FRONT POWER SEAT CONTROL SYSTEM (w/ Seat Position Memory System) > One or more Power Seat Motors do not Operate

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DESCRIPTION

When the power seat control switch is operated, a command signal is sent to the position control ECU. The position control ECU then controls the appropriate seat motor as needed. This memory system does not use a seat position sensor. The seat position is detected by counting pulses that are output when the motor turns. If there is no pulse output from the motor, the motor will stop operating. The position control ECU is designed so that a malfunction of the seat memory system will not interfere with manual seat control.

WIRING DIAGRAM


B107930E04


B107940E03


B107930E05


B107940E04


INSPECTION PROCEDURE

1.CHECK FRONT POWER SEAT OPERATION

  1. Check that each function of the power seat operates normally by using the front power seat switches.

    Result: 
    Result
    		Proceed to
    All front power seat switch operations are malfunctioning except lumbar front power seat switch operation
    		A
    Only lumbar front seat switch operation is malfunctioning
    		B



B
Go to step 7
A


2.READ VALUE OF INTELLIGENT TESTER (FRONT POWER SEAT SWITCH)

  1. Check the Data List for proper functioning of the front power seat switch.

    Position control ECU & switch assembly (driver, passenger side):

    Item
    		Measurement Item / Display (Range)
    		Normal Condition
    		Diagnostic Note
    Reclining Rear
    		Reclining switch signal (Rearward) / ON or OFF
    		ON: Reclining switch (Rearward) is ON
    OFF: Reclining switch (Rearward) is OFF
    		-
    Reclining Front
    		Reclining switch signal (Forward) / ON or OFF
    		ON: Reclining switch (Forward) is ON
    OFF: Reclining switch (Forward) is OFF
    		-
    Front Vertical Down
    		Front vertical switch signal (Downward) / ON or OFF
    		ON: Front vertical switch (Downward) is ON
    OFF: Front vertical switch (Downward) is OFF
    		-
    Front Vertical Up
    		Front vertical switch signal (Upward) / ON or OFF
    		ON: Front vertical switch (Upward) is ON
    OFF: Front vertical switch (Upward) is OFF
    		-
    Lifter Switch Down
    		Lifter switch signal (Downward) / ON or OFF
    		ON: Lifter switch (Downward) is ON
    OFF: Lifter switch (Downward) is OFF
    		-
    Lifter Switch Up
    		Lifter switch signal (Upward) / ON or OFF
    		ON: Lifter switch (Upward) is ON
    OFF: Lifter switch (Upward) is OFF
    		-
    Slide Rear
    		Sliding switch signal (Rearward) / ON or OFF
    		ON: Sliding switch (Rearward) is ON
    OFF: Sliding switch (Rearward) is OFF
    		-
    Slide Front
    		Sliding switch signal (Forward) / ON or OFF
    		ON: Sliding switch (Forward) is ON
    OFF: Sliding switch (Forward) is OFF
    		-

    OK:
    On tester screen, each item changes between ON and OFF according to above chart.



NG
REPLACE POSITION CONTROL ECU & SWITCH ASSEMBLY
OK


3.PERFORM ACTIVE TEST BY INTELLIGENT TESTER (POWER SEAT MOTOR)

  1. Select the Active Test, use the intelligent tester to generate a control command, and then check that the power seat motors operate.

    Position control ECU & switch assembly (driver, passenger side):

    Item
    		Test Details
    		Diagnostic Note
    Seat Reclining
    		Seat reclining operation FRONT / REAR
    		-
    Front Vertical Operation
    		Seat front vertical operation UP / DOWN
    		-
    Lifter Operation
    		Seat lifter operation UP / DOWN
    		-
    Seat Slide Operation
    		Seat sliding operation FRONT / REAR
    		-

    OK:
    The power seat motors operate normally.


