See also:

Remove attached parts following use
Remove auxiliary mirrors, roof or rear luggage racks which are no longer required following use. Attached parts on the vehicle impair the aerodynamics and increase the fuel consumption. ...

Closing the windows and glass sunroof/panoramic glass sunroof
Driving with the glass sunroof/panoramic glass sunroof and windows open results in increased air resistance and raises fuel consumption. ...

Context help - Owner's Manual to thetemporarily selected function
The relevant information can be opened directly. Opening during operation via iDrive To move directly from the application on the Control Display to the options menu: 1. Press the button or move ...