FRONT POWER SEAT CONTROL SYSTEM(w/ Memory) Power Seat Position is not Memorized

DESCRIPTION

Tech Tips


  • The position control ECU and switch assembly is a collective term for the position control ECU and switch assembly (driver seat) and the position control ECU and switch assembly (front passenger seat).

  • The seat memory switch is a collective term for the seat memory switch (driver door) and the seat memory switch (front passenger door).

  • The outer mirror control ECU assembly is a collective term for the outer mirror control ECU assembly (driver door) and the outer mirror control ECU assembly (front passenger door).

The main body ECU (multiplex network body ECU) receives seat memory switch signals from the outer mirror control ECU assembly via CAN communication. If the SET switch is being pressed when one of the M1, M2 or M3 switches is pressed, or if one of the M1, M2 or M3 switches is pressed within 3 seconds of pressing the SET switch, the main body ECU (multiplex network body ECU) sends a memory request signal to the position control ECU and switch assembly. After receiving the request signal, the position control ECU and switch assembly memorizes the location data of each motor.

WIRING DIAGRAM


  1. Driver Seat

    A01VW0YE20

  2. Front Passenger Seat

    A01VW0YE21

CAUTION / NOTICE / HINT

Note


  • The seat position will not be stored if the SET switch and 2 or more of the seat memory switches (for example, M1 switch and M2 switch) are pressed simultaneously.

    If a memorizing operation has failed, release all of the switches. The seat memory function will not operate unless the switches are released.

  • The seat will not return to the memorized position if 2 or more of the seat memory switches (for example, M1 switch and M2 switch) are pressed simultaneously.

    If a restoring operation has failed, release all of the switches. The seat memory restoring function will not operate unless the switches are released.

  • The front power seat control system (w/ Memory) uses the CAN communication system. First, confirm that there are no malfunctions in the CAN communication system. Refer to How to Proceed with Troubleshooting.

    Click here

  • Before replacing the main body ECU (multiplex network body ECU), refer to Service Bulletin.

  • The vehicle battery supplies power to the main body ECU (multiplex network body ECU) via the door control battery. Therefore, before proceeding with troubleshooting, perform an on-vehicle inspection and confirm that the main body ECU (multiplex network body ECU) power source circuit is normal.*

    Click here


    • *: w/o Canister Pump Module with Door Ajar Warning Buzzer Function

PROCEDURE


  1. CHECK FRONT POWER SEAT OPERATION


    1. Check that each function of the power seat operates normally by using the position control ECU and switch assembly (driver seat) or position control ECU and switch assembly (front passenger seat).

      Click here

      Result
      Result Proceed to
      Driver power seat functions do not operate A
      Front passenger power seat functions do not operate B

    B

    CHECK FRONT POWER SEAT CONTROL OPERATION Click here

    A

  2. CHECK FRONT POWER SEAT CONTROL OPERATION


    1. Check that each function of the power seat operates normally by using the position control ECU and switch assembly (driver seat).

      Click here

      OK
      Each function of the power seat operates normally using the position control ECU and switch assembly (driver seat).
      Result
      Proceed to
      OK
      NG

    NG

    GO TO PROBLEM SYMPTOMS TABLE Click here

    OK

  3. READ VALUE USING GTS (SEAT MEMORY SWITCH (DRIVER DOOR))


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Mirror L*1 or Mirror R*2 / Data List.


      • *1: for LHD

      • *2: for RHD

    5. Read the Data List according to the display on the GTS.


      Body Electrical > Mirror L > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Seat Memory Switch1 M1 switch ON or OFF

      ON: M1 switch on

      OFF: M1 switch off

      		 -
      Seat Memory Switch2 M2 switch ON or OFF

      ON: M2 switch on

      OFF: M2 switch off

      		 -
      Seat Memory Switch3 M3 switch ON or OFF

      ON: M3 switch on

      OFF: M3 switch off

      		 -
      Seat Memory Set SW SET switch ON or OFF

      ON: SET switch on

      OFF: SET switch off

      		 -

      Body Electrical > Mirror L > Data List
      Tester Display
      Seat Memory Switch1
      Seat Memory Switch2
      Seat Memory Switch3
      Seat Memory Set SW

      Body Electrical > Mirror R > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Seat Memory Switch1 M1 switch ON or OFF

      ON: M1 switch on

      OFF: M1 switch off

      		 -
      Seat Memory Switch2 M2 switch ON or OFF

      ON: M2 switch on

      OFF: M2 switch off

      		 -
      Seat Memory Switch3 M3 switch ON or OFF

      ON: M3 switch on

      OFF: M3 switch off

      		 -
      Seat Memory Set SW SET switch ON or OFF

      ON: SET switch on

      OFF: SET switch off

      		 -

      Body Electrical > Mirror R > Data List
      Tester Display
      Seat Memory Switch1
      Seat Memory Switch2
      Seat Memory Switch3
      Seat Memory Set SW
      OK
      On the GTS screen, ON or OFF is displayed accordingly.
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT SEAT MEMORY SWITCH (DRIVER DOOR) Click here

