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Home >> Lexus >> 2009 >> IS 250 AWD >> Repair and Diagnosis (Single Page) >> Restraints >> Air Bag, SRS >> Occupant Classification System (Diagnostic Codes & Circuit Tests) >> Occupant Classification System >> DTC B1795: Occupant Classification ECU Malfunction >> Procedure
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DTC B1795: Occupant Classification ECU Malfunction: Procedure

  1. CHECK FOR DTC 
    1. Turn the engine 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 engine switch off.
    5. Turn the engine switch on (IG), and wait for at least 10 seconds.
    6. Check for the DTCs. Refer to DTC CHECK / CLEAR .

      OK

      DTC B1795 is not output.

      HINT: 

      Codes other than B1795 may be output at this time, but they are not related to this check.

    OK → See step   4 

    NG: Go to next step 

  2. REPLACE OCCUPANT CLASSIFICATION ECU 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Using the Techstream, save the ECU data from the ECU which has been installed on the vehicle. Refer to REGISTRATION .
    4. Turn the engine switch off.
    5. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    6. Front seat (for power seat)
      1. Replace the occupant classification ECU. Refer to REMOVAL .
    7. Front seat (for manual seat)
      1. Replace the occupant classification ECU. Refer to REMOVAL .
    8. Connect the negative (-) terminal cable to the battery.
    9. Turn the engine switch on (IG).
    10. Using the Techstream, load the previous ECU data stored into the new ECU. Refer to REGISTRATION .
    11. Turn the engine switch off.
    12. Turn the engine switch on (IG).
    13. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .

      HINT: 

      If DTC is not cleared at this time, past DTC will remain.

    NEXT: Go to next step 

  3. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check. Refer to INITIALIZATION .

    NEXT → END 

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