Brake Fluid Pump: Description and Operation

An integral pump/motor assembly is used to provide pressurized brake fluid to the hydraulic unit accumulator. The pump/motor assembly is mounted on the left side of the hydraulic unit, with pressure and return hoses running to the booster inlet and reservoir. Pump operation is controlled using the pump motor relay, located on the underhood relay bracket near the center of the vehicle. The pump motor relay coil is powered whenever the ignition switch is in the RUN position.