Low beam headlight/AHL malfunction??

[KRAMCLASSIC]

So my passenger side low beam just went out recently. I automatically assumed it was just the bulb so I bought a set on Amazon and replaced them both. To my disappointment the same low beam is still not working. This also stopped working just right after I started getting adaptive headlight malfuction warnings as well. I'm not sure if these 2 issues are related but I couldn't find much on this topic. I'm hoping maybe someone here has experienced something similar and can offer me some help? thanks in advance.

[KRAMCLASSIC]

Any thoughts on this? Has anyone else experienced a Low beam headlight go out and replaced the bulb but still not fix the problem?

[88tuning.id]

i dont quite have this particular problem, but do you want to try to code out the AHL error?

[KRAMCLASSIC]

Originally Posted by 88tuning.id

i dont quite have this particular problem, but do you want to try to code out the AHL error?

So I swapped out the entire headlight assembly from the driver side on to the Passenger side, this means bulb, ballast, wiring harness, control module should all be in good working order correct? So I'm left with footwell control module I'm assuming? or possibly even just a simple fuse? I actually should have checked the fuses first of course but I didn't know where this was located so maybe I'll check there first.

If I do code out the AHL error, will that just disable the movement of the headlights? I'm assuming this won't make my headlight work all of a sudden.

[codinge90]

It's most likely the xenon control module if you changed the lowbeam bulbs and it's still not working. As for the Adaptive Headlight Malfunction, when you code it out you lose functionality of the adaptive lights. Headlights will work normal though

[KRAMCLASSIC]

Originally Posted by codinge90

It's most likely the xenon control module if you changed the lowbeam bulbs and it's still not working. As for the Adaptive Headlight Malfunction, when you code it out you lose functionality of the adaptive lights. Headlights will work normal though

Is this the same as the ballast? I googled this and the ballast came up which i've tested already and its in working order. I'm left with the footwell control module which I haven't had time to search for since I'm out of the country but will check this first when I get back.

[codinge90]

Originally Posted by KRAMCLASSIC

Is this the same as the ballast? I googled this and the ballast came up which i've tested already and its in working order. I'm left with the footwell control module which I haven't had time to search for since I'm out of the country but will check this first when I get back.

I would take a look at realoem and put you vin in. I know I'm e9x chassis there is a specific xenon module and there are other ballasts, not sure if it's different for e8x. I doubt it's the frm, if the frm is failing you'd notice more than just the low beam not working. Do you have access to a code reader? You could have a short circuit fault for the low beam which would mean the frm has stopped supplying power to the low beam, if that's the case the counter needs to be reset

[KRAMCLASSIC]

Originally Posted by codinge90

I would take a look at realoem and put you vin in. I know I'm e9x chassis there is a specific xenon module and there are other ballasts, not sure if it's different for e8x. I doubt it's the frm, if the frm is failing you'd notice more than just the low beam not working. Do you have access to a code reader? You could have a short circuit fault for the low beam which would mean the frm has stopped supplying power to the low beam, if that's the case the counter needs to be reset

Well I've tried 2 different ballast and the original still works as well, I do have a scanner so I'll run that first when I get back. I jumped to conclusions and started buying parts before really diagnosing it. thanks again for the input.

[Dackelone]

On USA cars the footwell module has an extended warranty. I think up to 12 years. ? Not 100% on how long it's for, but its been way extended.... but it's very common for the FW3 module to fail. Are you in the USA ? A new FW3 is your best bet. You will also have to code it to your car.

It sounds like its your footwell module wince you swapped the complete headlight units and they still don't work. There is an ECU under each xenon headlight. But like I said... it sounds like it's your footwell module.


As for how to figure out when you have a bad bulb... you can press and hold the BC(Board Computer) button down and read out the error code.

DIY: How to figure out which bulb is bad/out on your car?
https://www.1addicts.com/forums/show....php?t=1185634

[codinge90]

Frm is 10 year (from build date) 150,000 mile warranty

[KRAMCLASSIC]

Awesome, So I can take her to the dealer to get this sorted out, Sound like excellent news for me. Thanks for the tips everyone. I'm assuming the dealer shouldn't charge me a dime if this is under warranty, but I guess I'll find out soon enough.

[KRAMCLASSIC]

Originally Posted by Dackelone

On USA cars the footwell module has an extended warranty. I think up to 12 years. ? Not 100% on how long it's for, but its been way extended.... but it's very common for the FW3 module to fail. Are you in the USA ? A new FW3 is your best bet. You will also have to code it to your car.

It sounds like its your footwell module wince you swapped the complete headlight units and they still don't work. There is an ECU under each xenon headlight. But like I said... it sounds like it's your footwell module.


As for how to figure out when you have a bad bulb... you can press and hold the BC(Board Computer) button down and read out the error code.

