Fault Code 0123

Fault code 0123

Rear right door warning and exit lights

NOTE: This fault was detected by the 'rear right door' control module.

Diagnostic conditions
- Ignition on
- Battery voltage OK (11.4 to 14.5 V)
- Internal function test on rear right door control module
- Open/close door

Possible causes of fault
- Wiring faulty
- Lights faulty

Affected pins
Rear right door control module, plug B:
- Pin 1 'warning light'
- Pin 8 'terminal 31, lighting'
- Pin 9 'door exit light'

Diagnosis/troubleshooting

NOTE:
Visual inspection: In the next troubleshooting section, please check first that the affected pins on the rear right door control module plug connection are neither damaged nor corroded. The wiring and plugs of the affected components must also be checked for external damage and correct contacts. Repair damaged or corroded pins if possible, otherwise replace affected pins. Repair or replace damaged wires.

NOTE:
Sporadic faults: In the event of faults that occur sporadically, the wiring positions that are linked to moving parts on and in the vehicle must be checked for each system. Various statuses that can cause faults must be simulated with the help of the wiring diagram.

NOTE:
Battery voltage: A battery voltage of between 11.4 and 14.5 V is required for the following troubleshooting procedure. This must be checked and provided, if necessary. On the vehicle electrical system, the voltage to the fuse (input side) must be guaranteed.

NOTE: The door warning light and the door exit light are activated together on opening and closing the door. The voltage supply, however, is split on two separate pins.