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Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

HINT

  1. CHECK CONNECTORS 
    1. Turn the engine switch off.
    2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
    3. Check that the connectors are properly connected to the occupant classification ECU and the center airbag sensor assembly.

      OK: The connectors are properly connected. 

      HINT

      If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.

    4. Disconnect the connectors from the center airbag sensor assembly and the occupant classification ECU.
    5. Check that the terminals of the connectors are not damaged

      OK: The terminals are not deformed or damaged. 

    NG: REPLACE WIRE HARNESS 

    OK: Go to next step 

  2. CHECK OCCUPANT CLASSIFICATION SYSTEM CIRCUIT (SHORT TO B+) 
    1. Connect the cable to the negative (-) battery terminal.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      T16-11 (FSR+) - Body ground Engine switch on (IG) Below 1 V
      T16-12 (FSR-) - Body ground Engine switch on (IG) Below 1 V
      4. Fig 1: Identifying Occupant Classification System Circuit (Short To B+)
      G05757126Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step  12

    OK: Go to next step 

  3. CHECK OCCUPANT CLASSIFICATION SYSTEM CIRCUIT (OPEN) 
    1. Turn the engine switch off.
    2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
    3. Using SST, connect terminals 12 (FSP+) and 13 (FSP-) of connector B.
      NOTE: Do not forcibly insert SST into the terminals of the connector when connecting the wire.

      SST 09843-18040 

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      T16-11 (FSR+) - T16-12 (FSR-) Always Below 1 Ω
      5. Fig 2: Identifying Occupant Classification System Circuit (Open)
      G05757127Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step  13

    OK: Go to next step 

  4. CHECK OCCUPANT CLASSIFICATION SYSTEM CIRCUIT (SHORT) 
    1. Disconnect SST from connector B.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      T16-11 (FSR+) - T16-12 (FSR-) Always 1 MΩ or higher
      3. Fig 3: Identifying Occupant Classification System Circuit (Short)
      G05757128Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step  14

    OK: Go to next step 

  5. CHECK OCCUPANT CLASSIFICATION SYSTEM CIRCUIT (SHORT TO GROUND) 
    1. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      T16-11 (FSR+) - Body ground Always 1 MΩ or higher
      T16-12 (FSR-) - Body ground Always 1 MΩ or higher
      2. Fig 4: Identifying Occupant Classification System Circuit (Short To Ground)
      G05757129Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step  15

    OK: Go to next step 

  6. RECHECK DTC 
    1. Connect the connectors to the occupant classification ECU and the center airbag sensor assembly
    2. Connect the Techstream to the DLC3.
    3. Connect the cable to the negative (-) battery terminal
    4. Turn the engine switch on (IG)
    5. Clear the DTCs stored in the occupant classification ECU (See DTC CHECK / CLEAR  )
    6. Clear the DTCs stored in the center airbag sensor assembly (See DTC CHECK / CLEAR  ).
    7. Turn the engine switch off.
    8. Turn the engine switch on (IG).
    9. Using the Techstream, check for DTCs of the occupant classification ECU (See DTC CHECK / CLEAR  )

      OK: DTC B1790 is not output. 

      HINT

      Codes other than DTC B1790 may be output at this time, but they are not related to this check

    NG: Go to step 7 

    OK: USE SIMULATION METHOD TO CHECK  (See DIAGNOSIS SYSTEM  )

  7. 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 currently installed on the vehicle (See REGISTRATION  )
    4. Turn the engine switch off
    5. Disconnect the cable from the negative (-) battery terminal.
    6. Replace the occupant classification ECU (See REMOVAL  )
    7. Connect the cable to the negative (-) battery terminal
    8. Turn the engine switch on (IG)
    9. Using the Techstream, load the previous ECU data stored into the new ECU (See REGISTRATION  ).
    10. Turn the engine switch off.
    11. Turn the engine switch on (IG)
    12. Clear the DTCs stored in the memory (See DTC CHECK / CLEAR  ).

      HINT

      If the DTCs are not cleared at this time, past DTCs will remain

  8. RECHECK DTC 
    1. Turn the engine switch on (IG).
    2. Clear the DTCs stored in the occupant classification ECU (See DTC CHECK / CLEAR  )
    3. Clear the DTCs stored in the center airbag sensor assembly (See DTC CHECK / CLEAR  )
    4. Turn the engine switch off.
    5. Turn the engine switch on (IG).
    6. Using the Techstream, check for DTCs of the occupant classification ECU (See DTC CHECK / CLEAR  ).

      OK: DTC B1790 is not output. 

      HINT

      Codes other than DTC B1790 may be output at this time, but they are not related to this check.

    NG: Go to step  10

    OK: Go to next step 

  9. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check (See INITIALIZATION  ).

    NEXT: END 

  10. REPLACE CENTER AIRBAG SENSOR ASSEMBLY 
    1. Turn the engine switch off
    2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
    3. Replace the center airbag sensor assembly (See REMOVAL  ).
  11. PERFORM SENSITIVITY CHECK 
    1. Perform the sensitivity check (See INITIALIZATION  ).

    NEXT: END 

  12. CHECK FLOOR WIRE (SHORT TO B+) 
    1. Turn the engine switch off.
    2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
    3. Disconnect the front seat wire RH connector from the floor wire.
    4. Connect the cable to the negative (-) battery terminal.
    5. Turn the engine switch on (IG).
    6. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      PT2-3 (FSR+) - Body ground Engine switch on (IG) Below 1 V
      PT2-8 (FSR-) - Body ground Engine switch on (IG) Below 1 V
      7. Fig 5: Identifying Floor Wire (Short To B+)
      G05757130Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FLOOR WIRE 

    OK: REPLACE FRONT SEAT WIRE RH 

  13. CHECK FLOOR WIRE (OPEN) 
    1. Disconnect the front seat wire RH connector from the floor wire.
      Fig 6: Identifying Floor Wire (Open)
      G05757131Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT

      SST has already been inserted into connector B.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      PT2-3 (FSR+) - PT2-8 (FSR-) Always Below 1 Ω

    NG: REPLACE FLOOR WIRE 

    OK: REPLACE FRONT SEAT WIRE RH 

  14. CHECK FLOOR WIRE (SHORT) 
    1. Disconnect the front seat wire RH connector from the floor wire.
    2. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      PT2-3 (FSR+) - PT2-8 (FSR-) Always 1 MΩ or higher
      3. Fig 7: Identifying Floor Wire (Short)
      G05757132Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FLOOR WIRE 

    OK: REPLACE FRONT SEAT WIRE RH 

  15. CHECK FLOOR WIRE (SHORT TO GROUND) 
    1. Disconnect the front seat wire RH connector from the floor wire.
    2. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      PT2-3 (FSR+) - Body ground Always 1 MΩ or higher
      PT2-8 (FSR-) - Body ground Always 1 MΩ or higher
      3. Fig 8: Identifying Floor Wire (Short To Ground)
      G05757133Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FLOOR WIRE 

    OK: REPLACE FRONT SEAT WIRE RH 

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