Brake Fluid Pump: Description and Operation

Fig. 4 Electric Pump Assembly:

This system uses high pressure brake fluid stored in a hydraulic accumulator, Fig. 4, for power assist as well as for rear wheel braking. The accumulator is a gas filled pressure chamber that stores brake fluid up to 2600 psi. The fluid is pressurized by an electric motor driven pump. The pump is switched on and off automatically by a pressure sensing switch through a relay circuit.