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Power Seat Control System: Inspection

WARNING: This page is about a different car, the 2005 Lexus GS 430 and 2005 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT DRIVER'S POWER SEAT SWITCH CONTINUITY 

    Slide switch: 

    SLIDE SWITCH CONTINUITY CHECK

    Switch position Tester connection Specified condition
    FRONT 1 - 9
    4 - 6    		 Continuity
    OFF 4 - 6
    4 - 9    		 Continuity
    BACK 1 - 6
    4 - 9    		 Continuity

    Front vertical switch: 

    FRONT VERTICAL SWITCH CONTINUITY CHECK

    Switch position Tester connection Specified condition
    UP 1 - 10
    4 - 5    		 Continuity
    OFF 4 - 5
    4 - 10    		 Continuity
    DOWN 1 - 5
    4 - 10    		 Continuity

    Lifter switch: 

    LIFTER SWITCH CONTINUITY CHECK

    Switch position Tester connection Specified condition
    UP 1 - 7
    4 - 8    		 Continuity
    OFF 4 - 7
    4 - 8    		 Continuity
    DOWN 1 - 8
    4 - 7    		 Continuity

    Reclining switch: 

    RECLINING SWITCH CONTINUITY CHECK

    Switch position Tester connection Specified condition
    FORWARD 1 - 3
    2 - 4    		 Continuity
    OFF 2 - 4
    3 - 4    		 Continuity
    REAR 1 - 2
    3 - 4    		 Continuity
    Fig 1: Inspecting Driver'S Power Seat Switch Continuity
    G02940560Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If continuity is not as specified, replace the switch.

  2. INSPECT DRIVER'S POWER SEAT SWITCH CIRCUIT 
    1. Disconnect the switch connector and connect the seat wire harness to the floor wire harness.
    2. Inspect the connector on the wire harness side.
    DRIVER'S POWER SEAT SWITCH CIRCUIT

    Tester connection Condition Specified condition
    4 - Ground Constant Continuity
    1 - Ground Constant Battery positive voltage
    Fig 2: Inspecting Driver's Power Seat Switch Circuit
    G02940561Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If circuit is not as specified, inspect the circuits connected to other parts.

  3. INSPECT PASSENGER'S POWER SEAT SWITCH CONTINUITY 

    Slide switch: 

    SLIDE SWITCH CONTINUITY CHECK

    Switch position Tester connection Specified condition
    FRONT 1 - 9
    4 - 6    		 Continuity
    OFF 4 - 6
    4 - 9    		 Continuity
    BACK 1 - 6
    4 - 9    		 Continuity

    Front vertical switch: 

    FRONT VERTICAL SWITCH CONTINUITY CHECK

    Switch position Tester connection Specified condition
    UP 1 - 5
    4 - 10    		 Continuity
    OFF 4 - 5
    4 - 10    		 Continuity
    DOWN 1 - 10
    4 - 5    		 Continuity

    Lifter switch: 

    LIFTER SWITCH CONTINUITY CHECK

    Switch position Tester connection Specified condition
    UP 1 - 8
    4 - 7    		 Continuity
    OFF 4 - 7
    4 - 8    		 Continuity
    DOWN 1 - 7
    4 - 8    		 Continuity

    Reclining switch: 

    RECLINING SWITCH CONTINUITY CHECK

    Switch position Tester connection Specified condition
    FORWARD 1 - 3
    2 - 4    		 Continuity
    OFF 2 - 4
    3 - 4    		 Continuity
    REAR 1 - 2
    3 - 4    		 Continuity
    Fig 3: Inspecting Passenger Power Seat Switch Continuity
    G02940562Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If continuity is not as specified, replace the switch.

  4. INSPECT PASSENGER'S POWER SEAT SWITCH CIRCUIT 
    1. Disconnect the switch connector and connect the seat wire harness to the floor wire harness.
    2. Inspect the connector on the wire harness side.
    TESTER CONNECTION SPECIFIED CONDITION

    Tester connection Condition Specified condition
    4 - Ground Constant Continuity
    1 - Ground Constant Battery positive voltage
    Fig 4: Identifying Passenger'S Power Seat Switch Connector Terminals
    G02940563Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If circuit is not as specified, inspect the circuits connected to other parts.

