Parking Brake System: Description and Operation

Park Brake System Description and Operation

Note:
Plastic coated park brake cables do not need periodic lubrication.

Coated park brake cables are used to reduce apply effort and increase corrosion protection. The cables are coated with a plastic material which slides against nylon seals inside the conduit end fittings.

Mechanical Park Brake System

The park brake lever has an indicator switch which closes when the park brake is set, thus illuminating the red BRAKE lamp.

Park brake application is completely independent of the hydraulic brake system. The park brake system is a mechanical system which operates the rear disc brakes through the calipers. The system is activated by pulling the park brake lever upwards, which applies the rear disc brakes via cables. A mechanical stop in the lever will hold the lever in the chosen position. When the park brake is set and the ignition switch is on, the Park Brake warning lamp on the instrument panel will be on. The park brake is released by pushing the knob on the underside of the lever, raise it a few millimeters and then push it downwards to its lowest position. When the lever reaches its lowest position the Park Brake lamp in the instrument cluster will go out.

Electronic Park Brake System

In the electronic park brake (EPB) system the brake cables are pulled by the motor in the electric park brake control module (EPBCM). Refer to Electronic Parking Brake Control Module Description Description and Operation.

Instead of a park brake lever there is an electric switch in the mid-console. By pulling the switch upwards the park brake is activated and the park brake warning lamp in the IPC is illuminated. By pushing it downwards the park brake is released and the warning lamp goes out.

The motor in the EPCM pulls the cable to the right-hand rear wheel caliper. An equalizer is mounted on the cable and pulls the cable to the left-hand rear wheel.

The function is divided into:

* Static apply/release

* Dynamic apply/release

* Automatic release