    OK

  4. PERFORM ACTIVE TEST USING GTS (BUZZER)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Driver Seat / Active Test.

    5. Perform the Active Test according to the display on the GTS.


      Body Electrical > Driver Seat > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Buzzer Buzzer operation OFF/ON -

      Body Electrical > Driver Seat > Active Test
      Tester Display
      Buzzer
      OK
      Buzzer sounds normally.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE POSITION CONTROL ECU AND SWITCH ASSEMBLY (DRIVER SEAT) Click here

    OK

  5. REPLACE OUTER MIRROR CONTROL ECU ASSEMBLY (DRIVER DOOR)


    1. Replace the outer mirror control ECU assembly (driver door) with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK SEAT POSITION MEMORY AND RESTORING FUNCTION


    1. Check the seat position memory and restoring functions.

      Click here

      OK
      Seat position memory and restoring functions operate normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (OUTER MIRROR CONTROL ECU ASSEMBLY (DRIVER DOOR) WAS DEFECTIVE)

    NG

  7. REPLACE POSITION CONTROL ECU AND SWITCH ASSEMBLY (DRIVER SEAT)


    1. Replace the position control ECU and switch assembly (driver seat) with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  8. CHECK SEAT POSITION MEMORY AND RESTORING FUNCTION


    1. Check the seat position memory and restoring functions.

      Click here

      OK
      Seat position memory and restoring functions operate normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (POSITION CONTROL ECU AND SWITCH ASSEMBLY (DRIVER SEAT) WAS DEFECTIVE)

    NG

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

  9. INSPECT SEAT MEMORY SWITCH (DRIVER DOOR)


    1. Remove the seat memory switch (driver door).

      Click here

    2. Inspect the seat memory switch (driver door).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE SEAT MEMORY SWITCH (DRIVER DOOR) Click here

    OK

  10. CHECK HARNESS AND CONNECTOR (OUTER MIRROR CONTROL ECU ASSEMBLY (DRIVER DOOR) - SEAT MEMORY SWITCH (DRIVER DOOR) - BODY GROUND)


    1. Disconnect the N4*1 or M4*2 outer mirror control ECU assembly (driver door) connector.


      • *1: for LHD

      • *2: for RHD

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      N4-1 (MM) - N5-2 (MMRY) Always Below 1 Ω
      N4-1 (MM) or N5-2 (MMRY) - Body ground Always 10 kΩ or higher
      N4-2 (M1) - N5-8 (1) Always Below 1 Ω
      N4-2 (M1) or N5-8 (1) - Body ground Always 10 kΩ or higher
      N4-3 (M2) - N5-6 (2) Always Below 1 Ω
      N4-3 (M2) or N5-6 (2) - Body ground Always 10 kΩ or higher
      N4-4 (M3) - N5-3 (3) Always Below 1 Ω
      N4-4 (M3) or N5-3 (3) - Body ground Always 10 kΩ or higher
      N4-7 (GND) - Body ground Always Below 1 Ω
      N5-1 (E) - Body ground Always Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      M4-1 (MM) - M5-7 (MRY) Always Below 1 Ω
      M4-1 (MM) or M5-7 (MRY) - Body ground Always 10 kΩ or higher
      M4-2 (M1) - M5-1 (M1) Always Below 1 Ω
      M4-2 (M1) or M5-1 (M1) - Body ground Always 10 kΩ or higher
      M4-3 (M2) - M5-3 (M2) Always Below 1 Ω
      M4-3 (M2) or M5-3 (M2) - Body ground Always 10 kΩ or higher
      M4-4 (M3) - M5-6 (M3) Always Below 1 Ω
      M4-4 (M3) or M5-6 (M3) - Body ground Always 10 kΩ or higher
      M4-7 (GND) - Body ground Always Below 1 Ω
      M5-8 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE OUTER MIRROR CONTROL ECU ASSEMBLY (DRIVER DOOR) Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  11. CHECK FRONT POWER SEAT CONTROL OPERATION


    1. Check that each function of the power seat operates normally by using the position control ECU and switch assembly (front passenger seat).

      Click here

      OK
      Each function of the power seat operates normally using the position control ECU and switch assembly (front passenger seat).
      Result
      Proceed to
      OK
      NG

    NG

    GO TO PROBLEM SYMPTOMS TABLE Click here

    OK

  12. READ VALUE USING GTS (SEAT MEMORY SWITCH (FRONT PASSENGER DOOR))


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Mirror R*1 or Mirror L*2 / Data List.


