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DTC B1785: Front Occupant Classification Sensor LH Collision Detection [06/2015 - ]: Procedure

  1. CHECK DTC 
    1. Turn the power switch on (IG), and wait for at least 60 seconds.
    2. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [06/2015 - ]

      Body Electrical > Occupant Detection > Clear DTCs 

      HINT: 

      • First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the airbag sensor assembly.
      • Use the Techstream to clear the DTCs of the occupant detection ECU, otherwise the DTCs cannot be cleared.
    3. Turn the power switch off.
    4. Turn the power switch on (IG), and wait for at least 60 seconds.
    5. Check for DTCs.

      Refer to DTC CHECK / CLEAR [06/2015 - ]

      Body Electrical > Occupant Detection > Trouble Codes 

      Result

      Result Proceed to
      DTC B1785 is not output A
      DTC B1785 is output B

      HINT: 

      DTCs other than DTC B1785 may be output at this time, but they are not related to this check.

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  DIAGNOSIS SYSTEM [06/2015 - ] 

    Result: 

    B 

    See step  2

  2. PERFORM ZERO POINT CALIBRATION 
    1. Perform the zero point calibration.

      Refer to INITIALIZATION [06/2015 - ]

      Result

      Result Proceed to
      "Zero Point Calibration is complete." is displayed A
      "Zero Point Calibration is complete." is not displayed B

    Result: 

    B 

    See step  5

    Result: 

    A 

    See step  3

  3. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check.

      Refer to INITIALIZATION [06/2015 - ]

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  4

  4. CHECK DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [06/2015 - ]

      Body Electrical > Occupant Detection > Clear DTCs 

      HINT: 

      • First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the airbag sensor assembly.
      • Use the Techstream to clear the DTCs of the occupant detection ECU, otherwise the DTCs cannot be cleared.
    2. Turn the power switch off.
    3. Turn the power switch on (IG), and wait for at least 60 seconds.
    4. Check for DTCs.

      Refer to DTC CHECK / CLEAR [06/2015 - ]

      Body Electrical > Occupant Detection > Trouble Codes 

      Result

      Result Proceed to
      DTC B1785 is not output A
      DTC B1785 is output B

      HINT: 

      DTCs other than DTC B1785 may be output at this time, but they are not related to this check.

    Result: 

    A 

    END 

    Result: 

    B 

    See step  5

  5. REPLACE FRONT SEAT ADJUSTER ASSEMBLY LH (FRONT OCCUPANT CLASSIFICATION SENSOR LH) 
    1. Turn the power switch off.
    2. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds.
    3. Replace the front seat adjuster assembly RH.

      Refer to DISASSEMBLY [06/2015 - ]

      HINT: 

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

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  6

  6. PERFORM ZERO POINT CALIBRATION 
    1. Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.
    2. Turn the power switch on (IG).
    3. Perform the zero point calibration.

      Refer to INITIALIZATION [06/2015 - ]

      Result

      Result Proceed to
      "Zero Point Calibration is complete." is displayed A
      "Zero Point Calibration is complete." is not displayed B

    Result: 

    B 

    See step  9

    Result: 

    A 

    See step  7

  7. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check.

      Refer to INITIALIZATION [06/2015 - ]

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  8

  8. CHECK DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [06/2015 - ]

      Body Electrical > Occupant Detection > Clear DTCs 

      HINT: 

      • First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the airbag sensor assembly.
      • Use the Techstream to clear the DTCs of the occupant detection ECU, otherwise the DTCs cannot be cleared.
    2. Turn the power switch off.
    3. Turn the power switch on (IG), and wait for at least 60 seconds.
    4. Check for DTCs.

      Refer to DTC CHECK / CLEAR [06/2015 - ]

      Body Electrical > Occupant Detection > Trouble Codes 

      Result

      Result Proceed to
      DTC B1785 is not output A
      DTC B1785 is output B

      HINT: 

      DTCs other than DTC B1785 may be output at this time, but they are not related to this check.

    Result: 

    A 

    END (FRONT SEAT ADJUSTER ASSEMBLY RH [FRONT OCCUPANT CLASSIFICATION SENSOR LH] WAS DEFECTIVE) 

    Result: 

    B 

    See step  9

  9. REPLACE OCCUPANT DETECTION ECU 
    1. Turn the power switch off.
    2. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds.
    3. Replace the occupant detection ECU.

      Refer to REMOVAL [06/2015 - 11/2018] , or refer to REMOVAL [11/2018 - ]

      HINT: 

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

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  10

  10. PERFORM ZERO POINT CALIBRATION 
    1. Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds.
    2. Turn the power switch on (IG).
    3. Perform the zero point calibration.

      Refer to INITIALIZATION [06/2015 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  11

  11. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check.

      Refer to INITIALIZATION [06/2015 - ]

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    END (OCCUPANT DETECTION ECU WAS DEFECTIVE) 

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