Brake Pressure Switch
The brake pressure switch is integrated with the brake pedal position (BPP) switch. When the brake pedal is applied, the normally closed brake pressure switch opens the circuit.
The normally closed brake pressure switch, along with the normally open BPP switch, is used by the PCM strategy for a brake pedal rationality test. The PCM strategy looks for each switch to change states when the brake pedal is applied and released. If a failure occurs in one or both of the brake pedal inputs a diagnostic trouble code is set and the PCM misfire on board diagnostic (OBD) monitor is disabled.