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Brakes applied with ABS modulation

Brakes applied with ABS modulation


ABS modulation is activated when the system detects a tendency for a wheel to lock. The ECU receives information on the wheel velocity. If the wheels show a tendency to lock the control unit modulates the braking force with the aid of solenoid control valves. The braking force is regulated separately on each wheel.

It is only in the ABS position with the outlet valve open that the return pump is activated and returns excess brake fluid to the master cylinder.

The pressure of the brake fluid supplied is determined by the brake pressure in the master cylinder, which is proportional to the force applied to the brake pedal. The pressure in the respective circuits is dependent on the retardation in wheel speed sensed by the sensors. The electronic control module controls the intake and outlet valves so that a maximum braking force (coefficient of adhesion) is maintained between the wheel and road surface.

ABS modulated braking will continue until:


• The vehicle halts.

• The driver decreases the force applied to the pedal so that the relationship between braking force and road surface allows braking force to resume without danger of the wheels locking.