I have an ML430 1999 (W163):
Just recently, the ETS & EPS & Brake indicator lights came on accompanied by loud beeping (as if my door was ajar with the keys in the ignition).
This doesn't happen all the time; but when it does happen, it's only when I'm driving forward or reverse. When I'm stopped at a light, the beeping stops, but then resumes once I accelerate. Sometimes I can get the lights and beeping to turn off by shutting down my engine . . . sometimes not.
Somedays I can drive all day without any indicator lights coming on or the anoying beeping noise that goes with them.
I've already had my brake switch change . . . not the solution.
Any clues would be greatly appreciated . . . Thanks.