Brake Fluid Pressure Sensor/Switch: Description and Operation

Brake Pressure Switch Description and Operation

The BPS serves two purposes; first, it is an input to the ABS control module to indicate that pressure exists in the Brake Master Cylinder, second, it is a back up input to the PCM for cruise control, it indicates the brake pedal has been pressed in addition to the Brake On Off (BOO) switch. (For cruise control the Brake Pressure Switch is sometimes referred to as the Deactivator Switch).

The BPS is a normally closed switch. It provides a B+ signal to the ABS control module, this switch opens circuit momentarily when the brake pedal is pressed hard.