Normal Operation
WARNING: This page is about a different car, the 2009 Ford RV Cutaway, 2009 Ford Econoline, 2009 Ford E450 Super Duty, and 2009 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
The brake fluid pressure transducer supplies a voltage signal to the PCM that varies with the force applied to the brake pedal, more force equals more voltage. The PCM supplies 5 volts to the transducer, this voltage travels through the transducer and then back to the PCM along 2 other circuits, a signal input circuit and a voltage return (or ground) circuit.
- DTC P1561 (Brake Line Pressure Sensor Circuit) - If a short to voltage or an open condition exists on any of the 3 circuits or if the transducer is indicating high pressure for more than 5 seconds while the Brake Pedal Position (BPP) switch (also known as the stoplamp switch) is indicating no brake application, DTC P1561 will be set.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- BPP switch
- Brake fluid pressure transducer
- PCM