I had no brakelights so my mechanic replaced the switch located below the master cylinder and then I had brake lights. He also changed the brake fluid and flushed the lines since the car already had about 93K and was due anyway. Shortly thereafter the BAS/ESP light started to come on after driving for about 10 minutes or thereabouts, depending on how much I used the brakes. Of course, when the light comes on, if you place the car in park with the motor running it won't come out again unless you re-start the engine (or overide with a pencil at the back of the shifter). I looked in the book and tried the remedy of turning the wheels lock to lock - no luck.
Do any of you have any suggestions? Any chance changing the switch or the fluid could have played a role? Should I bite the bullet and take it to the MB dealer and see what the code is?