Features
When the brake pedal is pressed during driving, the wheels can lock before the vehicle comes to a stop. In such an event, the maneuverability of the vehicle is reduced if the front wheels are locked, and the stability of the vehicle is reduced if the rear wheels are locked, creating an extremely unstable condition. The ABS precisely controls the slip rate of the wheels to ensure maximum grip force from the tyres, and it thereby ensures the maneuverability and stability of the vehicle.
The ABS calculates the slip rate of the wheels based on the vehicle speed and the wheel speed, then it controls the brake fluid pressure to reach the target slip rate.
Grip Force of Tyre and Road Surface

COMPONENTS | MAIN FUNCTION
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Wheel sensor | The wheel sensor outputs the speed signal to the ABS control unit according to the encoder's (pulser's) rotation speed.
ABS modulator-control unit | ABS control unit | The ABS control unit processes the signal from the wheel sensor, then outputs the ABS control signal to the modulator unit.
Modulator unit | The modulator unit receives the control signal, then controls brake fluid pressure for each wheel.
Motor relay (inside of the ABS control unit) | The motor relay drives the ABS pump motor.
ABS fail-safe relay (inside of the ABS control unit) | The ABS fail-safe relay cuts the power to the solenoid valve when a problem is detected.