Has any one replace a brake light switch on a 2001 c320 meb.(where is it ect)
any help thanks

 

You will need a T25 (Torx) or Phillips screwdriver. The switch is located under the drivers dash at the brake pedal. Remove the panel (4-5 screws) be careful of the small footwell light, and follow the pedal up to the firewall (youu will see many, many, many wires but don't be scared). The switch has 2 plug connections and a tab. Hold the tab and rotate the switch 90 degrees L or R and pull straight out. To install (this is the fun part) You have to hold the pedal all the way to the floor and install as you removed. Tab in same position as removed and rotate into place. You should hear a slight click (Tab seating). Then pull the brake pedal up as far as it will go and plug in the connectors. It is vital for proper function that you pull out the white or black piece on the end of the switch all the way out before installing (it will click as you pull it out). This is the trigger for the switch. Your lights go on as the end of the switch reaches its end point. Also your supposed bad switch is adjustable. Before replacing remove your old switch, pull out the end, and reinstall. That may be all you needed in the first place.

 

Silverstartech, thank you for the thorough post. THe removal was easy. Out of curiousity, I then tested the switch with an Ohm meter. I was surprised that one pair of pins is Normally CLosed, and the other is Normally Open. They then change state upon depressing the brake pedal. Meaning, it appears to me, when the brake pedal is not pressed, there is one pair of pins with connection made, and the other pair is open. Pressing the pedal swaps states.
THe table below perhaps makes it clearer:

Pedal position____ pin pair 1_____ pin pair 2
------------ _____ --------_____---------
at rest __________open_________closed
depressed _______closed _______open

QUESTION 1: IS this the expected behaviour:?

QUESTION 2: If so, why do my brake lights continue to NOT light up?

If I reconnect the switch and actuate it by hand, as if the brake pedal is doing it, I see no brake lights, in any location. My 2002 C320 manual states that the brake lights are NOT fused (this is the only circuit that isn't, for some reason). So I assumed the problem must lie with the switch, but it seems to be fine... or not?