2003 Lexus GX 470FACTORY OEM SERVICE PROCEDURE

Seat Belt: Inspection

  1. INSPECT FRONT SEAT INNER BELT ASSY LH 
    1. Inspect the buckle switch.
      1. Fasten the seat belt (Buckle switch is ON).
      2. Check the continuity or resistance between the terminals.
        Fig 1: Identifying Buckle Switch Terminal
        G03373385Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard: 

        SPECIFIED CONDITION

        Terminal No. Specified Condition
        A-1 <=> A-4 1,330 Ω
        A-1 <=> A-6 Continuity
      3. Release the seat belt (Buckle switch is OFF).
      4. Check the continuity or resistance between the terminals.
        Fig 2: Checking Continuity Or Resistance Between Terminals (Buckle Switch Is OFF)
        G03373386Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard: 

        SPECIFIED CONDITION

        Terminal No. Specified Condition
        A-1 <=> A-4 330 Ω
        A-1 <=> A-6 No continuity

      If the result is not as specified, replace the inner belt assy.

    2. Inspect the circuit for the airbag seat position sensor.
      1. Check the continuity between the terminals of connector A and the connector of the airbag seat position sensor.
        Fig 3: Checking Continuity Between Terminals
        G03373387Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard: 

        SPECIFIED CONDITION

        Terminal No. Specified Condition
        A-5 <=> 1 (Connector of airbag seat position sensor) Continuity
        A-3 <=> 2 (Connector of airbag seat position sensor)

        If the result is not as specified, replace the inner belt assy.

  2. INSPECT FRONT SEAT OUTER BELT ASSY LH 
    NOTE: Do not apply battery voltage to the pretensioner connector. 
    1. Inspect operation of the tension reducer.
      1. Connect the positive (+) lead from the battery to terminal 1 of connector A and the negative (-) lead to terminal 2.
      2. Check that the operating noise that the magnetized solenoid is attracting the plunger is heard.
      3. Check that the rewinding volume of the seat belt increases when the seat belt is pulled out and the battery negative (-) lead is disconnected.

      If the result is not as specified, replace the outer belt assy.

      Fig 4: Inspecting Operation Of Tension Reducer
      G03373388Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. INSPECT FRONT SEAT INNER BELT ASSY RH 
    1. Inspect the buckle switch.
      1. Short the circuit between connector terminals 1 and 3 of the occupation detection sensor (Seat is occupied).
        Fig 5: Identifying Short Circuit Between Connector Terminals 1 & 3
        G03373389Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Fasten the seat belt (Buckle switch is ON).
      3. Check the continuity between the terminals.
        Fig 6: Checking Continuity Between Terminals (Buckle Switch Is ON)
        G03373390Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard: 

        SPECIFIED CONDITION

        Terminal No. Specified Condition
        A-2 <=> A-3 No Continuity
        A-4 <=> A-3 No continuity
        A-2 <=> 1 (Connector of occupation detection sensor) Continuity
        A-3 <=> 3 (Connector of occupation detection sensor) No continuity
        A-4 <=> 3 (Connector of occupation detection sensor) Continuity
      4. Release the seat belt (Buckle switch is OFF).
      5. Check the continuity between the terminals.
        Fig 7: Checking Continuity Between Terminals (Buckle Switch Is OFF)
        G03373391Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard: 

        SPECIFIED CONDITION

        Terminal No. Specified Condition
        A-2 <=> A-3 Continuity
        A-3 <=> A-4 Continuity
        A-2 <=> 1 (Connector of occupation detection sensor) Continuity
        A-3 <=> 3 (Connector of occupation detection sensor) Continuity
        A-4 <=> 3 (Connector of occupation detection sensor) Continuity

        If the result is not as specified, replace the inner belt assy.

    2. Inspect the buckle switch.
      1. Disconnect the occupation detection sensor connector (Seat is not occupied).
        Fig 8: Disconnecting Occupation Detection Sensor Connector
        G03373392Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Fasten the seat belt (Buckle switch is ON).
      3. Check the continuity between the terminals.
        Fig 9: Identifying Fasten Seat Belt (Buckle Switch Is ON)
        G03373393Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard: 

        SPECIFIED CONDITION

        Terminal No. Specified Condition
        A-2 <=> A-3 No continuity
        A-4 <=> A-3 No continuity
        A-2 <=> 1 (Connector of occupation detection sensor) Continuity
        A-3 <=> 3 (Connector of occupation detection sensor) No continuity
        A-4 <=> 3 (Connector of occupation detection sensor) Continuity
      4. Release the seat belt (Buckle switch is OFF).
      5. Check the continuity between the terminals.
        Fig 10: Checking Continuity Between Terminals (Buckle Switch Is OFF)
        G03373394Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard: 

        SPECIFIED CONDITION

        Terminal No. Specified Condition
        A-2 <=> A-3 No continuity
        A-3 <=> A-4 Continuity
        A-2 <=> 1 (Connector of occupation detection sensor) Continuity
        A-3 <=> 3 (Connector of occupation detection sensor) Continuity
        A-4 <=> 3 (Connector of occupation detection sensor) Continuity

        If the result is not as specified, replace the inner belt assy.

  4. INSPECT FRONT SEAT OUTER BELT ASSY RH 
    NOTE: Do not apply battery voltage to the pretensioner connector. 
    1. Inspect operation of the tension reducer.
      1. Connect the positive (+) lead from the battery to terminal 1 of connector A and the negative (-) lead to terminal 2.
      2. Check that the operating noise the magnetized solenoid attracting the plunger, is heard.
      3. Check that the rewinding volume of the seat belt increases when the seat belt is pulled out and the battery negative (-) lead is disconnected.

        If the result is not as specified, replace the outer belt assy.

        Fig 11: Inspecting Operation Of Tension Reducer Connector
        G03373395Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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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.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.