Hello together, first of all only ABS/ESP on my SLK170 230K FL Bj 2002 lit up. I went on with it, because I wanted to look for the speed sensors at the summer tire change. After a few days the motor lamp came in and the automatic switched no more. Diagnosis of MB ESP control unit defective, all possible known error messages appeared. After replacement by a free workshop with an replacement part the errors are still present, in addition now the manual brake lamp and the brake lining display. Error codes are all possible as described by other threaders as well. Since I do not believe that the AT control unit is also defective, what MB claims again is the question of what it could still be. To exchange all possible sensors makes no sense, as long as no communication with the control unit is possible. What have I done so far: fuses checked, K40 removed and checked, all soldering points see s Aber auber off, power supply measured on the ESP connector (upper pins) 12.4V without ignition, 11.7 volts with ignition. Is the power supply too low? can I check otherwise why no CANBus communication with the control unit is possible? I am grateful for all ideas and suggestions. Additional info: Tacho is not working again and again. If I delete all errors (one I cannot delete myself) is at least the engine light off and you can drive in the second gear. rt then again motor light on and only first gear. Greetings Dieter