I bought a brake light switch to fix a ABS BAS ESP error. I took the panel off to gain access to the brake switch then removed another panel and saw where the switch yet there was not one in there or any wires nearby. This tell me I looking in the wrong spot. There is a bracket and notches that allow it to be installed there but not wires. Another hint is that the 2nd cover took off over the pedal would not be able to be reinstall if I put a switch there it would hit it . That tells me it has to be somewhere else for this model 4 matic. Where else should I look ?

Karajy,
Starting model year 2002 1aug01 the brake light signal is generated in the ESP/BAS module. You have no physical switch at the pedal.

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Paul

I don’t know how similar your ‘05 is to earlier 203s but there’s some info in this thread from post #499.

https://mbworld.org/forums/c-class-w203/331654-all-about-trey-cars-20.html

Sixto
98 E320s sedan and wagon
02 C320 wagon

WOW that helps allot I wasted my money buying a switch. No wonder the bracket was there but no switch

So can some one help me with my other problem chasing this error on a car I bought for my daughter and 10 miles into owning it we can not drive it.
The ABS ESP BAS came on while in a drive though getting food. Also was lock in park but I figure out that trick to get me home . We are now in limp mode
I had a mechanic run a scan and said it was the module. I sent it out to get fixed they send it back, I installed it and no change after driving it 1 mile it set off no speedo and limp mode. I reset the module by disconnecting it then re-connecting drive a mile same result. I then replaced the right rear ABS speed sensor , and that did not help NOW WHAT ?????? How do you pin point this problem . I see many post but different fixes for all the same scenarios.... it always fails after 1 mile of a reset.