DTC B1786: Front Occupant Classification Sensor RH Collision Detection: Procedure

2012 Toyota Prius ThreeSECTION 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 Zero Point Calibration. Refer to INITIALIZATION .

      OK

      "Zero Point Calibration is complete." is displayed.

    NG → See step   3 

    OK: Go to next step 

  2. CHECK DTC 
    1. Turn the power switch on (IG).
    2. Clear the DTCs stored in the occupant classification ECU. Refer to DTC CHECK / CLEAR .
    3. Clear the DTCs stored in the center airbag sensor assembly. Refer to DTC CHECK / CLEAR .
    4. Turn the power switch off.
    5. Turn the power switch on (IG).
    6. Check for DTCs. Refer to DTC CHECK / CLEAR .

      OK

      DTC B1786 is not output.

      HINT: 

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

      RESULT

      Result Proceed to
      NG A
      OK B

    B → See step   5 

    A: Go to next step 

  3. REPLACE FRONT SEAT CUSHION SPRING ASSEMBLY 
    1. Turn the power switch off.
    2. Disconnect the cable from the negative (-) battery terminal.
    3. Replace the front seat cushion spring assembly. Refer to DISASSEMBLY .

    NEXT: Go to next step 

  4. PERFORM ZERO POINT CALIBRATION 
    1. Connect the cable to the negative (-) battery terminal.
    2. Connect the Techstream to the DLC3.
    3. Turn the power switch on (IG).
    4. Using the Techstream, perform Zero Point Calibration. Refer to INITIALIZATION .

      OK

      "Zero Point Calibration is complete." is displayed.

    NEXT: Go to next step 

  5. PERFORM SENSITIVITY CHECK 
    1. Using the Techstream, perform Sensitivity Check. Refer to INITIALIZATION .

      Standard

      27 to 33 kg (59.5 to 72.8 lb)

    NEXT → END 

RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
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  • • You are missing required tools, torque specs, or safe lifting equipment.
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