I have a buddy who has a 2001 SLK 320 after driving the car for a while every now and again the BAS/ESP light comes on. I tried replacing the brake light switch but that didn't fix the issue. What are the other more common parts that trigger this light to come on? Thanks

There are about 30 different codes for that system.

Having the ESP computer scanned for codes would be a logical starting point since the brake lamp switch didn't do the trick.

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