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Home >> Lexus >> 2013 >> GS 450h >> Repair and Diagnosis (Single Page) >> Restraints >> Air Bag, SRS >> Occupant Classification System (Diagnostic Codes & Symptom Tests) >> Occupant Classification System >> DTC B1787: Rear Occupant Classification Sensor LH Collision Detection >> Procedure
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DTC B1787: Rear Occupant Classification Sensor LH Collision Detection: Procedure

  1. CHECK FOR DTC 
    1. Turn the power switch on (IG), and wait for at least 60 seconds.
    2. Clear the DTCs. Refer to DTC CHECK / CLEAR [03/2012 - ] .
    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 [03/2012 - ] .

      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.

    NG → See step   2 

    OK → See step   12 

  2. PERFORM ZERO POINT CALIBRATION 
    1. Perform the zero point calibration. Refer to INITIALIZATION [03/2012 - ] .

      OK

      "Zero Point Calibration is complete." is displayed.

    NG → See step   5 

    OK: Go to next step 

  3. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check. Refer to INITIALIZATION [03/2012 - ] .

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

    NG → See step   5 

    OK: Go to next step 

  4. CHECK FOR DTC 
    1. Clear the DTCs. Refer to DTC CHECK / CLEAR [03/2012 - ] .
    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 [03/2012 - ] .

      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.

    NG → See step   5 

    OK → END 

  5. CHECK FRONT SEAT ADJUSTER ASSEMBLY RH (REAR 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.

      HINT: 

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

    NEXT: Go to next step 

  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 [03/2012 - ] .

      OK

      "Zero Point Calibration is complete." is displayed.

    NG → See step   9 

    OK: Go to next step 

  7. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check. Refer to INITIALIZATION [03/2012 - ] .

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

    NG → See step   9 

    OK: Go to next step 

  8. CHECK FOR DTC 
    1. Clear the DTCs. Refer to DTC CHECK / CLEAR [03/2012 - ] .

      HINT: 

      • First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the center airbag sensor.
      • 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 [03/2012 - ] .

      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.

    NG → See step   9 

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

  9. CHECK 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 [03/2012 - ] .

      HINT: 

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

    NEXT: Go to next step 

  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 DIAGNOSIS SYSTEM [03/2012 - ] .

      OK

      "Zero Point Calibration is complete." is displayed.

    NEXT: Go to next step 

  11. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check. Refer to INITIALIZATION [03/2012 - ] .

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

    NEXT → END (OCCUPANT DETECTION ECU WAS DEFECTIVE) 

  12. USE SIMULATION METHOD TO CHECK. Refer to  DIAGNOSIS SYSTEM [03/2012 - ]