    Result: 
    Result
    		Proceed to
    NG (LH seat)
    		A
    NG (RH seat)
    		B
    OK
    		C



B
Go to step 5

C
REPLACE POSITION CONTROL ECU & SWITCH ASSEMBLY
A


4.INSPECT FRONT SEAT FRAME WITH ADJUSTER LH (SLIDE MOTOR, FRONT VERTICAL MOTOR, LIFTER MOTOR, RECLINING MOTOR)
B081621E01
B081621E02
B081621E03
B081621E04

  1. Remove the front seat adjuster LH.

  1. Check operation of the slide motor.

    1. Check if the seat adjuster moves smoothly when the battery is connected to the slide motor connector terminals.
      OK: 
      Measurement Condition
      		Operation Direction
      Battery positive (+) → 1
      Battery negative (-) → 2
      		Forward
      Battery positive (+) → 2
      Battery negative (-) → 1
      		Rearward

  1. Check operation of the front vertical motor.

    1. Check if the seat adjuster moves smoothly when the battery is connected to the front vertical motor connector terminals.
      OK: 
      Measurement Condition
      		Operation Direction
      Battery positive (+) → 1
      Battery negative (-) → 2
      		Upward
      Battery positive (+) → 2
      Battery negative (-) → 1
      		Downward

  1. Check operation of the lifter motor.

    1. Check if the seat adjuster moves smoothly when the battery is connected to the lifter motor connector terminals.
      OK: 
      Measurement Condition
      		Operation Direction
      Battery positive (+) → 2
      Battery negative (-) → 1
      		Upward
      Battery positive (+) → 1
      Battery negative (-) → 2
      		Downward

  1. Check operation of the reclining motor.

    1. Check if the seat adjuster moves smoothly when the battery is connected to the reclining motor connector terminals.
      OK: 
      Measurement Condition
      		Operation Direction
      Battery positive (+) → 2
      Battery negative (-) → 1
      		Forward
      Battery positive (+) → 1
      Battery negative (-) → 2
      		Rearward



OK
Go to step 6
NG

REPLACE FRONT SEAT FRAME WITH ADJUSTER LH 

5.INSPECT FRONT SEAT FRAME WITH ADJUSTER RH (SLIDE MOTOR, FRONT VERTICAL MOTOR, LIFTER MOTOR, RECLINING MOTOR)
B081621E01
B081621E02
B081621E03
B081621E04

  1. Remove the front seat adjuster RH.

  1. Check operation of the slide motor.

    1. Check if the seat adjuster moves smoothly when the battery is connected to the slide motor connector terminals.
      OK: 
      Measurement Condition
      		Operation Direction
      Battery positive (+) → 2
      Battery negative (-) → 1
      		Forward
      Battery positive (+) → 1
      Battery negative (-) → 2
      		Rearward

  1. Check operation of the front vertical motor.

    1. Check if the seat adjuster moves smoothly when the battery is connected to the front vertical motor connector terminals.
      OK: 
      Measurement Condition
      		Operation Direction
      Battery positive (+) → 2
      Battery negative (-) → 1
      		Upward
      Battery positive (+) → 1
      Battery negative (-) → 2
      		Downward

  1. Check operation of the lifter motor.

    1. Check if the seat adjuster moves smoothly when the battery is connected to the lifter motor connector terminals.
      OK: 
      Measurement Condition
      		Operation Direction
      Battery positive (+) → 1
      Battery negative (-) → 2
      		Upward
      Battery positive (+) → 2
      Battery negative (-) → 1
      		Downward

  1. Check operation of the reclining motor.

    1. Check if the seat adjuster moves smoothly when the battery is connected to the reclining motor connector terminals.
      OK: 
      Measurement Condition
      		Operation Direction
      Battery positive (+) → 2
      Battery negative (-) → 1
      		Forward
      Battery positive (+) → 1
      Battery negative (-) → 2
      		Rearward



