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Occupant Detection System (Diagnostics): Rezero: Operation

NOTE: When any of the following operation has been done, be sure to perform [Rezeroing] of occupant detection system. Ref. to OCCUPANT DETECTION (DIAGNOSTICS)>REZERO .
  • Replacing occupant detection system
  • Removing and disassembling passenger's seat
  • Loosening passenger's seat bolt
CAUTION: When performing [Rezero], the operation must be completed thoroughly.
  1. Park empty vehicle on a level surface.
  2. Check that all harness and connectors are connected.
  3. Check the following items to adjust the condition of the vehicle.
    • Adjust the seat backrest to be fully upright. (For models with power seats, press the power seat button until the backrest comes to a stop.)
    • Do not place anything on the top of the seat cushion.
    • Sit on the seat cushion to smooth the seat surface.
    • Check that the passenger's seat belt is not inserted into the buckle, not tense or not stuck.
    • Check that ambient temperature is in a range from 0 - 40 °C (32 - 104 °F).
  4. Connect the Subaru Select Monitor.
  5. Turn the ignition switch to OFF, then turn it to ON again.
    NOTE:
    • This operation is performed to readjust the standard of occupant detection sensor.
    • Do not touch the seat until the sensor rezero adjustment is completed. If you have touched the seat even if only once, perform operations from the step 3) again.
  6. On [Start] screen, select [Diagnosis].
  7. On [Vehicle selection] screen, input the target vehicle information and select [OK].
  8. On [Main Menu] screen, select [Each System].
  9. On [Select System] screen, select [Occupant Detection].
  10. On [Occupant Detection] screen, select [DTC].
  11. - After replacement of passenger's seat

    Check that no DTC other than DTC B178C is displayed in current malfunction. When B178B is recorded, this means that [Rezero] for passenger's seat was not performed at seat factory. In this case, replace the passenger's seat. When any other DTC is displayed, perform the diagnosis according to the DTC.

    • After replacement of the occupant detection control module

      Check that no DTC other than DTC B178B and B178C is displayed in current malfunction. When DTC other than B178B and B178C is displayed, perform the diagnosis according to the DTC.

    • When collision detection DTC is recorded

    Check that no DTC other than DTC B1783, B1784, B1785 and B1786 is displayed in current malfunction. Perform the diagnosis according to the DTC.

  12. On [Occupant Detection] screen, select [Work Support].
  13. On [Work Support] screen, select [Rezero].
  14. After [See service manual. And check vehicle condition for successfully completing.] is displayed on the screen, check the vehicle condition and select [Next].
  15. When [Rezero] is performed after replacing the occupant detection control module and passenger's seat, [Calibration error has occurred. See service manual.] is displayed on the screen. In this case, check the replacement status described in step 11, and select [Next].
  16. [Rezeroing Adjust the passenger seat to the condition shown in service manual.] is displayed on the screen. Slide the passenger's seat all the way to the front, check that the backrest is adjusted to the most upright position, and select [Next].
    G13872850Courtesy of SUBARU OF AMERICA, INC.
  17. When [Rezeroing Unbelt the passenger seatbelt.] is displayed, make sure the passenger's seat belt is disconnected from the buckle and select [Next].
  18. When [Rezeroing Confirm ambient temperature Between 0 and 40°C. (32 and 104°F)] is displayed on the screen, check that ambient temperature at the seat is in a range from 0 - 40 °C (32 - 104 °F) and select [Next].
  19. When [Rezeroing Empty the passenger seat. Turn ignition OFF, and within 10 seconds, turn ignition ON again.] is displayed on the screen, turn the ignition switch to OFF and then ON again while the passenger's seat is empty, make sure that airbag OFF indicator illuminates and airbag ON indicator does not illuminate, and then select [Next].
    NOTE: After selecting [Next], [In process... Please wait for a while without touching vehicle.] is displayed. Do not touch or rock the vehicle while the message is displayed.
  20. When the sensor rezero adjustment is complete successfully, [Rezeroing is successfully completed. Press "OK" to END.] is displayed. Select [OK].
    NOTE:
    • When [Rezeroing is Unsuccessful.] is displayed during sensor rezero adjustment, select [OK] and perform the process according to the displayed error code. Ref. to OCCUPANT DETECTIONS (DIAGNOSTICS)>Rezero>LIST .
    • When [Diagnostic code check. Some troubles occur. See service manual. Press "OK" to END.] is displayed during sensor rezero adjustment, select [OK] and read DTC of [Occupant Detection]. Ref. to OCCUPANT DETECTIONS (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

