Return pump
Return pump |
The pump unit, which is only activated when an outlet valve is open, returns surplus brake fluid to the master cylinder.
The pressure in the return-fluid line is determined by the brake pressure in the master cylinder, which, in turn, is proportional to the pedal pressure.
The pump's capacity of approximately 250 bar is sufficient for all occurring braking conditions.
Each time the ignition is switched on and the road speed exceeds 6 km/h, the control module checks the operation of the return pump, activating it for 200 ms. If the brake-light switch is closed, the test will be done at a speed of 15 km/h.
The hydraulic pump and electric motor are an integral part of the valve block and cannot be replaced separately.