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Home >> Subaru >> 2019 >> BRZ Premium >> Repair and Diagnosis >> Brakes >> Traction Control >> Vehicle Stability Control (VSC) System >> Vehicle Stability Control System >> DTC C1246: Pressure Sensor System >> Inspection steps
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Inspection steps

CAUTION:
  • When the skid control computer (brake actuator ASSY) has been replaced, make sure to perform [VSC(VDC) Centering Mode]. (Refer to WORK SUPPORT )
  • Before performing troubleshooting, check the fuse for this circuit.
  1. Stop light illumination check
    1. Turn IG ON and depress the brake pedal to check that the stop light illuminates.

      Criteria: The stop light illuminates.

      OK: Go to next step

      NG: Stop light circuit check (Refer to SYMPTOM TABLE )

  2. Data monitor check (master cylinder pressure)
    1. Using SSM4, check [Data monitor] of [Master cylinder pressure]. (Refer to DATA MONITOR )
      RANGE DESCRIPTION

      Item name Description/display range Normal value Remarks
      [Master cylinder pressure] Indicates the output value on the master pressure sensor. Display range: -1 to 23.99MPa While the brake pedal is being operated: Varies in proportion to the depressing force.
      When the brake pedal is not operated: -1 to 0.5 MPa      		 -

      Criteria: Output value varies in proportion to the brake pedal depressing force.

      OK: Go to next step

      NG: Replacement of skid control computer (brake actuator ASSY) (Refer to REMOVAL )

  3. Data monitor check (stop light switch)
    1. Using SSM4, check [Data monitor] of [Stop Lamp Switch]. (Refer to DATA MONITOR )
      RANGE DESCRIPTION

      Item name Description/display range Normal value Remarks
      [Stop Lamp Switch] Indicates the stop light switch operation.
      Display range: OFF/ON      		 OFF: Brake pedal, released ON: Brake pedal, depressed -

      Criteria: According to the brake pedal operation, the display switches ON/OFF.

      OK: Go to next step

      NG: Go to Step  5.

  4. Diagnostic code list recheck
    1. Using SSM4, clear the diagnostic code. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES )
    2. Perform a driving test.
    3. Using SSM4 again, check the diagnostic code output. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES )
      RESULT DESCRIPTION

      Result Go to
      Normal A
      Error code B
      1. Go to next step
      2. Replacement of skid control computer (brake actuator ASSY) (Refer to REMOVAL )

      Malfunction reproduction test (Refer to MALFUNCTION SYMPTOMS AND DTC CHECK )

  5. Check wiring harness and connector (noise filter - battery)
    1. Disconnect the connector, A13 of the noise filter.
    2. Measure the voltage between the terminals.
      STANDARD VALUE SPECIFICATION - VOLTAGE

      Inspection terminals Inspection conditions Standard value
      A13-3 - chassis ground Always 11 to 14V
      G12590954Courtesy of SUBARU OF AMERICA, INC.

      OK: Go to next step

      NG: Repair or replacement of wiring harness or connector

  6. Noise filter check
    1. Check the noise filter. (Refer to INSTALLATION )

      OK: Go to next step

      NG: Repair or replacement of noise filter (Refer to NOISE FILTER )

  7. Check wiring harness and connector (noise filter - stop light switch ASSY)
    1. Disconnect the connector, A22 for the stop light switch ASSY.
    2. Measure the resistance between the terminals.

      Resistance

      Inspection terminals Inspection conditions Standard value
      A13-2 - A22-1 Always Less than 1 Ω
      A13-1 - A22-2 Always Less than 1 Ω

      OK: Go to next step

      NG: Repair or replacement of wiring harness or connector

  8. Stop light switch ASSY check
    1. Check the stop light switch ASSY (Refer to UNIT INSPECTION )

      OK: Go to next step

      NG: Repair or replacement of stop light switch ASSY (Refer to STOP LIGHT SWITCH

  9. Check wiring harness and connector (STP terminal)
    1. Check the connector of the skid control computer (brake actuator ASSY) for a trouble such as poor engagement or disconnection.

      Criteria: No trouble

    2. Turn IG OFF and disconnect the connector A5 from the skid control computer (brake actuator ASSY).
    3. Check the case and terminal of the connector for deformation and/or corrosion.

      Criteria: No deformation or corrosion.

    4. Measure the voltage between the terminals.

      Voltage

      STANDARD VALUE SPECIFICATION

      Inspection terminals Inspection conditions Standard value
      A5-30(STP) - chassis ground Brake pedal, depressed 11 to 14V
      A5-30(STP) - chassis ground Brake pedal, released Less than 1.5 V
      G12590955Courtesy of SUBARU OF AMERICA, INC.

      OK: Go to next step

      NG: Repair or replacement of wiring harness or connector

      Replacement of skid control computer (brake actuator ASSY) (Refer to REMOVAL )

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