Fault Code 1504

Fault code 1504

Number plate light

NOTE: This fault was detected by the 'rear convenience system' control module.

Diagnostic conditions
- Ignition on
- Battery voltage OK (11.4 to 14.5 V)
- Internal rear convenience system control module function test
- Parking light on

Possible causes of fault
- Short circuit to ground
- Open circuit
- Both number plate light bulbs faulty

Affected pins
Rear convenience system control module, plug A:
- Pin 9 'number plate lights'

Diagnosis/troubleshooting

NOTE:
Visual inspection: In the next troubleshooting section, please check first that the affected pins on the rear convenience system control unit 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: In the rear area of the wiring harness there is a 10-pin plug connection and, for the basic outfit, in the rear lid area (left) a further 10-pin plug connection that must be included in the checks. For vehicles with M-outfit external spare wheel, this 10-pin plug connection (rear lid, left) is replaced by a 10-pin plug connection in the bumper area.