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DTC B1785: Front Occupant Classification Sensor LH Collision Detection: Procedure

WARNING: This page is about a different car, the 2010 Toyota FJ Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
  1. PERFORM ZERO POINT CALIBRATION 
    1. Connect a Techstream to the DLC3.
    2. Turn the ignition switch to the on position.
    3. Using the Techstream, perform the zero point calibration. Refer toINITIALIZATION .

      OK

      COMPLETED is displayed.

    NG → See step   4 

    OK: Go to next step 

  2. PERFORM SENSITIVITY CHECK 
    1. Using a Techstream, perform the sensitivity check. Refer toINITIALIZATION .

      Standard values

      27 to 33 kg (59.52 to 72.75 lb)

      1. Confirm that nothing is placed on the passenger seat.
      2. Confirm that the beginning sensor reading is within the standard range.

        Standard range

        -3.2 to 3.2 kg (-7 to 7 lb)

      3. Place a 30 kg (66.14 lb) weight (e.g. a lead mass) onto the front passenger seat.
      4. Confirm that the sensitivity is within the standard range.

        Standard range

        27 to 33 kg (59.52 to 72.75 lb)

        HINT: 

        When performing the sensitivity check, use a solid metal weight (the check result may not be accurate if a liquid weight is used).

    NG → See step   4 

    OK: Go to next step 

  3. CHECK DTC 
    1. Turn the ignition switch to the on position.
    2. Clear the DTCs stored in the memory. Refer toDTC CHECK / CLEAR .

      HINT: 

      First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.

    3. Turn the ignition switch to the lock position.
    4. Turn the ignition switch to the on position.
    5. Check the DTCs. Refer toDTC CHECK / CLEAR .

      OK

      DTC B1785 is not output.

      HINT: 

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

    OK → See step   11 

    NG: Go to next step 

  4. REPLACE FRONT SEAT ASSEMBLY RH 
    1. Turn the ignition switch to the lock position.
    2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    3. Replace the front seat assembly RH. Refer toREMOVAL .

      HINT: 

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

    NEXT: Go to next step 

  5. PERFORM ZERO POINT CALIBRATION 
    1. Connect the negative (-) terminal cable to the battery.
    2. Connect a Techstream to the DLC3.
    3. Turn the ignition switch to the on position.
    4. Using the Techstream, perform the zero point calibration. Refer toINITIALIZATION .

      OK

      COMPLETED is displayed.

    NG → See step   8 

    OK: Go to next step 

  6. PERFORM SENSITIVITY CHECK 
    1. Using a Techstream, perform the sensitivity check. Refer toINITIALIZATION .
      1. Confirm that nothing is placed on the passenger seat.
      2. Confirm that the beginning sensor reading is within the standard range.

        Standard range

        -3.2 to 3.2 kg (-7 to 7 lb)

      3. Place a 30 kg (66.14 lb) weight (e.g. a lead mass) onto the front passenger seat.
      4. Confirm that the sensitivity is within the standard range.

        Standard range

        27 to 33 kg (59.52 to 72.75 lb)

        HINT: 

        When performing the sensitivity check, use a solid metal weight (the check result may not be accurate if a liquid weight is used).

    NG → See step   8 

    OK: Go to next step 

  7. CHECK DTC 
    1. Turn the ignition switch to the on position.
    2. Clear the DTCs stored in the memory. Refer toDTC CHECK / CLEAR .

      HINT: 

      First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.

    3. Turn the ignition switch to the lock position.
    4. Turn the ignition switch to the on position.
    5. Check the DTCs. Refer toDTC CHECK / CLEAR .

      OK

      DTC B1785 is not output.

      HINT: 

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

    OK → See step   11 

    NG: Go to next step 

  8. REPLACE OCCUPANT CLASSIFICATION ECU 
    1. Turn the ignition switch to the lock position.
    2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    3. Replace the occupant classification ECU. Refer toREMOVAL .

    NEXT: Go to next step 

  9. PERFORM ZERO POINT CALIBRATION 
    1. Connect the negative (-) terminal cable to the battery.
    2. Connect a Techstream to the DLC3.
    3. Turn the ignition switch to the on position.
    4. Using the Techstream, perform the zero point calibration. Refer toINITIALIZATION .

      OK

      COMPLETED is displayed.

    NEXT: Go to next step 

  10. PERFORM SENSITIVITY CHECK 
    1. Using a Techstream, perform the sensitivity check. Refer toINITIALIZATION .
      1. Confirm that nothing is placed on the passenger seat.
      2. Confirm that the beginning sensor reading is within the standard range.

        Standard range

        -3.2 to 3.2 kg (-7 to 7 lb)

      3. Place a 30 kg (66.14 lb) weight (e.g. a lead mass) onto the front passenger seat.
      4. Confirm that the sensitivity is within the standard range.

        Standard range

        27 to 33 kg (59.52 to 72.75 lb)

        HINT: 

        When performing the sensitivity check, use a solid metal weight (the check result may not be accurate if a liquid weight is used).

    NEXT → END 

  11. USE SIMULATION METHOD TO CHECK. Refer to DIAGNOSIS SYSTEM