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

See also:
Functional requirements
The system must have been reset when the inflation
pressure was correct; otherwise, reliable
signaling of a flat tire is not ensured. Always use
wheels with TPM electronics to ensure that the
...
Mobile communication devices in the
vehicle
Mobile communication devices in the vehicle
It is advised that you do not use mobile communication
devices, e.g., mobile phones, inside the
vehicle without connecting them directly to the
exte ...
Releasing
With the ignition switched on:
Automatic transmission: Press
the switch
while the brake is pressed or transmission
position P is engaged.
The LED and indicator lamp go out.
The parking bra ...
