See also:

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 ...

General information
Switch position: 0, If the driver door is opened with the ignition switched off, the exterior lighting is automatically switched off at these switch settings: ...

Switching on automatically
Select transmission position R with the engine running. The backup camera image is displayed if the system was switched on via the iDrive. ...