Test B: DTC P1572 Or DTC P1703 Brake On/Off Circuit Failure

PINPOINT TEST B: DTC P1572 OR DTC P1703 - BRAKE ON/OFF CIRCUIT FAILURE

B1-B2:

B2-B4:

B4-B6:

B7-B9:

Normal Operation
When the brake pedal is applied, the smart junction box (SJB) sends a message to the powertrain control module (PCM) to deactivate the speed control if engaged.

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. This is a redundant signal to the PCM.

DTC P1572 - 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 - 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.

Possible Causes
- Fuse
- Circuit CBP44 (VT) open (early build Fusion, Milan)
- Circuit CBP49 (VT/GY) open (late build Fusion, Milan and MKZ)
- Circuit CCB08 (VT/WH) open
- Circuit CES09 (VT/OG) open or short to voltage
- Speed control deactivator switch (integral to the stoplamp switch)
- Anti-lock brake system (ABS) module
- PCM