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Power Seat Control System: Inspection

  1. INSPECT DRIVER'S POWER SEAT SWITCH CONTINUITY 

    Slide switch: 

    SPECIFIED CONDITION CHART

    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: 

    SPECIFIED CONDITION CHART

    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: 

    SPECIFIED CONDITION CHART

    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: 

    SPECIFIED CONDITION CHART

    Switch position Tester connection Specified condition
    FORWARD 1 - 3
    2 - 4    		 Continuity
    OFF 2 - 4
    3 - 4    		 Continuity
    REAR 1 - 2
    3 - 4    		 Continuity

    If continuity is not as specified, replace the switch.

    Fig 1: Inspecting Driver'S Power Seat Switch Continuity
    G03380062Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  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.
      Fig 2: Inspecting Connector On Wire Harness Side
      G03380063Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      SPECIFIED CONDITION CHART

      Tester connection Condition Specified condition
      4 - Ground Always Continuity
      1 - Ground Always Battery Positive Voltage

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

  3. INSPECT PASSENGER'S POWER SEAT SWITCH CONTINUITY 

    Slide switch: 

    SPECIFIED CONDITION CHART

    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: 

    SPECIFIED CONDITION CHART

    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: 

    SPECIFIED CONDITION CHART

    Switch position Tester connection Specified condition
    UP 1 - 8
    4 - 7    		 Continuity
    OFF 4 - 7
    4 - 8    		 Continuity
    DOWN 1 - 7
    A4 - 8    		 Continuity
    Fig 3: Inspecting Passenger'S Power Seat Switch Continuity
    G03380064Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Reclining switch: 

    SPECIFIED CONDITION CHART

    Switch position Tester connection Specified condition
    FORWARD 1 - 3
    2 - 4    		 Continuity
    OFF 2 - 4
    3 - 4    		 Continuity
    REAR 1 - 2
    3 - 4    		 Continuity

    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.
      Fig 4: Inspecting Connector On Wire Harness Side
      G03380065Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      SPECIFIED CONDITION CHART

      Tester connection Condition Specified condition
      4 - Ground Always Continuity
      1 - Ground Always Battery positive voltage

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

  5. 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 5: Inspecting Slide Motor
      G03380066Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. INSPECT SLIDE MOTOR PTC THERMISTOR OPERATION 
    1. ( ): Passenger side

      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.

    2. Continue to apply voltage, check that current changes to less than 1 ampere within 4 to 90 seconds.
      Fig 6: Inspecting Slide Motor PTC Thermistor
      G03380067Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 7: Connecting Positive Lead From Battery To Terminal And Negative Lead To Terminal
      G03380068Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. 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 8: Connecting Positive Lead From Battery To Terminal And Negative Lead To Terminal
      G03380069Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  8. INSPECT FRONT VERTICAL MOTOR PTC THERMISTOR OPERATION 
    1. ( ): Passenger side

      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.

      Fig 9: Inspecting Front Vertical Motor PTC Thermistor
      G03380070Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Continue to apply voltage, check that the current changes to less than 1 ampere within 4 to 90 seconds.
    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 10: Checking Seat Cushion Begins To Descend
      G03380071Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  9. 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 11: Inspecting Lifter Motor
      G03380072Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  10. INSPECT LIFTER MOTOR PTC THERMISTOR OPERATION 
    1. ( ): Passenger side

      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 12: Inspecting Lifter Motor PTC Thermistor
      G03380073Courtesy 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 13: Checking Seat Cushion Begins To Descend
      G03380074Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  11. 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 14: Inspecting Reclining Motor
      G03380075Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  12. 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 15: Reclining Seat Back To Forward Position
      G03380076Courtesy 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 16: Checking Seat Back Begins To Fall Backward
      G03380077Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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