Anti-Lock Brake Sensor
The ABS uses four variable-reluctance sensors and toothed anti-lock sensor indicators to determine the rotational speed of each wheel. The sensors operate on the magnetic induction principle. As the teeth on the indicator rotate past the stationary sensor, a signal proportional to the speed of the rotation is generated and sent to the anti-lock brake control module through a twisted pair wire cable and wiring harness.
The anti-lock brake control module monitors the electromechanical components of the system. Malfunction of the ABS will cause the anti-lock brake control module to shut off or inhibit the system. However, normal power assisted braking remains. Malfunctions are indicated by the yellow ABS warning indicator inside the vehicle.
The ABS is self-monitoring. When the ignition switch is placed in the RUN position, the anti-lock brake control module will perform a preliminary self-check on the anti-lock electrical system indicated by a two to three second illumination of the yellow ABS warning indicator in the instrument cluster. At 6.4 km/h (4 mph) , the valves and motor will be powered briefly to verify proper function. During vehicle operation, including normal and anti-lock braking, the anti-lock brake control module monitors all electrical anti-lock functions and some hydraulic operations.