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Home >> Toyota >> 2009 >> Prius Base >> 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 power switch ON (IG).
    3. Using the Techstream, perform the 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 the 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 FOR DTC 
    1. Turn the power switch ON (IG).
    2. Clear the DTCs (see DTC CHECK / CLEAR  ).

      HINT:

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

    3. Turn the power switch OFF.
    4. Turn the power switch ON (IG).
    5. Check the DTCs (see DTC CHECK / CLEAR  ).

      OK: DTC B1785 is not output. 

      HINT:

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

    OK: USE SIMULATION METHOD TO CHECK 

    NG: Go to next step. 

  4. REPLACE FRONT SEAT ASSEMBLY RH 
    1. Turn the power switch OFF.
    2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
    3. Replace the front seat RH (see REMOVAL ).

      HINT:

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

  5. PERFORM ZERO POINT CALIBRATION 
    1. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
    2. Connect the Techstream to the DLC3.
    3. Turn the power switch ON (IG).
    4. Using the Techstream, perform the 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 the 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 FOR DTC 
    1. Turn the power switch ON (IG).
    2. Clear the DTCs (see DTC CHECK / CLEAR  ).

      HINT:

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

    3. Turn the power switch OFF.
    4. Turn the power switch ON (IG).
    5. Check the DTCs (see DTC CHECK / CLEAR  ).

      OK: DTC B1785 is not output. 

      HINT:

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

    OK: USE SIMULATION METHOD TO CHECK 

    NG: Go to next step. 

  8. REPLACE OCCUPANT CLASSIFICATION ECU 
    1. Turn the power switch OFF.
    2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
    3. Replace the occupant classification ECU.
  9. PERFORM ZERO POINT CALIBRATION 
    1. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
    2. Connect the Techstream to the DLC3.
    3. Turn the power switch ON (IG).
    4. Using the Techstream, perform the zero point calibration (see INITIALIZATION  ).

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

  10. PERFORM SENSITIVITY CHECK 
    1. Using the Techstream, perform the sensitivity check (see INITIALIZATION  ).

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

    NEXT: END 

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