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DTC B1787: Rear Occupant Classification Sensor LH Collision Detection [08/2015 - 08/2019]: Procedure

  1. CHECK FOR DTC 
    1. Turn the engine switch on (IG), and wait for at least 60 seconds.
    2. Clear the DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
    3. Turn the engine switch off.
    4. Turn the engine switch on (IG), and wait for at least 60 seconds.
    5. Check for DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).

      OK

      DTC B1787 is not output.

      HINT: 

      DTCs other than DTC B1787 may be output at this time, but they are not related to this check.

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK 

    (Refer to DIAGNOSIS SYSTEM [08/2015 - ] )

    Result: 

    NG 

    See step  2

  2. PERFORM ZERO POINT CALIBRATION 
    1. Perform the zero point calibration (Refer to INITIALIZATION [08/2015 - ] ).

      OK

      "Zero Point Calibration is complete." is displayed.

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check (Refer to INITIALIZATION [08/2015 - ] ).

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  4

  4. CHECK FOR DTC 
    1. Clear the DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
    2. Turn the engine switch off.
    3. Turn the engine switch on (IG), and wait for at least 60 seconds.
    4. Check for DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).

      OK

      DTC B1787 is not output.

      HINT: 

      DTCs other than DTC B1787 may be output at this time, but they are not related to this check.

    Result: 

    OK 

    END 

    Result: 

    NG 

    See step  5

  5. REPLACE SEPARATE TYPE FRONT SEAT CUSHION SPRING ASSEMBLY RH 
    1. Turn the engine switch off.
    2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
    3. Replace the separate type front seat cushion spring RH (Refer to DISASSEMBLY [08/2015 - 08/2021] ).

      HINT: 

      Perform the inspection using parts from a normal vehicle when possible.

    Result: 

    NEXT 

    See step  6

  6. PERFORM ZERO POINT CALIBRATION 
    1. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
    2. Turn the engine switch on (IG).
    3. Perform the zero point calibration (Refer to INITIALIZATION [08/2015 - ] ).

      OK

      "Zero Point Calibration is complete." is displayed.

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  7

  7. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check (Refer to INITIALIZATION [08/2015 - ] ).

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  8

  8. CHECK FOR DTC 
    1. Clear the DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).

      HINT: 

      • First clear the DTCs stored in the occupant classification ECU, and then clear the DTCs stored in the center airbag sensor.
      • Use the Techstream to clear the DTCs of the occupant classification ECU, otherwise the DTCs cannot be cleared.
    2. Turn the engine switch off.
    3. Turn the engine switch on (IG), and wait for at least 60 seconds.
    4. Check for DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).

      OK

      DTC B1787 is not output.

      HINT: 

      DTCs other than DTC B1787 may be output at this time, but they are not related to this check.

    Result: 

    OK 

    END (SEPARATE TYPE FRONT SEAT CUSHION SPRING RH IS DEFECTIVE) 

    Result: 

    NG 

    See step  9

  9. REPLACE OCCUPANT CLASSIFICATION ECU 
    1. Turn the engine switch off.
    2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
    3. Replace the occupant classification ECU (Refer to REMOVAL [08/2015 - ] ).

      HINT: 

      Perform the inspection using parts from a normal vehicle when possible.

    Result: 

    NEXT 

    See step  10

  10. PERFORM ZERO POINT CALIBRATION 
    1. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
    2. Turn the engine switch on (IG).
    3. Perform the zero point calibration (Refer to INITIALIZATION [08/2015 - ] ).

      OK

      "Zero Point Calibration is complete." is displayed.

    Result: 

    NEXT 

    See step  11

  11. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check (Refer to INITIALIZATION [08/2015 - ] ).

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

    Result: 

    NEXT 

    END (OCCUPANT CLASSIFICATION ECU IS DEFECTIVE)