Front and Rear Brake Linings State of Wear

Condition Based Service (CBS)

Principle of Operation

Front and Rear Brake Linings State of Wear

The brake lining state of wear on the front and rear axle is confirmed and detected by 2- stage brake lining wear sensors. These are located on the left front and right rear brake pads. The first stage (reference point for the calculation) of the wear indicator is activated when the thickness of the lining is 6 mm, and the second when it is down to 4 mm.

The brake lining wear sensors voltage signals are monitored by the DSC control module. The brake lining wear sensor operates in the first stage as on current models and a resistor was added for the second stage.

The algorithm is controlled by these two different voltages in the control module and determines the residual thickness of the brake lining. The residual wear of the brake lining is calculated from the following input parameters:
- Wheel speed
- Brake disc temperature
- Brake pressure
- Braking time
- Braking frequency
- Mileage (travel distance)

The residual wear of the brake lining on the front and rear axles is stored in the DSC control module when the ignition is switched "OFF" and is used as the starting value the next time the vehicle is started.

The residual distance to the next service is forwarded by the DSC control module to the instrument cluster by a bus message when the ignition is switched "ON." The "Front or Rear brake linings" service due date is displayed in the instrument cluster or the Control Display.

Note: The instrument cluster and the DSC control module must not be replaced simultaneously, otherwise all current oil maintenance schedule data will be lost.