'Intelligent lighting system inoperative' warning, and one xenon bulb is out

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SW18

MB Enthusiast
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Joined
Jul 7, 2016
Messages
1,785
Location
London
Car
Tesla Model Y (Formerly S212 E500)
Any thoughts or advice is welcome! I am hoping it is just that a bulb has gone, but I'd have expected a message that the bulb is gone rather than a message about the ILS. There's also a message that the Adaptive Lighting is inoperative. Funny enough the cornering lamps that are part of the ILS do still seem to be working. Thanks in advance for any ideas...
 
I'd change the failed xenon burner and see if the message goes away. No point worrying about what may not be an issue when there's an obvious fault / solution present.
 
Thanks! Tried swapping the bulbs and found that the bulb was not the problem, so a useful first check. Given that it was not the bulb that meant time to go and get plugged into Star. Turned out to be the controller unit (which was sitting in a puddle of water so showed up a failure in the headlight housing too). Result = a whole new headlamp, ouch :( Both headlamps do seem much brighter now though, so I think the controller must have been on its way out for a while.
 
Thanks for the update. Sounds like an expensive fix, but at least it's now sorted :thumb:
 
Thanks for the update. Sounds like an expensive fix, but at least it's now sorted :thumb:
I have the same problem. Water in the control unit and in the headlights. Is this not a faulty seal causing water to be in the headlights and the control unit? How do I put a claim to Mercedes UK that the seal should have been faulty or else where do all this water come from?
 
Yes, correct, this is ultimately due to a headlamp seal failure. As my car was over 6 years old at the time I did not look to MB for help or compensation. All diagnostic and repair work was done by my trusted independent.

Depending on the age of your car I guess you could approach MB for costs (especially if you’re still under warranty). To do that you’d have to take it up with your MB dealer, who may (or may not) be helpful. How old is your car and have you any remaining warranty? Good luck, anyway, and also welcome to the forum!


I have the same problem. Water in the control unit and in the headlights. Is this not a faulty seal causing water to be in the headlights and the control unit? How do I put a claim to Mercedes UK that the seal should have been faulty or else where do all this water come from?
 
Yes, correct, this is ultimately due to a headlamp seal failure. As my car was over 6 years old at the time I did not look to MB for help or compensation. All diagnostic and repair work was done by my trusted independent.

Depending on the age of your car I guess you could approach MB for costs (especially if you’re still under warranty). To do that you’d have to take it up with your MB dealer, who may (or may not) be helpful. How old is your car and have you any remaining warranty? Good luck, anyway, and also welcome to the forum!


Car is almost 4 years, so outside the 3 years warranty
 
Might be worth asking for MB contribution , nothing to lose
 
Let us know if you get any joy from MB, it’s always nice to hear of the few occasions where they do offer some goodwill.
 
Hi, SW18

Could You tell me which control unit You are talking about? I'm having the same issue with my ILS lamp in my W204 coupe. I've found that there are 3 modules connected to ILS, two of them are mounted on the bottom of the headlamp and one in the passenger foot area.

My problem started with moisture in the passenger headlamp. The headlamp was faulty? Did You try to change just the control unit?
 
Hi, SW18

Could You tell me which control unit You are talking about? I'm having the same issue with my ILS lamp in my W204 coupe. I've found that there are 3 modules connected to ILS, two of them are mounted on the bottom of the headlamp and one in the passenger foot area.

My problem started with moisture in the passenger headlamp. The headlamp was faulty? Did You try to change just the control unit?
Hi and welcome to the forum.

I didn’t do the work, my garage did, so am not sure which control unit was changed. I do know that it was under the headlamp. I might still have the part number somewhere on the invoice so will take a look. I had to replace the headlamp as well as indeed that was where the problem had started.
 
Thank You for the fast replay, I would be very grateful for the part number if possible. I tried switching one of the control units under the lamp between right and left headlamp but with no luck, passenger headlamp still malfunctions so that's not the problem. I didn't know that there is a second one when I took the whole front apart, I would switch both. There is one aluminium "colored" ballast and one big, plastic, squared control unit for LEDs (DRL, turn signals etc). I will be switching the third control unit / module that is in the passenger footwell tomorrow since StarDiagnosis pointed to that module but I personally don't think that's the issue. I only hope that it is not a mechanical problem with the headlamp but some electronic malfunction.

Do I understand right, switching the module would fix Your problem but You have changed the whole headlamp since that's what caused the issue?
 
Thank You for the fast replay, I would be very grateful for the part number if possible. I tried switching one of the control units under the lamp between right and left headlamp but with no luck, passenger headlamp still malfunctions so that's not the problem. I didn't know that there is a second one when I took the whole front apart, I would switch both. There is one aluminium "colored" ballast and one big, plastic, squared control unit for LEDs (DRL, turn signals etc). I will be switching the third control unit / module that is in the passenger footwell tomorrow since StarDiagnosis pointed to that module but I personally don't think that's the issue. I only hope that it is not a mechanical problem with the headlamp but some electronic malfunction.

Do I understand right, switching the module would fix Your problem but You have changed the whole headlamp since that's what caused the issue?
Yes, you understand right - the headlamp was working but leaking (was filling with water) and this destroyed the control unit. Both were replaced.

I checked the invoice and the parts were:
Headlamp left-side: A212 820 0939
Control unit A212 900 7804
 

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