Anti-Lock Brake System: Description

The Anti-Lock Brake System (ABS) keeps wheels from locking up under extreme braking conditions. ABS prevents excessive wheel slip by pulsing modulation of brake pressure. The ABS Electronic Control Unit (ECU) monitors wheel speed. If any wheel slows too quickly (approaches lock-up) during brake actuation, ECU will signal hydraulic unit to reduce pressure to that wheel to prevent lock-up.

ABS system consists of Wheel Speed (W/S) sensors, sensor rotors, ABS warning light, ABS Electronic Control Unit, ABS modulator and modulator sub-assemblies. See Figure .