I just had this message pop up in the display when I started the car. Lane keep assist inoperable. Shut it off started again and had the same message. It's cold outside like 10 degrees not sure if that has anything to do with it. Also car is salty from winter driving. Anyone had this problem or know where the sensors for this system are?

 

I believe there is a camera in the rear view mirror area of the windshield. Try cleaning the windshield and see if that helps.

 

I had similar problem with my radar sensors that disabled the blind spot assist which required to replace both sensors in my E550. They were busted wide open, and it was a costly affair.

 

Well good thing I have a warranty. I started it this morning going to work and no problems works fine. Maybe just a fluke I'm hoping