6thgear

Am I in the wrong forum? I've searched this and see a lot of headlight replacements but no one posts what happens after.

Which connection is the ballast corroded? Where it plugs into bulb or where it gets 12v from car?
If it is where it gets 12v from car i recommend unplugging ballast entirely, turn on low beams and measure to see if you are getting 12v into the ballast.
If you are getting 12v into where the ballast is supposed to plug in then i recommend replacing ballast. You can buy for a much less inexpensive price at theretrofitsource.com
If you arent getting 12v then i recommend looking at the footwell module. Get footwell module replaced and coded. Do research on footwell module cuz i dont know that much on it lol

[cheshirecat79]

Originally Posted by no6thgear

Questions:
1. Has anyone on this forum ever had an active headlight error, replaced the headlight, then had it work perfectly after without coding?

I've read results coming in both ways - that coding is required for a new AHL control and that a new AHL unit "just started working" after a couple of power cycles. From my experience, though, a new AHL controller will need to be VIN-matched to the vehicle for proper operation.

Has anyone on this forum ever had a headlight not work without an active headlight error, and replaced the ballast?

The AHL error is sort of a catch-all error that can cover different failures that pertain to the headlight assembly, one of those being the ballast.

There have been many people that have replaced the ballast only and have it work perfectly.

[no6thgear]

Thanks guys,

It is the metal control module in the bottom of the headlight held on with those two screws. I ordered a new one, replacing it this weekend. Hopefully that works.

[no6thgear]

Replaced ballast. Light still does not work. The passenger side one works though. So that rules out footwell module right?

If I replaced headlight and it needed coding....would only the angel eyes work and not the hid headlight?

[dcaron9999]

Somewhat related post ...

I have had one adaptive headlight malfunction warning light pop up on my 2011 135i. At the time of the event, I was driving the car hard at dusk (read: lapping). The malfunction light went away after I turned the engine off/on.

Car is still under warranty.

My dealership could not locate any DIAG errors or reproduce the issue, probably due to the fact that my Cobb PTF tune erases and clears the DTC's after any map changes or complete Cobb AP3 software removal from DME.

Any thoughts on the cause? Would vibration or hitting a large bump cause a warning light to pop on just like that?

[3002 tii]

Originally Posted by dcaron9999

Somewhat related post ...

I have had one adaptive headlight malfunction warning light pop up on my 2011 135i. At the time of the event, I was driving the car hard at dusk (read: lapping). The malfunction light went away after I turned the engine off/on.

Car is still under warranty.

My dealership could not locate any DIAG errors or reproduce the issue, probably due to the fact that my Cobb PTF tune erases and clears the DTC's after any map changes or complete Cobb AP3 software removal from DME.

Any thoughts on the cause? Would vibration or hitting a large bump cause a warning light to pop on just like that?

You'd have to hit a pretty large pothole to knock loose the headlight arm by the control arms. The only thing I can think of is the bulb isn't sitting tight. I'd check to see if the bulbs see loose.