DIY: How to figure out which bulb is bad/out on your car?
https://www.1addicts.com/forums/show....php?t=1185634

Hey Dackelone

thanks again for the tips, I dropped off my car to the dealer today and the service advisor told me that if the problem is my FRM Module they will replace it but they may not be able to save my tune (Dinan stage 3) is this correct? I would think they would be able to flash to stock and flash my tune back. This is getting pretty ridiculous all for just a headlight

[Dackelone]

Originally Posted by KRAMCLASSIC

Hey Dackelone

thanks again for the tips, I dropped off my car to the dealer today and the service advisor told me that if the problem is my FRM Module they will replace it but they may not be able to save my tune (Dinan stage 3) is this correct? I would think they would be able to flash to stock and flash my tune back. This is getting pretty ridiculous all for just a headlight

IF they replace your FRM module they have to code it for your car. The tech can do that the easy way by flashing/updating EVERY module in your car... of just the FRM module. Maybe talk to the tech.

Yeah, I would think your dealer could reflash your DINAN tune. But maybe they are not a DINA dealer ?

I wish you luck,
Dackel

[KRAMCLASSIC]

Originally Posted by Dackelone

IF they replace your FRM module they have to code it for your car. The tech can do that the easy way by flashing/updating EVERY module in your car... of just the FRM module. Maybe talk to the tech.

Yeah, I would think your dealer could reflash your DINAN tune. But maybe they are not a DINA dealer ?

I wish you luck,
Dackel

So I got my car back and according to the tech the output voltage to the low beam headlight that wasn't working was switched off?

I'm not sure how that happened but all they did was activate the output voltage and viola it was fixed. They still dinged me for the diagnostic fee but at least my headlights work now and they gave me a nice list of more crap I'm going to have to replace soon on my car

Anyway thanks for your help again Dackel and btw you have some awesome content on IG, i'm @which_mark

Enjoy the rest of your day everyone and until next time lol...

[Dackelone]

Originally Posted by KRAMCLASSIC

Anyway thanks for your help again Dackel and btw you have some awesome content on IG, i'm @which_mark

Enjoy the rest of your day everyone and until next time lol...

Hahahaa... Thanks for the Insta plug.

take care,
Dackel

[KRAMCLASSIC]

I Regret to update that my low beam malfunction has returned yet again. So I took apart my passenger side headlight again and inspected the ballast and there was a good amount of build up which I'm assuming was caused from moisture getting in. I swapped it out with a spare ballast I had which was in working condition before but still no good.

When I took my car to the dealer the first time my headlight went out, I asked them to check if my footwell control module was bad and they were able fix my headlight and confirmed my module was fine. I asked the service advisor what they did and all he could say was that they put power to the headlight? what the hell does that mean exactly? shouldn't this power up on its own once connected? does the ballast needed to be coded when you swap this? I've been driving around with one headlight for the last month and its kind of annoying. Bulb, ballast and modules are all good, what the hell gives??

[KRAMCLASSIC]

Originally Posted by codinge90

I would take a look at realoem and put you vin in. I know I'm e9x chassis there is a specific xenon module and there are other ballasts, not sure if it's different for e8x. I doubt it's the frm, if the frm is failing you'd notice more than just the low beam not working. Do you have access to a code reader? You could have a short circuit fault for the low beam which would mean the frm has stopped supplying power to the low beam, if that's the case the counter needs to be reset

Could you give me some tips on how to do this counter reset? I have a feeling this is what caused my low beam failure again.

[terced]

Originally Posted by KRAMCLASSIC

Could you give me some tips on how to do this counter reset? I have a feeling this is what caused my low beam failure again.

Interested to know this aswell, having a similar problem.

[mdk135i]

It's most likely the xenon control unit. Your situation sounds identical to mine. These cost $200-300 and require coding.

[M3nt4l]

Originally Posted by terced

Interested to know this aswell, having a similar problem.

This sounds like a short circuit issue. On the E Series there is a short circuit counter which,when a bulb blows, after so many ignition cycles it will stop sending power to that one bulb.

Use tool32 to reset the short circuit counter and it will send power to that bulb once again.

Any more information required just ask 👍🏽

[cooltechguide]

Yes, it is possible that the low beam issue and the adaptive headlight malfunction warnings are related. When the adaptive headlights are not functioning properly, it can affect the functionality of the low beam.

Here are a few steps you can take to troubleshoot the issue:

1. Check the fuse: Start by checking the fuse for the low beam headlights. If the fuse is blown, replace it and see if that resolves the issue.

2. Inspect the wiring: Inspect the wiring harness and connections for any signs of damage or loose connections. Make sure all the wires are securely connected.

3. Check the headlight control module: The adaptive headlight system may have a separate control module. If this module is faulty, it can cause both the low beam issue and the warning messages. Have the control module checked and replaced if necessary.

4. Get a diagnostic scan: If the above steps do not resolve the issue, it is recommended to have a diagnostic scan done on your vehicle. This will help identify any specific error codes related to the adaptive headlight system.

It is also worth mentioning that some vehicles have a separate fuse or relay for the adaptive headlights. Check your vehicle's owner's manual for specific information on fuse and relay locations.

If you are unable to resolve the issue on your own, it is recommended to take your vehicle to a qualified mechanic or dealership for further diagnosis and repair or check out this related articles: BMW Mini Headlight Problems.