No Alarm When Door Is Opened

(Step B1) Checking the door contacts




- Deactivate the alarm.




- Ignition on.




- Ignition off.
- Check that the interior light switch is in position door.




- Open a door.
The interior light should come on.




- Close the door concerned.
An armature with prolonged interior lighting should go out after about 20 seconds.
An armature without prolonged interior lighting should go out immediately.

Try all doors
- Repeat the procedure on the remaining doors. The interior light should come on when each door is opened.

If all results are correct:
There is a break in the lead from connector C1 item 30 to the alarm relay base item T.
- Check connections. Refer to Fault Alarm Wiring. Checking Leads and Connection
Rectify fault or renew the lead.

If there is a deviation
- Investigate interior wiring.

(Step B2) Checking signals from the central locking relay




- Ignition off.
- Remove the alarm control module (item C/F).




- Close all doors, the hood and the trunk




- Connect an ohmmeter between item T and item 31 on the alarm relay base.
The ohmmeter should read infinity when all doors are closed.

If the reading is correct:
- Proceed to ohm test below.

If the reading deviates:
- Continue with step B3.




- Open a door.




Ohm Test
- Connect an ohmmeter between item T and item 31 on the alarm relay base.
The ohmmeter should show approx. 0 ohms when the relevant door is open.

If the reading is correct:
There is most likely a fault on the control module.
- Carry out fault tracing. Fault Tracing Alarm Wiring

If the reading deviates:
- Continue with step B3.

(Step B3) Checking the signal lead from the central locking relay




- Ignition off.
- Disconnect central locking relay items (D/G).




- Connect an ohmmeter between the alarm relay base item T and the central locking relay base item T.
The ohmmeter should show approx. 0 ohms.

If the reading is correct
There is most likely a fault on the alarm control module.
- Proceed with fault tracing. Fault Tracing Alarm Wiring

If the reading deviates:
There is a break in the lead between the alarm relay base item T and the central locking relay base item T.
- Rectify the fault or change the lead.
Replace the central locking relay.
Replace the alarm control module.