General Description

PURPOSE
The purpose of the Antilock Brake System is to prevent wheel lock-up under heavy braking conditions on virtually any type of road surface. Antilock braking is desirable because a vehicle which is stopped without locking the wheels will normally stop in a shorter distance than a car with locked wheels, while retaining directional stability and some steering capability. This allows the driver to retain greater control of the vehicle during heavy braking. This system utilizes a diagonally split master cylinder, booster, ABS hydraulic modulator and rear mounted proportioner valves.

OPERATION
The hydraulic modulator is controlled by an Electronic Brake Control Module (EBCM) which is a small computer mounted in the trunk on the left wheelhouse. The EBCM receives wheel speed information from four wheel speed sensors, one at each wheel, and controls the hydraulic modulator to prevent wheel lock-up under virtually all braking conditions. Further information regarding operation of the Antilock Brake System may be found in Antilock Brake System AND Traction Control System. A front and rear disc brake system is used on all models. The disc brakes are of the single piston floating caliper design. The front rotors are fully ventilated with cooling fins cast integrally between machined braking surfaces. When the wheel is in motion, the rotation of the rotor fins increases air circulation for more efficient cooling. The rear rotors are a single unventilated cast disc. The front linings are forced against the rotor by hydraulic pressure from activating the service brake pedal. The rear linings are forced against the rotor by either hydraulic pressure from activating the service brake pedal or by mechanical pressure from applying the parking brake.