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Inspection steps

CAUTION: When the skid control computer (brake actuator Assembly) has been replaced, make sure to perform [VDC sensor mid point setting mode]. (Refer to WORK SUPPORT  )
  1. Tire size check
    1. Check the 4 wheel tire size.

      Criteria: Specified size

      NG: Replace with the tire of specified size.

      OK: Go to Next Step

  2. Current Data Display (Wheel speed)
    1. Using SSM3, check the [Current Data Display] of the [Wheel speed] while driving straight at a speed of 10 km/h or more. (Refer to [CURRENT DATA DISPLAY & SAVE]  )
      SSM3 SCREEN: [ABS/VDC SYSTEM]→[CURRENT DATA DISPLAY & SAVE]

      Item name Description/display range Normal value Remarks
      [Wheel Speed FR] Indicates the front right wheel speed.
      Display range: 0 to 326.4 km/h
      When stopping: 0 km/h
      While driving at a stable speed: There is no big change.
      -
      [Wheel Speed FL] Indicates the front left wheel speed.
      Display range: 0 to 326.4 km/h
      When stopping: 0 km/h
      While driving at a stable speed: There is no big change.
      -
      [Wheel Speed RR] Indicates the rear right wheel speed.
      Display range: 0 to 326.4 km/h
      When stopping: 0 km/h
      While driving at a stable speed: There is no big change.
      -
      [Wheel Speed RL] Indicates the rear left wheel speed.
      Display range: 0 to 326.4 km/h
      When stopping: 0 km/h
      While driving at a stable speed: There is no big change.
      -

      Criteria: There is no big difference from the speed meter.

      RESULT

      Result Go to
      OK A
      NG (front side) B
      NG (rear side) C

      B: Go to step  4.

      C: Go to step  12.

      A: Go to Next Step

  3. Diagnostic code list recheck
    1. Using SSM3, clear the diagnostic code. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
    2. Perform a driving test.
    3. Using SSM3 again, check the diagnostic code output. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
      RESULT

      Result Go to
      Normal A
      Error code (front side) B
      Error code (rear side) C

      B: Go to step 4.

      C: Go to step  12.

      A: Malfunction reproduction test (Refer to PROCEDURES FOR MALFUNCTION PHENOMENON SIMULATION )

  4. Speed sensor installation condition check
    1. Check installation condition of the speed sensor.

      Criteria: Properly installed.

      Fig 1: Identifying Speed Sensor Installation Position (Normal And Malfunction)
      G08555313Courtesy of SUBARU OF AMERICA, INC.

      NG: Properly install the speed sensor or replace it.

      OK: Go to Next Step

  5. Speed sensor check
    1. Remove the speed sensor from the relevant wheel and check it for foreign matter adhesion or damage at the tip. (Refer to REMOVAL  )

      Criteria: There is no foreign particles or damage.

      CAUTION: If there is no damage in the speed sensor through this check, do not replace the speed sensor.

      NG: Clean or replace the speed sensor.

      OK: Go to Next Step

  6. Check wiring harness and connector (speed sensor brake actuator Assembly)
    1. Check the connector of the skid control computer (brake actuator Assembly) 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 Assembly).
    3. Disconnect the connector, A12 or A42 of the front speed sensor.
    4. Check the case and terminal of the connector for deformation and/or corrosion.

      Criteria: No deformation or corrosion.

    5. Measure the resistance between the terminals.

      Resistance

      RESISTANCE - RH

      Inspection terminals Inspection conditions Standard value
      A5-16(FR+) - A42-2(FR+) Always Less than 1 Ω
      A5-16(FR+) - chassis ground Always 10 k Ωor more
      A5-4(FR-) - A42-1(FR-) Always Less than 1 Ω
      A5-4(FR-) - chassis ground Always 10 k Ωor more
      RESISTANCE - LH

      Inspection terminals Inspection conditions Standard value
      A5-19(FL+) - A12-2(FL+) Always Less than 1 Ω
      A5-19(FL+) - chassis ground Always 10 k Ωor more
      A5-32(FL-) - A12-1(FL-) Always Less than 1 Ω
      A5-32(FL-) - chassis ground Always 10 k Ωor more

      NG: Repair or replacement of wiring harness or connector

      OK: Go to Next Step

  7. Diagnostic code list recheck
    1. Using SSM3, clear the diagnostic code. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
    2. Perform a driving test.
    3. Using SSM3 again, check the diagnostic code output. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
      RESULT

      Result Go to
      Error code A
      Normal B

      B: Malfunction reproduction test (Refer to PROCEDURES FOR MALFUNCTION PHENOMENON SIMULATION )

