See also:

Close the windows and glasssunroof
Driving with the glass sunroof and windows open results in increased air resistance and raises fuel consumption. ...

General information
The navigation system can determine the precise position of the vehicle, with the aid of satellites and vehicle sensors, and can reliably guide you to every entered destination. Navigation data ...

Deleting all stored programs
Press both outer memory buttons 1 for approx. 20 seconds until the LED flashes rapidly. All stored programs are deleted. The programs cannot be deleted individually. ...