Brake Pressure Applied/Brake Deactivator Switch

Brake Pressure Applied (BPA) switch is sometimes called Brake Deactivator switch for vehicle speed control deactivation, is a normally closed switch, which supplies battery positive voltage (B+) to PCM when brake pedal is not applied. When brake pedal is applied, the normally closed switch will open and power is removed from PCM. On some applications the normally closed BPA switch along with the normally open Brake Pedal Position (BPP) switch are used for a brake rationality test within PCM. PCM misfire monitor profile learn function can be disable if a brake switch failure occurs. If one or both brake pedal inputs to PCM did not change states when they were expected to, DTC P1572 may be set by PCM.