Anti-Lock Brake System: Operation

Under normal driving conditions, Anti-Lock Brake System (ABS) functions like a standard brake system. With detection of impending rear wheel lock-up, the ABS control module modulates hydraulic pressure to the rear brakes to prevent lock-up.

With detection of wheel lock-up, short pedal pulsations, occurring in rapid succession, will be felt in brake pedal and steering wheel. Vehicle body may also vibrate slightly. These conditions are normal. Pedal pulsation will continue until there is no longer a need for anti-lock function or until vehicle is stopped.

Diagnose ABS using a jumper wire connected between ground and short connector while observing ABS warning light on instrument cluster. When a malfunction is detected, the ABS control module will retain a diagnostic trouble code in memory. If ABS warning light remains on or flashes after engine has been started, a diagnostic trouble code is present.