      • *1: for LHD

      • *2: for RHD

    5. Read the Data List according to the display on the GTS.


      Body Electrical > Mirror R > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Seat Memory Switch1 M1 switch ON or OFF

      ON: M1 switch on

      OFF: M1 switch off

      		 -
      Seat Memory Switch2 M2 switch ON or OFF

      ON: M2 switch on

      OFF: M2 switch off

      		 -
      Seat Memory Switch3 M3 switch ON or OFF

      ON: M3 switch on

      OFF: M3 switch off

      		 -
      Seat Memory Set SW SET switch ON or OFF

      ON: SET switch on

      OFF: SET switch off

      		 -

      Body Electrical > Mirror R > Data List
      Tester Display
      Seat Memory Switch1
      Seat Memory Switch2
      Seat Memory Switch3
      Seat Memory Set SW

      Body Electrical > Mirror L > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Seat Memory Switch1 M1 switch ON or OFF

      ON: M1 switch on

      OFF: M1 switch off

      		 -
      Seat Memory Switch2 M2 switch ON or OFF

      ON: M2 switch on

      OFF: M2 switch off

      		 -
      Seat Memory Switch3 M3 switch ON or OFF

      ON: M3 switch on

      OFF: M3 switch off

      		 -
      Seat Memory Set SW SET switch ON or OFF

      ON: SET switch on

      OFF: SET switch off

      		 -

      Body Electrical > Mirror L > Data List
      Tester Display
      Seat Memory Switch1
      Seat Memory Switch2
      Seat Memory Switch3
      Seat Memory Set SW
      OK
      ON or OFF is displayed on the GTS according to the table above.
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT SEAT MEMORY SWITCH (FRONT PASSENGER DOOR) Click here

    OK

  13. PERFORM ACTIVE TEST USING GTS (BUZZER)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Passenger Seat / Active Test.

    5. Perform the Active Test according to the display on the GTS.


      Body Electrical > Passenger Seat > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Buzzer Buzzer operation OFF/ON -

      Body Electrical > Passenger Seat > Active Test
      Tester Display
      Buzzer
      OK
      Buzzer sounds normally.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE POSITION CONTROL ECU AND SWITCH ASSEMBLY (FRONT PASSENGER SEAT) Click here

    OK

  14. REPLACE OUTER MIRROR CONTROL ECU ASSEMBLY (FRONT PASSENGER DOOR)


    1. Temporarily replace the outer mirror control ECU assembly (front passenger door) with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  15. CHECK SEAT POSITION MEMORY AND RESTORING FUNCTION


    1. Check the seat position memory and restoring functions.

      Click here

      OK
      Seat position memory and restoring functions operate normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (OUTER MIRROR CONTROL ECU ASSEMBLY (FRONT PASSENGER DOOR) WAS DEFECTIVE)

    NG

  16. REPLACE POSITION CONTROL ECU AND SWITCH ASSEMBLY (FRONT PASSENGER SEAT)


    1. Temporarily replace the position control ECU and switch assembly (front passenger seat) with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  17. CHECK SEAT POSITION MEMORY AND RESTORING FUNCTION


    1. Check the seat position memory and restoring functions.

      Click here

      OK
      Seat position memory and restoring functions operate normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (POSITION CONTROL ECU AND SWITCH ASSEMBLY (FRONT PASSENGER SEAT) WAS DEFECTIVE)

    NG

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

  18. INSPECT SEAT MEMORY SWITCH (FRONT PASSENGER DOOR)


    1. Remove the seat memory switch (front passenger door).

      Click here

    2. Inspect the seat memory switch (front passenger door).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE SEAT MEMORY SWITCH (FRONT PASSENGER SEAT) Click here

    OK

  19. CHECK HARNESS AND CONNECTOR (OUTER MIRROR CONTROL ECU ASSEMBLY (FRONT PASSENGER DOOR) - SEAT MEMORY SWITCH (FRONT PASSENGER DOOR) - BODY GROUND)


    1. Disconnect the M4*1 or N4*2 outer mirror control ECU assembly (front passenger door) connector.


      • *1: for LHD

      • *2: for RHD

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      M4-1 (MM) - M5-7 (MRY) Always Below 1 Ω
      M4-1 (MM) or M5-7 (MRY) - Body ground Always 10 kΩ or higher
      M4-2 (M1) - M5-1 (M1) Always Below 1 Ω
      M4-2 (M1) or M5-1 (M1) - Body ground Always 10 kΩ or higher
      M4-3 (M2) - M5-3 (M2) Always Below 1 Ω
      M4-3 (M2) or M5-3 (M2) - Body ground Always 10 kΩ or higher
      M4-4 (M3) - M5-6 (M3) Always Below 1 Ω
      M4-4 (M3) or M5-6 (M3) - Body ground Always 10 kΩ or higher
      M4-7 (GND) - Body ground Always Below 1 Ω
      M5-8 (E) - Body ground Always Below 1 Ω
      for RHD
      Tester Connection Condition Specified Condition
      N4-1 (MM) - N5-2 (MMRY) Always Below 1 Ω
      N4-1 (MM) or N5-2 (MMRY) - Body ground Always 10 kΩ or higher
      N4-2 (M1) - N5-8 (1) Always Below 1 Ω
      N4-2 (M1) or N5-8 (1) - Body ground Always 10 kΩ or higher
      N4-3 (M2) - N5-6 (2) Always Below 1 Ω
      N4-3 (M2) or N5-6 (2) - Body ground Always 10 kΩ or higher
      N4-4 (M3) - N5-3 (3) Always Below 1 Ω
      N4-4 (M3) or N5-3 (3) - Body ground Always 10 kΩ or higher
      N4-7 (GND) - Body ground Always Below 1 Ω
      N5-1 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE OUTER MIRROR CONTROL ECU ASSEMBLY (FRONT PASSENGER DOOR) Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR