Pinpoint Test J: DTC C1288 And C1440 - Pressure Transducer Main/Primary Input Circuit Failure And Signal Faulted

WARNING: This page is about a different car, the 2009 Mercury Sable, 2009 Ford Taurus X, and 2009 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multi-meter probes.

J1 MONITOR THE ABS MODULE BRAKE ON/OFF (BOO_ABS) PID
- Connect the diagnostic tool.
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: DataLogger ABS
- Press and release the brake pedal while monitoring the BOO_ABS PID.
- Does the PID switch to ON with the brake pedal pressed and then to OFF with the brake pedal released?
1. YES : Go to J3.
2. NO : Go to J2.
J2 MONITOR THE PCM BRAKE ON/OFF (BOO) PID
- Enter the following diagnostic mode on the diagnostic tool: DataLogger PCM
- Press and release the brake pedal while monitoring the BOO PID.
- Does the PID switch to ON with the brake pedal pressed and then to OFF with the brake pedal released?
1. YES : REFER to MODULE COMMUNICATIONS NETWORK article to continue diagnosis of the controller area network (CAN).
2. NO : REFER to EXTERIOR LIGHTING article to continue diagnosis of the BOO switch and stoplamps.
J3 MONITOR THE ABS MODULE BRAKE PRESSURE (BRAKPRESS) PID
- Enter the following diagnostic mode on the diagnostic tool: DataLogger ABS
- Firmly press and release the brake pedal while monitoring the BRAKPRES PID.
- Does the PID increase with firm pressure on the brake pedal and then decrease with the brake pedal released?
1. YES : ROAD TEST the vehicle and have an assistant MONITOR the BRAKPRES PID. If the PID increases and decreases with pedal application and release, RETURN the vehicle to the customer.
  If the PID does not increase and decrease with pedal application and release, INSTALL a new HCU. REFER to Hydraulic Control Unit (HCU) . CALIBRATE the ABS module. FOLLOW the scan tool directions for the calibration procedure. MONITOR the BRAKPRES PID while firmly applying and releasing the brake pedal.
  
  If the PID increases and decreases with pedal application and release, the system is operating correctly at this time.
  
  If the PID does not increase and decrease with pedal application and release, INSTALL a new ABS module, REFER to Anti-Lock Brake System (ABS) Module . CLEAR the DTCs. REPEAT the self-test with the brake pedal not applied.
2. NO : INSTALL a new HCU. REFER to Hydraulic Control Unit (HCU) . CALIBRATE the ABS module. FOLLOW the scan tool directions for the calibration procedure. MONITOR the BRAKPRES PID while firmly applying and releasing the brake pedal.
  If the PID increases and decreases with pedal application and release, RETURN the vehicle to the customer.
  
  If the PID does not increase and decrease with pedal application and release, INSTALL a new ABS module, REFER to Anti-Lock Brake System (ABS) Module . CLEAR the DTCs. REPEAT the self-test with the brake pedal not applied.