See also:

Switching on/off manually
Press the button. ▷ On: the LED lights up. ▷ Off: the LED goes out. If Top View is displayed, switch on the backup camera via the iDrive, ...

Office
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Safety belt reminder for the driver's and front passenger seat
The indicator lamp flashes or lights up and a signal sounds. Make sure that the safety belts are positioned correctly. The safety belt reminder is active at speeds above approx. 5 mph/8 km/h ...