Izrud

Hello All,

I have a sports package e350 4matic and I am having some issues with the driver's side fog light.

When I put my lights on Auto, only the passenger's fog light turns on. When I turn the fog lights manually on, both of them work. I am baffled as to why this might be - any ideas?

cetialpha5

Do you have bi-xenons? They don't normally come on when it's on auto. With bi-xenons, they came with active curve illumination which turned the fog light on when turning the steering wheel. When I had a fault on my steering angle sensors, the active curve illumination didn't work right. That showed up on the dash as an ESP error. Other possibility is that you've got some other fault.

Izrud

Yes, I have Bi-Xenons from the P2 package. It seems that the foglight is constantly on regardless of whether the car is on park, the steering wheel straight, etc. It might be as you suggest the steering wheel sensor. However there seem to be no other signs or symptoms of malfunction. Isn't this steering wheel sensor supposed to throw a code? Or in the least, it seems weird that the only thing affected would be a fog light. Great input however, thank you. At least I have a clue as to what the issue might be.

cetialpha5

Yes, the ESP error turned out to be the steering angle sensor. I used an X431 Launch EasyDiag Plus to get the MB code. They're around $60 on eBay. Do the headlights do that little dance when they turn on? Does the right come on when you turn the steering wheel right? I think signaling also turns it on.

Izrud

I have a friend running the latest MB software through an emulator on his laptop, will stop by his house and see if I am throwing any MB codes. Thanks again for the input. It seems that worst case scenario if I have to change it shouldn't be more than $500 labor+parts.

cetialpha5

The angle sensor itself is $150, but I doubt that's the problem, probably something else associated with active curve illumination. Let us know.

cMazara

But, do you have active curve or not?

Fogs aren't supposed to come on on Auto mode, just on manual mode and when pulled..
The only way is with active curve.. I want them to be on also but I think it's not possible..

cetialpha5

P2 was Bixenons with active curve illumination and keyless go. All the Bixenons of that year have it.