Operation of the braking system (VW Passat B4)

As soon as the wheel slows down or starts to slip, which indicates the beginning of its locking, the isolating electromagnetic valve of this brake circuit, according to the signals of the electronic control unit, interrupts the supply of brake fluid to the wheel cylinder of the wheel brake mechanism, thereby maintaining a constant brake pressure. If the wheel still locks, the delivery electromagnetic valve opens and connects the wheel cylinder to the hydraulic unit reservoir, as a result of which the brake pressure decreases and the wheel is released.

This opens the inlet solenoid valve and closes the outlet valve, resulting in normal brake pressure being established.

The described cycle is repeated several times per second until the car stops or the brake pedal is released.

The anti-lock braking system operates when the vehicle speed is at least 7 km/h.

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