DTC C1742: Wheel Cylinder Pressure Sensor

DTC detecting condition: 

• A fault is detected if the condition that supply voltage for the fluid pressure sensor is out of normal judgment range continues for predetermined time.
• A fault is detected if the communication status of fluid pressure sensor is abnormal.
• A fault is detected if the data of fluid pressure sensor is abnormal.
• A fault is detected if the offset value of fluid pressure sensor signal exceeds a predetermined judgment value.
• A fault is detected if a difference between fluid pressures for the wheels exceeds a predetermined judgment value.
• A fault is detected if master cylinder pressure and fluid pressures for the wheels exceed predetermined judgment values.

  Trouble symptom: 

  EyeSight does not operate. (Models with EyeSight)

1. CHECK STOP LIGHT SWITCH CIRCUIT AND INSTALLATION CONDITION  .

   Check the stop light switch circuit and the installation condition.

   Is the check result OK?

   Yes:  Go to  2.

   No:  Repair the stop light switch circuit or correct the installation condition.

2. CHECK OUTPUT OF PRESSURE SENSOR WITH SUBARU SELECT MONITOR  .

   Using the Subaru Select Monitor, read data of [FL wheel cylinder pressure sensor output], [FR wheel cylinder pressure sensor output] in the [Data Monitor] of [Brake Control]. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DATA MONITOR .

   With the brake pedal released, are the values of [FL wheel cylinder pressure sensor output] and [FR wheel cylinder pressure sensor output] between 0 - 11 bar?

   Yes:  Go to  3.

   No:  Replace the VDCCM and H/U. Ref. to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM AND H/U) .

3. CHECK OUTPUT OF PRESSURE SENSOR WITH SUBARU SELECT MONITOR  .

   Using the Subaru Select Monitor, read data of [FL wheel cylinder pressure sensor output], [FR wheel cylinder pressure sensor output] in the [Data Monitor] of [Brake Control]. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DATA MONITOR .

   When the brake pedal is operated, do the values of [FL wheel cylinder pressure sensor output] and [FR wheel cylinder pressure sensor output] change in accordance with the brake pedal? In addition, is the difference between [FL wheel cylinder pressure sensor output] and [FR wheel cylinder pressure sensor output] values less than 10 bar?

   Yes:  Go to  4.

   No:  Replace the VDCCM and H/U. Ref. to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM AND H/U) .

4. CHECK VDCCM AND H/U  .
   1. Using the Subaru Select Monitor, perform the clear memory of [Brake Control]. Ref. to COMMON (DIAG)>CLEAR MEMORY .
   2. Execute the inspection mode. Ref. to BRAKE CONTROL (DIAGNOSTICS)>INSPECTION MODE .
   3. Read the DTC of [Brake Control] using the Subaru Select Monitor. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is the same DTC displayed?

   Yes:  Replace the VDCCM and H/U. Ref. to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM AND H/U) .

   No:  Go to  5.

5. CHECK DETECTION OF OTHER DTCS FOR VDC  .

   Read the DTC of [Brake Control] using the Subaru Select Monitor. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is any other DTC displayed?

   Yes:  Perform the diagnosis according to the DTC. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

   No:  Currently, it is normal. There may have been a temporary poor contact in the harness and connector or a temporary noise interference.