    When DTC is displayed, perform the diagnosis according to the DTC, and then perform sensor rezero adjustment. When DTC is not displayed, check the seat and vehicle status and then perform the sensor rezero adjustment again. Ref. to OCCUPANT DETECTION (DIAGNOSTICS)>REZERO .
  21. [Next, execute sensor sensitivity check.] is displayed on the screen. Select [OK].
  22. After [See service manual. And check vehicle condition for successfully completing.] is displayed on the screen, check the vehicle condition.
  23. After [Sensitivity check Adjust the passenger seat to the condition shown in service manual.] is displayed on the screen, check that the passenger's seat does not change from the state confirmed in step 16), and select [Next].
  24. When [Sensitivity check Unbelt the passenger seatbelt.] is displayed, make sure the passenger's seat belt is disconnected from the buckle and select [Next].
  25. When [Sensitivity check Confirm ambient temperature Between 0 and 40°C. (32 and 104° F)] is displayed on the screen, check that ambient temperature at the seat is in a range from 0 - 40 °C (32 - 104 °F) and select [Next].
  26. When [Sensitivity check Empty the passenger seat.] is displayed on the screen, make sure the passenger's seat is empty and select [Next].
  27. After [According to service manual, prepare the weight/SST whose mass is prescribed for sensitivity check, or measure mass of the weight by high-precision electronic scale] is displayed on the screen, prepare an inspection weight of 30 kg to 40 kg in total, and check that there is no dirt or foreign matter on it.
    • If the prepared inspection weight is a weight of which the accuracy has been verified (within ±0.5%), only record the total weight since there is no need of measuring the actual value using a digital scale.
    • If the weight value of prepared weight is not verified or the accuracy is unknown, prepare a digital scale and make sure that there is no dirt or foreign matter on it and that the indication is 0 g (kg) when the power is turned on. Then measure and record the total value.

    Then select [OK].

    NOTE: If 98399AG000 and 98399AG010 are used together, also check that there is no dirt, foreign matter or damage on them, but there is no need of measuring.
  28. When [Input the total mass value of the prepared weight/SST, or input the measured value of measuring the weight. (Unit: kg)] is displayed on the screen, input the mass recorded in step 27) and select [Enter].
    NOTE: If 98399AG000 and 98399AG010 are used together, input the total specified weight value: 35.812 kg.
  29. After [Prepare mass value of the measured weight] is displayed on the screen, check the input value and select [OK].
  30. After [Put the prepared weight on the seat according to service manual.] is displayed on the screen, set the inspection weight on the center of passenger's seat surface, and select [OK].
    NOTE: After selecting [OK], [In process... Please wait for a while without touching vehicle.] is displayed. Do not touch or rock the vehicle while the message is displayed.
  31. When [Sensitivity check is finished. Read Value: **** kg The mass of weight: **** kg] is displayed on the screen after the sensor sensitive inspection is succeeded, select [OK] and turn the ignition switch OFF to exit.
  32. When [Sensitivity check fail. See service manual. Press "OK" to END.] is displayed during sensor sensitive inspection, select [OK] and perform the operation from the beginning. If failure, error code is displayed. Check the error code and fix it. Ref. to OCCUPANT DETECTION (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST .
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