Antilock Brakes / Traction Control Systems: Description and Operation

ABS OPERATION
If the brake pedal is depressed suddenly, the ABS controls the hydraulic pressure of the wheel cylinders to automatically avoid wheel locking and ensure the directional and steering stability of the vehicle.

In sudden braking, the ABS ECU controls the solenoids in the actuators using the signals form the sensors to move the brake fluid to the reservoir in order to release the braking pressure applied to the wheel cylinder. If the ABS ECU detects that the fluid pressure in the wheel cylinder is insufficient, the ABS ECU controls the solenoids in the actuators to increase the braking pressure.

FAIL-SAFE FUNCTION
If an error occurs in the ABS ECU, sensor signals and/or actuators, the ABS ECU inhibits the brake actuator control. According to this, the brake actuator turns OFF the solenoid and the vehicle operates without the ABS system.