C20 Checking Locking Signal Cables

- Switch off ignition.
- Reconnect the central locking module's 6-pin connector in the front door.




- Lock all doors and tailgate/trunk.




- Connect an ohmmeter between pos. 31 and pos. 86 on the relay base terminal.
The ohmmeter should show approx 0 Ohms.




- Unlock all doors and tailgate/trunk.
- Connect an ohmmeter between pos. 31 and pos. 86 on the relay base terminal.
Ohmmeter should indicate infinite resistance.




If both values OK:
Open circuit or short circuit in unlocking signal cable between driver's door and central locking relay.
- Correct fault or install new signal cable driver's side between relay base terminal pos. 85A and the cable harness 6-pin connector pos. 3.
Replace central locking relay D/G.

If reading is incorrect:
Open circuit or short circuit in locking signal cable between driver's door and central locking relay.
- Correct fault or install new signal cable driver's side between relay base terminal pos. 86 and the cable harness 6-pin connector pos. 2.
Replace central locking relay D/G.