Door Lock Heating

If installed, door lock heating is switched on by raising the driver's door handle. The vehicle must be locked and the handle raised for at least 5 seconds. The central locking module controls the door lock heater through a separate relay, applying power for a maximum of approximately 35 seconds, or until the door is unlocked. A repeating arrest of 16 minutes is activated if door lock heating is activated three times within 16 minutes. The repeating arrest can only be discontinued before the 16 minutes has elapsed by unlocking the door.


More detailed information is available in the E36 Electrical Troubleshooting Manual in the following sections:

Schematics: 5120.1
Diagnostic Procedures: 5120.2A