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Power Seat Control System: Inspection

  1. INSPECT DRIVER'S POWER SEAT SWITCH CONTINUITY 

    Slide switch: 

    DRIVER'S POWER SEAT SWITCH CONTINUITY (SLIDE SWITCH)

    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: 

    DRIVER'S POWER SEAT SWITCH CONTINUITY (FRONT VERTICAL SWITCH)

    Switch position Tester connection Specified condition
    UP 1-10; 4-5 ((1)) Continuity
    OFF 4-5 ((1)); 4-10 ((1)) Continuity
    DOWN 1-5; 4-10 ((1)) Continuity
    (1) w/power seat memory switch

    Lifter switch: 

    DRIVER'S POWER SEAT SWITCH CONTINUITY (LIFTER SWITCH)

    Switch position Tester connection Specified condition
    UP 1-7; 4-8 ((1)) Continuity
    OFF 4-7((1)); 4-8 ((1)) Continuity
    DOWN 1-8; 4-7((1)) Continuity
    (1) w/power seat memory switch

    Reclining switch: 

    DRIVER'S POWER SEAT SWITCH CONTINUITY (RECLINING SWITCH)

    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
    G02946913Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. INSPECT POWER SEAT MEMORY SWITCH 
    POWER SEAT MEMORY SWITCH

    Switch position Tester connection Specified condition
    SET 1-4 Continuity
    SW1 2-4 Continuity
    SW2 3-4 Continuity
    Fig 2: Inspecting Power Seat Memory Switch
    G02946914Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. 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 3: Inspecting Driver's Power Seat Switch Circuit
      G02946915Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    w/o Power seat memory switch: 

    DRIVER'S POWER SEAT SWITCH CIRCUIT (W/O POWER SEAT MEMORY SWITCH)

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

    w/Power seat memory switch: 

    DRIVER'S POWER SEAT SWITCH CIRCUIT (W/POWER SEAT MEMORY SWITCH)

    Tester connection Condition Specified condition
    1 - Ground Always Continuity

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

  4. INSPECT PASSENGER'S POWER SEAT SWITCH CONTINUITY 

    Slide switch: 

    PASSENGER'S POWER SEAT SWITCH CONTINUITY (SLIDE SWITCH)

    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: 

    PASSENGER'S POWER SEAT SWITCH CONTINUITY (FRONT VERTICAL SWITCH)

    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: 

    PASSENGER'S POWER SEAT SWITCH CONTINUITY (LIFTER SWITCH)

    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: 

    PASSENGER'S POWER SEAT SWITCH CONTINUITY (RECLINING SWITCH)

    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 4: Inspecting Passenger's Power Seat Switch Continuity
    G02946916Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If continuity is not as specified, replace the switch.

  5. 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 5: Inspecting Passenger's Power Seat Switch Circuit
      G02946917Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    PASSENGER'S POWER SEAT SWITCH CIRCUIT

    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.

  6. 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 6: Inspecting Slide Motor Operation
    G02946918Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. 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.

      Fig 7: Moving Seat Cushion To Front Position
      G02946919Courtesy 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.
      Fig 8: Checking Seat Cushion Begins To Move Backwards
      G02946920Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  8. 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 9: Inspecting Front Vertical Motor Operation
    G02946921Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  9. 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 10: Moving Seat Cushion To Highest Position
      G02946922Courtesy 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.
      Fig 11: Checking Seat Cushion Begins To Descend
      G02946923Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  10. 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 12: Inspecting Lifter Motor Operation
    G02946924Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  11. 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.

