The concept
The parking brake is primarily intended to prevent the vehicle from rolling while parked; it brakes the rear wheels.

See also:
Driving tips
This chapter provides you with information useful
in dealing with specific driving and operating
modes. ...
Activating HDC
Activating HDC
Press the button; the LED above the button
lights up.
The LED flashes when the brakes are applied
automatically. ...
Switching on/off manually
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. ...
