OCCUPANT CLASSIFICATION SYSTEM, Diagnostic DTC:B1786

DTC Code DTC Name
B1786 Front Occupant Classification Sensor RH Collision Detection

DESCRIPTION

DTC B1786 is output when the occupant classification ECU receives a collision detection signal sent by the front occupant classification sensor RH if an accident occurs.

DTC B1786 is also output when the front seat assembly RH is subjected to a strong impact, even if an actual accident does not occur.

However, when the occupant classification ECU outputs a collision detection signal, even if the vehicle is not in a collision, DTC B1786 can be cleared by Zero Point Calibration and Sensitivity Check.

Therefore, if DTC B1786 is output, first perform Zero Point Calibration and Sensitivity Check.

DTC No. DTC Detection Condition Trouble Area
B1786

  • Front seat assembly RH malfunction

  • Occupant classification ECU malfunction

  • Front occupant classification sensor RH sensed large load

  • Front seat frame with adjuster assembly RH (Front occupant classification sensor RH)

  • Occupant classification ECU

Tech Tips

When DTC B1650/32 is detected as a result of troubleshooting for the airbag system, check the DTCs stored in the occupant classification ECU. When DTC B1786 is output, perform troubleshooting for the DTC.

WIRING DIAGRAM

A01ELREE06

INSPECTION PROCEDURE

PROCEDURE


  1. PERFORM ZERO POINT CALIBRATION


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Using the GTS, perform Zero Point Calibration Click here.

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

    NG

    REPLACE FRONT SEAT FRAME WITH ADJUSTER ASSEMBLY RH Click here

    OK

  2. PERFORM SENSITIVITY CHECK


    1. Using the GTS, perform Sensitivity Check Click here.

      Standard
      27 to 33 kg (59.5 to 72.8 lb)

    NG

    REPLACE FRONT SEAT FRAME WITH ADJUSTER ASSEMBLY RH Click here

    OK

  3. CHECK DTC


    1. Turn the ignition switch to ON.

    2. Clear the DTCs stored in the occupant classification ECU Click here.

    3. Clear the DTCs stored in the center airbag sensor assembly Click here.

    4. Turn the ignition switch off.

    5. Turn the ignition switch to ON.

    6. Check for DTCs Click here.

      OK
      DTC B1786 is not output.

      Tech Tips

      Codes other than DTC B1786 may be output at this time, but they are not related to this check.


    NG

    REPLACE FRONT SEAT FRAME WITH ADJUSTER ASSEMBLY RH Click here

    OK

    END

  4. REPLACE FRONT SEAT FRAME WITH ADJUSTER ASSEMBLY RH


    1. Turn the ignition switch off.

    2. Disconnect the cable from the negative (-) battery terminal.

    3. Replace the front seat frame with adjuster assembly RH Click here.

      Tech Tips

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


    NEXT

  5. PERFORM ZERO POINT CALIBRATION


    1. Connect the cable to the negative (-) battery terminal.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Using the GTS, perform Zero Point Calibration Click here.

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

    NG

    REPLACE OCCUPANT CLASSIFICATION ECU Click here

    OK

  6. PERFORM SENSITIVITY CHECK


    1. Using the GTS, perform Sensitivity Check Click here.

      Standard
      27 to 33 kg (59.5 to 72.8 lb)

    NG

    REPLACE OCCUPANT CLASSIFICATION ECU Click here

    OK

  7. CHECK DTC


    1. Turn the ignition switch to ON.

    2. Clear the DTCs stored in the occupant classification ECU Click here.

    3. Clear the DTCs stored in the center airbag sensor assembly Click here.

    4. Turn the ignition switch off.

    5. Turn the ignition switch to ON.

    6. Check for DTCs Click here.

      OK
      DTC B1786 is not output.

      Tech Tips

      Codes other than DTC B1786 may be output at this time, but they are not related to this check.


    NG

    REPLACE OCCUPANT CLASSIFICATION ECU Click here

    OK

    END

  8. REPLACE OCCUPANT CLASSIFICATION ECU


    1. Turn the ignition switch off.

    2. Disconnect the cable from the negative (-) battery terminal.

    3. Replace the occupant classification ECU Click here.


    NEXT

  9. PERFORM ZERO POINT CALIBRATION


    1. Connect the cable to the negative (-) battery terminal.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Using the GTS, perform Zero Point Calibration Click here.

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

    NEXT

  10. PERFORM SENSITIVITY CHECK


    1. Using the GTS, perform Sensitivity Check Click here.

      Standard
      27 to 33 kg (59.5 to 72.8 lb)

    NEXT

    END