Running-in the Brakes

The function for running-in the parking brakes only has to be carried out if

• the linings of the duo-servo parking brakes have been replaced or
• the rear brake discs have been replaced.

In either case, a material/surface pairing then initially exists which does not yet have the optimum frictional properties. That means that the required braking forces could not be achieved.

The brake running-in function removes play between the two surfaces forming the frictional pairing, i. e. the brake linings and the inside of the brake disc recess. It also wears-in the surfaces. Both operations are essential to achieving the required frictional coefficient between the two surfaces.

The brake running-in function is prepared with the aid of the BMW diagnosis system. It is started by pulling out the parking brake button once. The parking brake indicator lamp flashes red throughout the entire sequence.

While running-in the parking brakes, the EMF applies a defined force to the duo-servo parking brakes. That force is substantially lower than the brake force required to hold the vehicle stationary. The rear wheels are then rotated either on a brake dynamometer or by driving the vehicle on the road.