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Home >> Toyota >> 2009 >> Sienna CE >> Repair and Diagnosis (Single Page) >> Restraints >> Air Bag, SRS >> Supplemental Restraint System >> Occupant Classification System >> DTC B1785 Front Occupant Classification Sensor LH Collision Detection >> Inspection Procedure
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Inspection Procedure

  1. PERFORM ZERO POINT CALIBRATION 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to the ON position.
    3. Using the Techstream, perform "Zero point calibration" (See INITIALIZATION  ).

      OK: "Zero Point Calibration is complete." is displayed. 

    NG:  Go to step  4

    OK: Go To Next Step 

  2. PERFORM SENSITIVITY CHECK 
    1. Using the Techstream, perform "Sensitivity check" (See INITIALIZATION  ).

      Standard value: 27 to 33 kg (59.52 to 72.75 lb) 

    NG:  Go to 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 (See DTC 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 (See DTC 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: END 

    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 (See REMOVAL for flat type, REMOVAL for manual seat, REMOVAL for power seat).

      HINT:

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

  5. PERFORM ZERO POINT CALIBRATION 
    1. Connect the negative (-) terminal cable to the battery.
    2. Connect the Techstream to the DLC3.
    3. Turn the ignition switch to the ON position.
    4. Using the Techstream, perform "Zero point calibration" (See INITIALIZATION  ).

      OK: "Zero Point Calibration is complete." is displayed. 

    NG:  Go to step  8

    OK: Go To Next Step 

  6. PERFORM SENSITIVITY CHECK 
    1. Using the Techstream, perform "Sensitivity check" (See INITIALIZATION  ).

      Standard value: 27 to 33 kg (59.52 to 72.75 lb) 

    NG:  Go to 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 (See DTC 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 (See DTC 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: END 

    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 (See REMOVAL  ).
  9. PERFORM ZERO POINT CALIBRATION 
    1. Connect the negative (-) terminal cable to the battery.
    2. Connect the Techstream to the DLC3.
    3. Turn the ignition switch to the ON position.
    4. Using the Techstream, perform "Zero point calibration" (See INITIALIZATION  ).

      OK: "Zero Point Calibration is complete." is displayed. 

  10. PERFORM SENSITIVITY CHECK 
    1. Using the Techstream, perform "Sensitivity check" (See INITIALIZATION  ).

      Standard value: 27 to 33 kg (59.52 to 72.75 lb) 

    NEXT: END