Mercedes-Benz W204 ESP control unit (N30/4) internal fault
200 CDI220 CDI
Mercedes-Benz W204: what do fault codes 5001, 5944 and 5945 mean?
The codes indicate an internal fault in the ESP control unit (N30/4). The ESP and ABS lights often come on when the speed exceeds about 20 km/h, and they can sometimes go out on their own. The fault is read with a Mercedes-Benz diagnostic tool.
Mercedes-Benz W204: what causes an internal fault in the ESP control unit?
The cause varies. A common cause is cold solder joints in the control unit's electronics module. Sometimes moisture or the hydraulic unit is suspected. Before replacing the part, the fault should be confirmed by diagnosis.
Mercedes-Benz W204: does a used ESP unit fix the fault?
Not always, because used units often have the same fault. After replacement the system is bled. The brakes are safety-critical, so have a workshop do the replacement and check the result.
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