See also:

Activating HDC
Press the button; the LED above the button lights up. ...

Functional readiness of the airbag system
When the ignition is switch on, the warning lamp in the instrument cluster lights up briefly and thereby indicates the operational readiness of the entire airbag system and the belt tensione ...

Switch off any functions thatare not currently needed
Functions such as seat heating and the rear window defroster require a lot of energy and consume additional fuel, especially in city and stopand- go traffic. Therefore, switch off these function ...