      A: Go to Next Step

  8. Replacement of front speed sensor
    1. Replace the relevant speed sensor rotor with error code. (Refer to FRONT AXLE HUB )

      Next

  9. Diagnostic code list recheck
    1. Using SSM3, clear the diagnostic code. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
    2. Perform a driving test.
    3. Using SSM3 again, check the diagnostic code output. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
      RESULT

      Result Go to
      Error code B
      Normal A

      B: Completed

      A: Go to Next Step

  10. Replacement of speed sensor rotor
    1. Replace the relevant speed sensor rotor with error code. (Refer to FRONT AXLE HUB )
      NOTE: The speed sensor rotor is assembled in the front axle hub. Therefore, replace the front axle hub.

      Next

  11. Diagnostic code list recheck
    1. Using SSM3, clear the diagnostic code. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
    2. Perform a driving test.
    3. Using SSM3 again, check the diagnostic code output. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
      RESULT

      Result Go to
      Normal A
      Error code B

      B: Replacement of skid control computer (brake actuator Assembly) (Refer to REMOVAL  )

      A: Completed

  12. Speed sensor installation condition check
    1. Check installation condition of the speed sensor.

      Criteria: Properly installed.

      Fig 2: Identifying Speed Sensor Installation Position (Normal And Malfunction)
      G08555314Courtesy of SUBARU OF AMERICA, INC.

      NG: Properly install the speed sensor or replace it.

      OK: Go to Next Step

  13. Speed sensor check
    1. Remove the speed sensor from the relevant wheel and check it for foreign matter adhesion or damage at the tip. (Refer to REMOVAL  )

      Criteria: There is no foreign particles or damage.

      CAUTION: If there is no damage in the speed sensor through this check, do not replace the speed sensor.

      NG: Clean or replace the speed sensor.

      OK: Go to Next Step

  14. Check wiring harness and connector (speed sensor brake actuator Assembly)
    1. Check the connector of the skid control computer (brake actuator Assembly) 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 Assembly).
    3. Disconnect the connector, G9 or H12 for the rear speed sensor.
    4. Check the case and terminal of the connector for deformation and/or corrosion.

      Criteria: No deformation or corrosion.

    5. Measure the resistance between the terminals.

      Resistance

      RESISTANCE - RH

      Inspection terminals Inspection conditions Standard value
      A5-17(RR+) - G9-2(RR+) Always Less than 1 Ω
      A5-17(RR+) - chassis ground Always 10 k Ωor more
      A5-29(RR-) - G9-1(RR-) Always Less than 1 Ω
      A5-29(RR-) - chassis ground Always 10 k Ωor more
      RESISTANCE - LH

      Inspection terminals Inspection conditions Standard value
      A5-31(RL+) - H12-2(RL+) Always Less than 1 Ω
      A5-31(RL+) - chassis ground Always 10 k Ωor more
      A5-18(RL-) - H12-1(RL-) Always Less than 1 Ω
      A5-18(RL-) - chassis ground Always 10 k Ωor more

      NG: Repair or replacement of wiring harness or connector

      OK: Go to Next Step

  15. Diagnostic code list recheck
    1. Using SSM3, clear the diagnostic code. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
    2. Perform a driving test.
    3. Using SSM3 again, check the diagnostic code output. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
      RESULT

      Result Go to
      Error code A
      Normal B

      B: Malfunction reproduction test (Refer to PROCEDURES FOR MALFUNCTION PHENOMENON SIMULATION )

      A: Go to Next Step

  16. Replacement of rear speed sensor
    1. Replace the relevant rear speed sensor with error code. (Refer to REMOVAL VEHICLE STABILITY CONTROL SYSTEM  )

      Next

  17. Diagnostic code list recheck
    1. Using SSM3, clear the diagnostic code. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
    2. Perform a driving test.
    3. Using SSM3 again, check the diagnostic code output. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
      RESULT

      Result Go to
      Error code A
      Normal B

      B: Completed

      A: Go to Next Step

  18. Replacement of speed sensor rotor
    1. Replace the relevant speed sensor rotor with error code. (Refer to REAR AXLE HUB )
      NOTE: The speed sensor rotor is assembled in the rear axle hub. Therefore, replace the rear axle hub.

      Next

  19. Diagnostic code list recheck
    1. Using SSM3, clear the diagnostic code. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
    2. Perform a driving test.
    3. Using SSM3 again, check the diagnostic code output. (Refer to CHECKING/CLEARING DIAGNOSTIC CODES  )
      RESULT

      Result Go to
      Normal A
      Error code B

      B: Replacement of skid control computer (brake actuator Assembly) (Refer to REMOVAL  )

      A: Completed