FRONT POWER SEAT CONTROL SYSTEM Power Seat does not Return to Memorized Position

DESCRIPTION

When either the M1, M2 or M3 switch is pressed, the front multiplex network door ECU LH sends a switch signal to the main body ECU (multiplex network body ECU) via CAN communication. Then, the main body ECU (multiplex network body ECU) sends a recall request signal to the position control ECU assembly LH. The position control ECU assembly LH operates each motor to achieve each memorized position value.

WIRING DIAGRAM

B000PTZE03

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 switches. The seat memory function does 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 switches. The seat memory restoring function does not operate unless the switches are released.

  • The front power seat control system 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.

  • Initializing the position control ECU assembly will clear the seat position memory.

Tech Tips


  • Make sure to initialize the position control ECU assembly after replacing the seat assembly or any related parts (including removal and installation).

  • Before initializing the seat ECU, make sure that the D/C CUT fuse is normal.

  • When any of the following conditions are met, the seat position Information in the position control ECU assembly will be cleared.


    • The power switch is turned off with any of the seat switches being operated and the D/C CUT fuse removed.

    • The power switch is turned off within 1 second of any of the seat switches being operated with the D/C CUT fuse removed.

PROCEDURE


  1. CHECK FRONT POWER SEAT CONTROL OPERATION


    1. Check that each function of the power seat operates normally by using the front power seat switch (for Driver Seat).

      Click here

      OK
      Each function of the power seat operates normally using the front power seat switch (for Driver Seat).
      Result
      Proceed to
      OK
      NG

    NG

    GO TO PROBLEM SYMPTOMS TABLE Click here

    OK

  2. CHECK SEAT POSITION MEMORY FUNCTION


    1. Check that the seat position memory function.

      Click here

      OK
      Seat position memory function is normal.
      Result
      Proceed to
      OK
      NG

    NG

    GO TO OTHER DIAGNOSTIC PROCEDURE (Power Seat Position is not Memorized) Click here

    OK

  3. CHECK SEAT POSITION RESTORING FUNCTION


    1. Under each of the following conditions, check that the seat position restoring function operates by pressing the M1, M2 or M3 switch.

      Click here


      • The power switch is on (IG), and the shift lever is in P.*1

      • The power switch is turned off within 180 seconds after the driver door is closed and opened.*2

      • The power switch is turned off within 60 seconds after the driver door is opened and closed.*3

      Result
      Result Proceed to
      Seat position restoring function does not operate at all. A
      Seat position restoring function does not operate when the condition is *1. B

      • Seat position restoring function does not operate when the condition is *2.

      • Seat position restoring function does not operate when the condition is *3.

      		 C

    B

    READ VALUE USING GTS (SHIFT SW POSITION) Click here

    C

    READ VALUE USING GTS (FR DOOR COUTESY SW, FL DOOR COUTESY SW) Click here

    A

  4. READ VALUE USING GTS (SEAT MEMORY No1, SEAT MEMORY No2, SEAT MEMORY No3)


    1. Store a seat position in memory for each of the M1, M2 and M3 switches.

      Click here

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Turn the GTS on.

    5. Enter the following menus: Body Electrical / Driver Seat / Data List.

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


      Body Electrical > Driver Seat > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Seat Memory No1 Seat position memorized with M1 switch Mem or Not Mem

      Mem: Memorized

      Not Mem: Not memorized

      		 -
      Seat Memory No2 Seat position memorized with M2 switch Mem or Not Mem

      Mem: Memorized

      Not Mem: Not memorized

      		 -
      Seat Memory No3 Seat position memorized with M3 switch Mem or Not Mem

      Mem: Memorized

      Not Mem: Not memorized

      		 -

      Body Electrical > Driver Seat > Data List
      Tester Display
      Seat Memory No1
      Seat Memory No2
      Seat Memory No3
      OK
      Mem appears on the GTS screen.
      Result
      Proceed to
      OK
      NG

    NG

    GO TO OTHER DIAGNOSTIC PROCEDURE (Power Seat Position is not Memorized) Click here

    OK

  5. REPLACE FRONT MULTIPLEX NETWORK DOOR ECU (FOR DRIVER SEAT)


    1. Temporarily replace the front multiplex network door ECU (for Driver Seat) with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK SEAT POSITION MEMORY AND RESTORING FUNCTION


    1. Check that the seat position memory and restoring function.

      Click here

      OK
      Seat position memory and restoring function operates normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (FRONT MULTIPLEX NETWORK DOOR ECU (FOR DRIVER SEAT) WAS DEFECTIVE)

    NG

  7. REPLACE POSITION CONTROL ECU ASSEMBLY (FOR DRIVER SEAT)


    1. Temporarily replace the position control ECU assembly (for 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 that the seat position memory and restoring function.

      Click here

      OK
      Seat position memory and restoring function operates normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (POSITION CONTROL ECU ASSEMBLY (FOR DRIVER SEAT) WAS DEFECTIVE)

    NG

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

  9. READ VALUE USING GTS (SHIFT SW POSITION)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (READY).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Driver Seat / Data List.

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


      Body Electrical > Driver Seat > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Shift SW Position Park state signal Shift P or Shift Other

      Shift P: Shift lever in P

      Shift Other: Shift lever in a position other than P

      		 -

      Body Electrical > Driver Seat > Data List
      Tester Display
      Shift SW Position
      OK
      On the GTS screen, the item changes between ON and OFF according to the above.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POSITION CONTROL ECU ASSEMBLY (FOR DRIVER SEAT) Click here

    NG

    GO TO HYBRID CONTROL SYSTEM Click here

  10. READ VALUE USING GTS (FR DOOR COUTESY SW, FL DOOR COUTESY SW)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Main Body / Data List.

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


      Body Electrical > Main Body > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      FR Door Lock Pos Front door courtesy light switch assembly RH signal ON or OFF

      ON: Driver door open

      OFF: Driver door closed

      		 for RHD
      FL Door Courtesy SW Front door courtesy light switch assembly LH signal ON or OFF

      ON: Driver door open

      OFF: Driver door closed

      		 for LHD

      Body Electrical > Main Body > Data List
      Tester Display
      FR Door Courtesy SW
      FL Door Courtesy SW
      OK
      On the GTS screen, the item changes between ON and OFF according to the above.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POSITION CONTROL ECU ASSEMBLY (FOR DRIVER SEAT) Click here

    NG

    GO TO LIGHTING SYSTEM (Door Courtesy Switch Circuit) Click here