  5. INSPECT DRIVER'S LUMBAR SUPPORT SWITCH CONTINUITY 
    DRIVER'S LUMBER SUPPORT SWITCH CONTINUITY CHECK

    Switch position Tester connection Specified condition
    FORWARD 1 - 4
    2 - 3    		 Continuity
    OFF 1 - 3
    2 - 3    		 Continuity
    RELEASE 1 - 3
    2 - 4    		 Continuity
    Fig 5: Inspecting Driver's Lumbar Support Switch Continuity
    G02940564Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If continuity is not as specified, replace the switch.

  6. INSPECT DRIVER'S LUMBAR SUPPORT SWITCH CIRCUIT 
    1. Disconnect the switch connector and connect the seat wire harness to the floor wire harness.
    2. Inspect the connector on the wire harness side.
    DRIVER'S LUMBAR SUPPORT SWITCH CIRCUIT

    Tester connection Condition Specified condition
    3 - Ground Constant Continuity
    4 - Ground Constant Battery positive voltage
    Fig 6: Inspecting Driver's Lumbar Support Switch Circuit
    G02940565Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If circuit is not as specified, inspect the circuits connected to other parts.

  7. INSPECT PASSENGER'S LUMBAR SUPPORT SWITCH CONTINUITY 
    PASSENGER'S LUMBAR SUPPORT SWITCH CONTINUITY

    Switch position Tester connection Specified condition
    FORWARD 1 - 4
    2 - 3    		 Continuity
    OFF 1 - 3
    2 - 3    		 Continuity
    RELEASE 1 - 3
    2 - 4    		 Continuity
    Fig 7: Inspecting Passenger's Lumbar Support Switch Continuity
    G02940566Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If continuity is not as specified, replace the switch.

  8. INSPECT PASSENGER'S LUMBAR SUPPORT SWITCH CIRCUIT 
    1. Disconnect the switch connector and connect the seat wire harness to the floor wire harness.
    2. Inspect the connector on the wire harness side.
    PASSENGER'S LUMBAR SUPPORT SWITCH CIRCUIT

    Tester connection Condition Specified condition
    2 - Ground Constant Continuity
    1 - Ground Constant Battery positive voltage
    Fig 8: Inspecting Passenger's Lumbar Support Switch Circuit
    G02940567Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If circuit is not as specified, inspect the circuits connected to other parts.

  9. INSPECT SLIDE MOTOR OPERATION 
    1. Connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 2, check that the motor turns counterclockwise.
    2. Reverse the polarity, check that the motor turns clockwise.

    If operation is not as specified, replace the seat adjuster.

    Fig 9: Inspecting Slide Motor Operation
    G02940568Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  10. INSPECT SLIDE MOTOR PTC THERMISTOR OPERATION 

    ( ): Passenger side 

    1. Connect the positive (+) lead from the battery to terminal 1 (2), the positive (+) lead from the ammeter to terminal 2 (1) and the negative (-) lead to the battery negative (-) terminal, then move the seat cushion to the front position.
      Fig 10: Connecting Battery To Terminals (Moving Seat Cushion To Front Position)
      G02940569Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Continue to apply voltage, check that current changes to less than 1 ampere within 4 to 90 seconds.
    3. Disconnect the leads from terminals.
    4. Approximately 60 seconds later, connect the positive (+) lead from the battery to terminal 2 (1) and the negative (-) lead to terminal 1 (2), check that the seat cushion begins to move backwards.

    If operation is not as specified, replace the seat adjuster.

    Fig 11: Connecting Battery To Terminals (Moving Seat Cushion Backwards)
    G02940570Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  11. INSPECT FRONT VERTICAL MOTOR OPERATION 
    1. Connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 2, check that the motor turns counterclockwise.
    2. Reverse the polarity, check that the motor turns clockwise.

    If operation is not as specified, replace the seat adjuster.

