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

See also:
Display
1 Lane departure warning
2 Active Cruise Control
3 Desired speed
4 Navigation system
5 Speed
The collision warning, Night Vision pedestrian
warning, or Check Control messages are displayed
...
Pedestrian detection
The pedestrian detection and warning system
only operates in darkness and only when a heat
image is displayed.
Warm objects that are similar in shape to human
beings are detected by the syste ...
Switching on/off manually
Press the button.
On: the LED lights up.
Off: the LED goes out.
The PDC is shown on the Control Display.
Switch on the backup camera via the iDrive. ...
