Normal Operation
WARNING: This page is about a different car, the 2009 Mercury Milan, 2009 Lincoln MKZ, and 2009 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
When the brake pedal is applied, voltage is sent to the PCM from the stoplamp switch through circuit CCB08 (VT/WH).
The speed control deactivator switch (part of the stoplamp switch) interrupts circuit CES09 (VT/OG) removing the voltage signal to the PCM when the brake pedal is applied firmly and passes the speed control deactivator switch point. This is a redundant signal to the PCM.
- DTC P1572 (Brake Pedal Switch Circuit) - sets when the PCM does not sense the proper sequence of the brake pedal input signal from both the speed control deactivator and stoplamp switches when the brake pedal is pressed and released.
- DTC P1703 (Brake Switch Out Of Self Test Range) - sets when there is an open or short in the deactivator switch circuits or when there is an open or short in the stoplamp circuits.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Speed control deactivator switch (integral to the stoplamp switch)
- ABS module
- PCM