The heating process can only take place when the engine is running and is triggered by pressing the "Rear window defroster" button. Automatic shutoff takes place after approx. 15 minutes. If the heating process is interrupted prematurely, the button must be operated again.
The heating process is terminated if the engine is switched off and must be restarted by pressing the button once the engine is started again.
The indicator lamp in the button lights up when the rear window defroster is switched on.