Parking Brake System: Description and Operation

The parking brake system is applied by depressing the parking brake pedal. Applying the parking brake pedal places tension on the parking brake cables, which actuates the rear parking brake mechanism. This system mechanically forces the rear brake shoes against the brake drums which locks the rear brakes.

This section covers parking brake component replacement and adjustment. The parking brake must be adjusted any time the parking brake cables have been replaced or disconnected, or if the parking brake holding ability is inadequate.

The parking brake is not designed for use in the place of service brakes and should be applied only after the vehicle is brought to a complete stop, except in an emergency.

Before working on the parking brake system, make sure the service brakes are in good working order and adjusted properly.

Circuit Description

Battery voltage is supplied to the Brake Indicator through the GAUGES Fuse and the PNK (39) wire when the Ignition Switch is in RUN or START. Ground is provided through the TAN/WHT (33) and LT BLU (1134) wire by the Park Brake Warning Switch, Brake Pressure Warning Switch or the TAN/WHT (33) and PPL (680) and the Brake Pressure Modulator Valve (BPMV).

The Park Brake Warning Switch closes when the Parking Brake is applied. The Brake Indicator lights to alert the driver.

The Brake Pressure Warning Switch closes to light the BRAKE Indicator when there is low brake fluid pressure in one of the two hydraulic brake systems. This could be caused by a leak in one of the brake lines.

The 2.2 L Engine's Electronic Brake Control Module (Part of the Brake Pressure Modulator Valve) or the 4.3 L Engines Vehicle Control Module grounds the BRAKE Indicator when the module senses certain malfunctions in the hydraulic portion of the system. The module grounds the ANTILOCK Indicator when the module senses a malfunction in the electrical or electronic portion of the system. Brake voltage input is supplied to the module through the TCC Brake and Cruise Control Release Switch whenever the brakes are applied.