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New thread in case this is helpful. I got the "adaptive high beam assist inoperative" (S212 2011 with Adaptive High Beam/cornering/etc.).
My passenger-side main beam went out. Bulb looks ok; sometimes low beam will come on, but only for 10-15 sec. There is no low or high either in the auto position or manual headlights on position. I've noted through a search that often this is the headlight controller under the headlight assembly, but it could also possibly be the physical shutter for the bixenon.
I believe that @konigstiger linked someone who dremeled out the shutter, but I can't find that now. I don't have a way to reprogram the module, either, but I assume that will need to be done afterwards, too.
For mine, it appears it was the controller. I was able to find one on Amazon that was same spec, etc., just no Hella or M-B branding for around $50 new. I took out fender liner (had a flat tire anyway), and then it's pretty easy to get to the T20s for the controller. Hooked controller up, and I have the beam. It's daytime, but will check to see if adaptive functions work without program (I doubt they will), but I can wait on that.
Even though I only dealt with the controller, I disconnected battery before working just in case.
New thread in case this is helpful. I got the "adaptive high beam assist inoperative" (S212 2011 with Adaptive High Beam/cornering/etc.).
My passenger-side main beam went out. Bulb looks ok; sometimes low beam will come on, but only for 10-15 sec. There is no low or high either in the auto position or manual headlights on position. I've noted through a search that often this is the headlight controller under the headlight assembly, but it could also possibly be the physical shutter for the bixenon.
I believe that @konigstiger linked someone who dremeled out the shutter, but I can't find that now. I don't have a way to reprogram the module, either, but I assume that will need to be done afterwards, too.
For mine, it appears it was the controller. I was able to find one on Amazon that was same spec, etc., just no Hella or M-B branding for around $50 new. I took out fender liner (had a flat tire anyway), and then it's pretty easy to get to the T20s for the controller. Hooked controller up, and I have the beam. It's daytime, but will check to see if adaptive functions work without program (I doubt they will), but I can wait on that.
Even though I only dealt with the controller, I disconnected battery before working just in case.
I had this same issue for the past month and finally tackled it this past weekend. In my case it was the actual shutter which was stuck and you could hear it binding upon start up and the light would shut itself off because it was stuck in high beam. I initially thought it was either the bulb or the ballast but unfortunately it was not, looks like you got away easy.
For anyone having this same issue as I explained you will most definitely need to open up your light and Dremel down the shutter to say yourself big $. My one piece of advice would be to take your time and use a oscillating tool to cut open the light and not a Dremel or heat gun, you will save yourself a lot of time and aggravation doing it this way.
Sawzall on the light housing? That would make me nervous! What did you use to reseal? I had to put in EVO projectors in my Saab, and working with the butyl putting things back in was a huge pain.
Maybe if Bi- Xenon headlight no need special programming because I doubt they have complex directional motors like ILS LED 640/641/642.
The ILS LED programming also involve power and voltage parameters to the LED headlight, not a simple handshake.
Maybe if Bi- Xenon headlight no need special programming because I doubt they have complex directional motors like ILS LED 640/641/642.
The ILS LED programming also involve power and voltage parameters to the LED headlight, not a simple handshake.
On the 2011, the bixenons have adaptive functions (cornering, etc.) just like the ILS LEDs. I imagine that's what the problem is. That said, the "auto" symbol on the cluster shows since I've replaced the controller, but the hi and lo are out of sync ("resting" position for the replaced side is now high beam.)
So, a new wrinkle. Indy (which I've never used before) says that the left/main headlight module can't communicate with the right because of corrosion and I need a new assembly. $3k. Even though the right controller was just replaced and, after doing so, the system looks to work fine (just is reversed on hi/lo beam). @konigstiger et al, any thoughts? I'm happy to take the wheel off and look for water/corrosion in the wiring of the left, but literally all I asked them to do was reprogram this and do diff service (they said there was a little metal in the back one, so I need to replace all). Very frustrating, and hard to find indys who are honest (they've kept my car for a week with no updates).
Check left control module to see if corrosion is isolated to module or has affected headlamp receptacle, if all seems fine with both module & headlamp move on to front SAM. If all looks good @ SAM you can either get a second opinion or have them replace headlamp. Provide VIN I’ll pull part #.
Last edited by konigstiger; 10-17-2022 at 06:12 PM.
This was the frustrating part. Replacing the right side one got that light working again, and the adaptive part (servo motor) is fine, as is the function of the adaptive highbeam sensor...it's just giving me the wrong beam at the wrong time. No error message anymore, either.
Check left control module to see if corrosion is isolated to module or has affected headlamp receptacle, if all seems fine with both module & headlamp move on to front SAM. If all looks good @ SAM you can either get a second opinion or have them replace headlamp. Provide VIN I’ll pull part #.
@konigstiger thanks again. I'll do as you say. Weirdly, the passenger side module just died: no water in the headlamp or corrosion on assembly or the module. Just died. The indy said there was corrosion in this one, so we'll see... But $3k part + install for the headlight made me mad! No way it's that much labor. I'm hoping it's not the SAM...that will be a pain. I think I should have part numbers in my WIS-EPC copy. Thanks so much!
Sorry to bump an old thread, but now that I have an iCarSoft: I can see the front SAM. The SAM sees the left xenon assembly but not the right. Maybe I misunderstood the diagnosis (and they wrote it up wrong), but the headlight assemblies communicate with the SAM, not each other, correct? In another module (maybe body control?), the RH xenon assembly is listed but says it's not installed. Either way, when I try to do diagnostics on the LH one, it checks out fine, but the RH one is no dice. It does function, just backwards.
I'm going to swap the modules and see if that makes a difference. Could be a bad one, I guess, but looking again at the report from the indy, he says the wiring looks fine. Thanks again for the help of everyone in here, especially @konigstiger . Really appreciate this community.
The SAM sees the left xenon assembly but not the right. When I try to do diagnostics on the LH one, it checks out fine, but the RH one is no dice. It does function, just backwards.
May need initial startup, see attachments.
Last edited by konigstiger; 04-04-2023 at 12:11 PM.
@konigstiger not sure why I'm not getting notifications for posts, but thanks again, as always.
So seems like something that an aftermarket MB scanner might not be able to do? Am planning switching them around this weekend if I can get some time.
We have a great local Swedish garage that goes the extra mile, but unfortunately Birmingham AL doesn't seem to have anyone similar for Benz. I'm happy (and would prefer) to pay for this stuff, but...
10-03-2022, 11:57 AM