NG
REPLACE FRONT SEAT FRAME WITH ADJUSTER RH
OK


6.CHECK WIRE HARNESS (POSITION CONTROL ECU & SWITCH ASSEMBLY - POWER SEAT MOTOR ASSEMBLY AND BODY GROUND)
B109896E04

  1. Disconnect the d8 or c6 switch connector.

  1. Disconnect the d3, d4, d10, d15, c1, c4, c10 or c15 motor connector.

  1. Measure the resistance of the wire harness side connectors.

    Standard resistance:
    LH seat:
    Tester Connection
    		Specified Condition
    d8-3 (SLD-) - d3-2
    		Below 1 Ω
    d8-2 (SLD+) - d3-1
    		Below 1 Ω
    d8-4 (FRV-) - d4-2
    		Below 1 Ω
    d8-6 (FRV+) - d4-1
    		Below 1 Ω
    d8-9 (LFT-) - d10-1
    		Below 1 Ω
    d8-7 (LFT+) - d10-2
    		Below 1 Ω
    d8-10 (RCL-) - d15-1
    		Below 1 Ω
    d8-8 (RCL+) - d15-2
    		Below 1 Ω
    d8-1 (GND) - Body ground
    		Below 1 Ω
    RH seat:
    Tester Connection
    		Specified Condition
    c6-3 (SLD-) - c1-1
    		Below 1 Ω
    c6-2 (SLD+) - c1-2
    		Below 1 Ω
    c6-4 (FRV-) - c4-1
    		Below 1 Ω
    c6-6 (FRV+) - c4-2
    		Below 1 Ω
    c6-9 (LFT-) - c10-2
    		Below 1 Ω
    c6-7 (LFT+) - c10-1
    		Below 1 Ω
    c6-10 (RCL-) - c15-1
    		Below 1 Ω
    c6-8 (RCL+) - c15-1
    		Below 1 Ω
    c6-1 (GND) - Body ground
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK

REPLACE POSITION CONTROL ECU & SWITCH ASSEMBLY 

7.CHECK WIRE HARNESS (LUMBAR FRONT POWER SEAT SWITCH - LUMBAR FRONT POWER SEAT SWITCH AND BODY GROUND)
B107941E02

  1. Disconnect the d6 or c8 switch connector.

  1. Measure the voltage and resistance of the wire harness side connectors.

    Standard voltage:
    LH seat:
    Tester Connection
    		Specified Condition
    d6-2 (B) - Body ground
    		10 to 14 V
    RH seat:
    Tester Connection
    		Specified Condition
    c8-2 (B) - Body ground
    		10 to 14 V


    Standard resistance:
    LH seat:
    Tester Connection
    		Specified Condition
    d6-1 (E) - Body ground
    		Below 1 Ω
    d6-4 (E2) - Body ground
    		Below 1 Ω
    RH seat:
    Tester Connection
    		Specified Condition
    c8-1 (GND) - Body ground
    		Below 1 Ω
    c8-4 (E) - Body ground
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


8.INSPECT LUMBAR FRONT POWER SEAT SWITCH
B109895E02

  1. Remove the switch.

  1. Measure the resistance between the terminals when the switch is operated.

    Standard resistance:
    LH seat:
    Tester Connection
    		Switch Condition
    		Specified Condition
    2 (B) - 3 (R)
    		HOLD
    		Below 1 Ω
    4 (E2) - 5 (H)
    		HOLD
    		Below 1 Ω
    1 (E) - 3 (R)
    		OFF
    		Below 1 Ω
    5 (H) - 4 (E2)
    		OFF
    		Below 1 Ω
    1 (E) - 3 (R)
    		RELEASE
    		Below 1 Ω
    2 (B) - 5 (H)
    		RELEASE
    		Below 1 Ω
    RH seat:
    Tester Connection
    		Switch Condition
    		Specified Condition
    1 (GND) - 5 (R)
    		HOLD
    		Below 1 Ω
    2 (B) - 3 (H)
    		HOLD
    		Below 1 Ω
    1 (GND) - 5 (R)
    		OFF
    		Below 1 Ω
    3 (H) - 4 (E)
    		OFF
    		Below 1 Ω
    2 (B) - 5 (R)
    		RELEASE
    		Below 1 Ω
    3 (H) - 4 (E)
    		RELEASE
    		Below 1 Ω



NG
REPLACE LUMBAR FRONT POWER SEAT SWITCH
OK


9.INSPECT LUMBAR SUPPORT ADJUSTER ASSEMBLY
B107944E02

  1. Remove the lumbar support adjuster.

  1. Check operation of the lumbar support adjuster.

    1. Check that the lumbar support adjuster moves smoothly when the battery is connected to the lumbar support adjuster motor connector terminals.

      OK:
      Measurement Condition
      		Operation Direction
      Battery positive (+) → 1
      Battery negative (-) → 2
      		Clockwise
      Battery positive (+) → 2
      Battery negative (-) → 1
      		Counterclockwise



NG
REPLACE LUMBAR SUPPORT ADJUSTER ASSEMBLY
OK

REPAIR OR REPLACE HARNESS AND CONNECTOR (LUMBAR FRONT POWER SEAT SWITCH - LUMBAR SUPPORT ADJUSTER ASSEMBLY)