Mercedes M Klasse Hybrid ABS Fault

The ABS system uses speed sensor input from each wheel These sensors send data to the control unit, which modulates braking force to prevent wheel lockup A faulty sensor or the control unit could cause these symptoms If the speedometer is acting up, that suggests a problem with the speed signal Have you checked the wiring and connections to the ABS sensors for damage or corrosion

When you mention wiring and connections, are you referring to the physical wiring harness leading to each wheel speed sensor, or are there other connections I should inspect I can use a multimeter, so if there are specific voltage or resistance values I should be looking for, please let me know

Yes, I meant the wiring harness at each wheel speed sensor, and the connections where the harness plugs into the sensor itself While voltage and resistance values can be helpful, they vary a lot depending on the sensor type and vehicle model Given the complexity of the ABS system, it might be best to consult a qualified technician A defective ABS control unit often needs specialized diagnostic equipment and programming to replace This could save you time and money

I appreciate your candor It seems there could be further complications I'll take your advice and schedule an appointment with a Mercedes-Benz technician After consulting with the technician, the control unit was faulty and needed replacement The cost was around 1000€ Thanks again for your help