Antilock Brakes / Traction Control Systems: Description and Operation

Anti-Lock Control - 4-Wheel
The 4-wheel anti-lock brake system (4WABS) consists of the:
^ anti-lock brake system (ABS) module.
^ hydraulic control unit (HCU) (serviced separately from the ABS module).
^ front wheel speed sensor.
^ front wheel speed sensor ring.
^ rear wheel speed sensor.
^ rear wheel speed sensor ring.