      Fig 13: Moving Seat Cushion To Highest Position
      G02946925Courtesy 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.
      Fig 14: Checking Seat Cushion Begins To Descend
      G02946926Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  12. 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 15: Inspecting Reclining Motor Operation
    G02946927Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  13. 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.
      Fig 16: Reclining Seat Back To Most Forward Position
      G02946928Courtesy 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 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 17: Checking Seat Back Begins To Fall Backward
    G02946929Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  14. INSPECT POWER SEAT CONTROL ECU 
    1. Check power seat control ECU with connector A and B still connected.
      Fig 18: Inspecting Power Seat Control ECU
      G02946930Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    POWER SEAT CONTROL ECU

    Symbols (Terminal No.) Condition Specified condition
    PKB (A-1) - Body ground Parking brake switch ON Blow 2 V
    P (A-2) - Body ground Neutral position switch is P 10-14 V
    SSRS (A-3) - Body ground Slide position sensor OFF -> ON Blow 2 V -> 6.6 V or higher
    SSFV (A-4) - Body ground Front vertical sensor OFF -> ON Blow 2 V -> 6.6 V or higher
    PCVV (A-5) - Body ground Ignition switch ON Blow 8 V
    SLDF (A-6) - Body ground Manual switch (Front slide) OFF -> ON 1 kΩ or higher -> Below 10 Ω
    SLDR (A-8) - Body ground Manual switch (Rear slide) OFF -> ON 1 kΩ or higher -> Below 10 Ω
    MMRY (A-9) - Body ground Memory switch OFF -> ON 10 kΩ or higher -> Below 100 Ω
    RCLF (A-10) - Body ground Manual switch (Rear reclining) OFF -> ON 1 kΩ or higher -> Below 10 Ω
    RDWN (A-11) - Body ground Manual switch (Rear vertical down) OFF -> ON 1 kΩ or higher -> Below 10 Ω
    RCLR (A-12) - Body ground Manual switch (Front reclining) OFF -> ON 1 kΩ or higher -> Below 10 Ω
    IG (A-13) - Body ground Ignition switch ON 10-14 V
    SI (A-14) Communication line -
    DCTY (A-15) - Body ground Door courtesy switch OFF -> ON 10 kΩ or higher -> Below 100 Ω
    SSRR (A-16) - Body ground Reclining position sensor OFF -> ON Blow 1 V -> Blow 2 V
    SSRV (A-17) - Body ground Rear vertical sensor OFF -> ON Blow 2 V -> 6.6 V or higher
    SGND (A-19) - Body ground Always Blow 1 Ω
    SW2 (A-20) - Body ground Memory switch OFF -> ON 10 kΩ or higher -> Below 100 Ω
    SW1 (A-21) - Body ground Memory switch OFF -> ON 10 kΩ or higher - Below 100 Ω
    RUP (A-22) - Body ground Manual switch (Rear vertical up) OFF -> ON 1 kΩ or higher -> Below 10 Ω
    FUP (A-23) - Body ground Manual switch (Front vertical up) OFF -> ON 1 kΩ or higher -> Below 10 Ω
    FDWN (A-24) - Body ground Manual switch (Front vertical down) OFF -> ON 1 kΩ or higher -> Below 10 Ω
    RCL- (B-1) - Body ground Manual switch (Rear reclining) OFF -> ON Blow 1 V -> 10-14 V
    RCL+ (B-2) - Body ground Manual switch (Front reclining) OFF -> ON Blow 1 V -> 10-14 V
    SLD- (B-3) - Body ground Manual switch (Rear slide) OFF -> ON Blow 1 V -> 10-14 V
    SLD+ (B-4) - Body ground Manual switch (Front slide) OFF -> ON Blow 1 V -> 10-14 V
    RRV- (B-5) - Body ground Manual switch (Rear vertical down) OFF -> ON Blow 1 V -> 10-14 V
    RRV+ (B-6) - Body ground Manual switch (Rear vertical up) OFF -> ON Blow 1 V -> 10-14 V
    GND (B-7) - Body ground Always Blow 1 Ω
    +B (B-8) - Body ground Always 10-14 V
    FRV- (B-9) - Body ground Manual switch (Front vertical down) OFF -> ON Blow 1 V -> 10-14 V
    FRV+ (B-10) - Body ground Manual switch (Front vertical up) OFF -> ON Blow 1 V -> 10-14 V
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