Pump Motor Circuits: Notes

Operation of the pump/motor assembly is controlled by the pressure monitoring module in the sensor block, through the pump motor relay. The pressure monitoring module includes a pressure switch with two redundant sensors which read accumulator pressure. Output from these two switches is compared to determine if the pressure switch assembly is operating properly. If the readings do not match, anti-lock function is disabled and the BRAKE warning lamp is illuminated.

The pressure monitoring module is calibrated to turn the pump motor on at an accumulator pressure of approximately 2100 psi (14,500 kPa) and to turn the pump motor off at approximately 2600 psi (18,000 kPa).