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DTC B1787: Rear Occupant Classification Sensor LH Collision Detection: Procedure

  1. CHECK FOR DTC 
    1. Turn the ignition switch to ON, and wait for at least 60 seconds.
    2. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    3. Turn the ignition switch off.
    4. Turn the ignition switch to ON, and wait for at least 60 seconds.
    5. Check for DTCs. Refer to DTC CHECK / CLEAR .

      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 .

      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 .

      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 .
    2. Turn the ignition switch off.
    3. Turn the ignition switch to ON, and wait for at least 60 seconds.
    4. Check for DTCs. Refer to DTC CHECK / CLEAR .

      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. REPLACE SEPARATE TYPE FRONT SEAT CUSHION SPRING ASSEMBLY RH 
    1. Turn the ignition switch off.
    2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
    3. Replace the separate type front seat cushion spring RH. Refer to DISASSEMBLY .

      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 (-) battery terminal, and wait for at least 2 seconds.
    2. Turn the ignition switch to ON.
    3. Perform the zero point calibration. Refer to INITIALIZATION .

      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 .

      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 .

      HINT: 

      • First clear the DTCs stored in the occupant classification ECU, and then clear the DTCs stored in the center airbag sensor.
      • Use the Techstream to clear the DTCs of the occupant classification ECU, otherwise the DTCs cannot be cleared.
    2. Turn the ignition switch off.
    3. Turn the ignition switch to ON, and wait for at least 60 seconds.
    4. Check for DTCs. Refer to DTC CHECK / CLEAR .

      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 (SEPARATE TYPE FRONT SEAT CUSHION SPRING RH IS DEFECTIVE) 

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

      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 (-) battery terminal, and wait for at least 2 seconds.
    2. Turn the ignition switch to ON.
    3. Perform the zero point calibration. Refer to INITIALIZATION .

      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 .

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

    NEXT → END (OCCUPANT CLASSIFICATION ECU IS DEFECTIVE) 

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