ABS BY4 system from VIN 144845

ABS BY4 system from VIN 144845

The Anti – lock Brake System (ABS) modulates the pressure of the brake fluid applied individually to each front caliper and to both rear calipers, thereby preventing the wheels locking, even under hard braking. It then restores normal hydraulic pressure when there is no longer a possibility of a wheel locking.

Gear pulser and wheel sensor

The slotted gear pulser is attached to the rotating part of the wheel hub. The wheel sensor detects the slots and generates pulse signals corresponding to the revolutions of the gear pulser.

ABS control unit

Controls the working of the anti – lock brake system by performing calculations based on the signals from the individual wheel signals and the individual switches.

Modulator unit

Adjust the hydraulic pressure applied to each caliper on the basis of the signals received from each ABS control unit.

Motor relay

Controls the ABS pump motor’s power supply according to the signal from the ABS control unit.

Fail – safe relay

Cuts off the solenoid valve ground circuit when the fail – safe device is at work.

Features

• Kickback is felt on the brake pedal when the anti – lock brake system is operating.
• The system is equipped with a self – diagnosis function (DTC). When an abnormality is detected, the ABS indicator light comes on. The system’s fault can be diagnosed from the frequency of the system indicator light blinks.
• This system has individual control of the front wheels and common control ("Select low") for the rear wheels. "Select Low" means that the rear wheel that would lock first (the one with lowest resistance to lock – up) determines anti – lock brake system activation for both rear wheels.
• The system has a fail – safe function that allows normal braking if there is a problem with the anti – lock brake system.

Modulator unit
[symbol]

70M0392

The modulators unit, adjusts the hydraulic pressure to each caliper on the basis of the signals received from the ABS control unit, and consists of the following sub – units.

• ABS pump and motor: Supplies high – pressure brake fluid to the ABS operation.
• Accumulator: Stores high – pressure brake fluid.
• Pressure switch: Detects the pressure in the accumulator and transmits signals to the ABS control unit.
• Solenoid valves: Switches the ABS high – pressure passage according to the signals from the ABS control unit.
• Pistons and related parts: Receives the high – pressure brake fluid and controls pressure to the calipers accordingly.