    Fig 12: Inspecting Front Vertical Motor Operation
    G02940571Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  12. INSPECT FRONT VERTICAL MOTOR PTC THERMISTOR OPERATION 

    ( ): Passenger side 

    1. Connect the positive (+) lead from the battery to terminal 1 (2), the positive (+) lead from the ammeter to terminal 2 (1) and the negative (-) lead to the battery negative (-) terminal, then move the seat cushion to the highest position.
    2. Continue to apply voltage, check that the current changes to less than 1 ampere within 4 to 90 seconds.
      Fig 13: Connecting Battery To Terminals (Moving Seat Cushion To Highest Position)
      G02940572Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the leads from the terminals.
    4. Approximately 60 seconds later, connect the positive (+) lead from the battery to terminal 2 (1) and the negative (-) lead to terminal 1 (2), check that the seat cushion begins to descend.

    If operation is not as specified, replace the seat adjuster.

    Fig 14: Connecting Battery To Terminals (Moving Seat Cushion Begins To Descend)
    G02940573Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  13. INSPECT LIFTER MOTOR OPERATION 
    1. Connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 2, check that the motor turns counterclockwise.
    2. Reverse the polarity, check that the motor turns clockwise.

    If operation is not as specified, replace the seat adjuster. 

    Fig 15: Inspecting Lifter Motor Operation
    G02940574Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  14. INSPECT LIFTER MOTOR PTC THERMISTOR OPERATION 
    1. Connect the positive (+) lead from the battery to terminal 2 (1), the positive (+) lead from the ammeter to terminal 1 (2) and the negative (-) lead to the battery negative (-) terminal, then move the seat cushion to the highest position.
    2. Continue to apply voltage, check that the current changes to less than 1 ampere within 4 to 90 seconds.
      Fig 16: Connecting Battery To Terminals (Moving Seat Cushion To Highest Point)
      G02940575Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the leads from the terminals.
    4. Approximately 60 seconds later, connect the positive (+) lead from the battery to terminal 1 (2) and the negative (-) lead to terminal 2 (1), check that the seat cushion begins to descend.

    If operation is not as specified, replace the seat adjuster.

    Fig 17: Connecting Battery To Terminals (Moving Seat Cushion Begins To Descend)
    G02940576Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  15. INSPECT RECLINING MOTOR OPERATION 
    1. Connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 2, check that the motor turns counterclockwise.
    2. Reverse the polarity, check that the motor turns clockwise.

    If operation is not as specified, replace the seat adjuster.

    Fig 18: Inspecting Reclining Motor Operation
    G02940577Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  16. INSPECT RECLINING MOTOR PTC THERMISTOR OPERATION 
    1. Connect the positive (+) lead from the battery to terminal 2, the positive (+) lead from the ammeter to terminal 1 and the negative (-) lead to the battery negative (-) terminal, then recline the seat back to the most forward position.
    2. Continue to apply voltage, check that the current changes to less than 1 ampere within 4 to 90 seconds.
      Fig 19: Connecting Battery To Terminals (Reclining Seat Back To Most Forward Position)
      G02940578Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the leads from the terminals.
    4. Approximately 60 seconds later, connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 2, check that the seat back begins to fall backward.

    If operation is not as specified, replace the seat adjuster.

    Fig 20: Connecting Battery To Terminals (Checking Seat Back Begins To Fall Backward)
    G02940579Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  17. INSPECT LUMBAR SUPPORT MOTOR OPERATION 
    1. Connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 2, check that the lumbar support moves to release side.
      Fig 21: Connecting Battery To Terminals (Checking Lumber Support Moving Release Side)
      G02940580Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Reverse the polarity, check that the lumbar support moves forward.

    If operation is not as specified, replace the seat adjuster.

    Fig 22: Checking Lumber Support Moving Forward
    G02940581Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  18. INSPECT LUMBAR SUPPORT MOTOR CIRCUIT BREAKER OPERATION 
    1. Connect the positive (+) lead from the battery to terminal 2 and the negative (-) lead to terminal 1 on the lumbar support motor connector and move the lumbar support to front end position.
      Fig 23: Connecting Battery To Terminals (Moving Lumber Support Moving To Front End Position)
      G02940582Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Continue to apply voltage, check that a circuit breaker operation noise can be heard within 4 to 60 seconds.
    3. Reverse the polarity, check that the lumbar support begins to move release side with in approximately 60 seconds.

    If operation is not as specified, replace the motor.

    Fig 24: Checking Lumbar Support Begins To Move Release Side
    G02940583Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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