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

See also:
Automatic deactivation during forward travel
The system switches off when a certain driving
distance or speed is exceeded.
Switch the system back on if necessary. ...
Requirements
▷ The installed BMW Assist system is logged
in to a wireless communications network.
This network must be capable of transmitting
the services.
▷ To transmit position data, the vehic ...
Traction
The traction grades, from highest to lowest, are
AA, A, B, and C.
Those grades represent the tire’s ability to stop
on wet pavement as measured under controlled
conditions on specified governme ...
