TCS and ESP mode

The pump is continuously active during ESP and TSP modulation with braking.

Pressure is built up by closing the pressure relief valve and opening the pressure increase valve to supply the pump with brake fluid. The control module closes the pressure increase valve when a pre-set pressure is reached.

The pressure is then modulated as the control module opens the pressure increase valve to boost the pressure, keeps the pressure increase and pressure relief valves closed (to maintain pressure) and opens the pressure relief valve to reduce the pressure. The excess brake fluid resulting from opening the pressure relief valve is returned to the master cylinder.