OCCUPANT CLASSIFICATION SYSTEM, Diagnostic DTC:B1785

DTC Code DTC Name
B1785 Front Occupant Classification Sensor LH Collision Detection

DESCRIPTION

DTC B1785 is stored when the occupant detection ECU receives a collision detection signal sent by the front occupant classification sensor LH if an accident occurs.

DTC B1785 is also stored when the front seat assembly RH is subjected to a strong impact, even if an actual accident does not occur.

If the vehicle was not in a collision, but the occupant detection ECU receives a collision detection signal and stores DTC B1785, the DTC can be cleared by performing Zero Point Calibration and Sensitivity Check.

Therefore, if DTC B1785 is output, first perform Zero Point Calibration and Sensitivity Check.

DTC No. DTC Detection Condition Trouble Area
B1785

  • Front occupant classification sensor LH sensed large load

  • Front seat frame with adjuster assembly RH malfunction

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

WIRING DIAGRAM

Refer to DTC B1780 Click here.

INSPECTION PROCEDURE

Note

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work Click here.

Tech Tips

When DTC B1650/32 is detected as a result of troubleshooting for the airbag system, check for DTCs stored in the occupant detection ECU. When DTC B1785 is output, perform troubleshooting for the DTC.

PROCEDURE


  1. PERFORM ZERO POINT CALIBRATION AND SENSITIVITY CHECK


    1. Using the Techstream, perform Zero Point Calibration and Sensitivity Check Click here.

      OK
      "Zero Point Calibration is complete." and "Sensitivity Check is complete." are displayed.

    NG

    REPLACE FRONT SEAT FRAME WITH ADJUSTER ASSEMBLY RH Click here

    OK

  2. CHECK DTC


    1. Clear the DTCs stored in the occupant detection ECU Click here.

    2. Clear the DTCs stored in the airbag sensor assembly Click here.

    3. Turn the power switch off.

    4. Turn the power switch on (IG).

    5. Check for DTCs Click here.

      OK
      DTC B1785 is not output.

      Tech Tips

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

    6. Turn the power switch off.


    NG

    REPLACE FRONT SEAT FRAME WITH ADJUSTER ASSEMBLY RH Click here

    OK

    END

  3. REPLACE FRONT SEAT FRAME WITH ADJUSTER ASSEMBLY RH


    1. Disconnect the cable from the negative (-) auxiliary battery terminal.

    2. Replace the front seat frame with adjuster assembly RH Click here for Manual Seat, Click here for Power Seat).

    3. Connect the cable to the negative (-) auxiliary battery terminal.


    NEXT

  4. PERFORM ZERO POINT CALIBRATION AND SENSITIVITY CHECK


    1. Using the Techstream, perform Zero Point Calibration and Sensitivity Check Click here.


    NEXT

    END