Pinpoint Test B: DTC P1703 Or DTC P1572

WARNING: This page is about a different car, the 2010 Mercury Mariner and 2010 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

B1 CHECK FOR ABS DTCs
- Review the recorded DTCs from the ABS self-test.
- Are any DTCs recorded?
- Yes: REFER to VEHICLE DYNAMIC SYSTEMS . REPAIR all ABS module DTCs and RETEST the system.
- No: GO to B2 .
B2 CHECK THE OPERATION OF THE STOPLAMPS
- Ignition ON.
- Operate the stoplamps.
- Do the stoplamps operate correctly?
- Yes: GO to B3 .
- No: REFER to STOPLAMPS to continue diagnosis of the stoplamps.

B3 CHECK THE STOPLAMP SWITCH (BOO1 AND BOO2) PIDs

Enter the following diagnostic mode on the scan tool: PCM DataLogger.

Monitor the PCM PIDs BOO1 (brake pedal top travel) and BOO2 (brake pedal bottom travel) while applying and releasing the brake pedal as follows:

BRAKE PEDAL POSITION REFERENCE CHART

Brake Pedal Position	BOO1 PID	BOO2 PID
Released	Off	Off
Applied lightly	On	Off
Applied firmly	On	On

Do the PID values agree with the brake pedal position?

Yes: GO to B8.
No: For an incorrect BOO1 PID value, GO to B4 .
For an incorrect BOO2 PID value, GO to B5.

B4 CHECK THE STOPLAMP SWITCH CIRCUIT FOR VOLTAGE
- Ignition OFF.
- Disconnect: PCM C175b.
- Ignition ON.
- While applying the brake pedal, measure the voltage between the PCM C175b-13, circuit CCB08 (VT/WH), harness side and ground.
  
  Fig 1: Checking Circuit
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts with the brake pedal applied?
- Yes: GO to B8.
- No: REPAIR the circuit. CLEAR the DTCs. TEST the system for normal operation.
B5 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Stoplamp Switch C278.
- Ignition ON.
- Measure the voltage between the stoplamp switch C278-2, circuit CBK02 (GN), harness side and ground.
  
  Fig 2: Checking Circuit
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes: GO to B6 .
- No: REPAIR the circuit. CLEAR the DTCs. TEST the system for normal operation.
B6 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: PCM C175b.
- Ignition ON.
- Measure the voltage between the stoplamp switch C278-3, circuit CES09 (VT/OG), harness side and ground.
  
  Fig 3: Checking Circuit
  Courtesy of FORD MOTOR CO.
- Is any voltage present?
- Yes: REPAIR the circuit. CLEAR the DTCs. TEST the system for normal operation.
- No: GO to B7 .
B7 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH CIRCUIT FOR AN OPEN
- Ignition OFF.
- Measure the resistance between the PCM C175b-46, circuit CES09 (VT/OG), harness side and the stoplamp switch C278-3, circuit CES09 (VT/OG), harness side.
  
  Fig 4: Checking Circuit
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes: INSTALL a new stoplamp switch. REFER to STOPLAMP SWITCH . TEST the system for normal operation.
- No: REPAIR the circuit. CLEAR the DTCs. TEST the system for normal operation.
B8 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the PCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes: INSTALL a new PCM. REFER to POWERTRAIN CONTROL MODULE (PCM) 2.5L, POWERTRAIN CONTROL MODULE (PCM) 3.0L (4V) or POWERTRAIN CONTROL MODULE (PCM) Hybrid. TEST the system for normal operation.
- No: The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.