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Home >> Lexus >> 2019 >> LS 500 Base, AWD >> Repair and Diagnosis (Single Page) >> Body & Frame >> Seats >> Front Power Seat Control System - Symptom Tests (3 Of 3) >> Front Power Seat Control System >> Wireless Transmitter Memory Function does not Operate [10/2023 - ] >> Procedure
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Wireless Transmitter Memory Function does not Operate [10/2023 - ]: Procedure

  1. CHECK POWER DOOR LOCK CONTROL SYSTEM 
    1. Check the manual lock/unlock function by using the door control switch (multiplex network master switch assembly).

      Refer to OPERATION CHECK [10/2023 - ]

      OK

      Manual lock/unlock function operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO POWER DOOR LOCK CONTROL SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2023 - ] 

    Result: 

    OK 

    See step  2

  2. CHECK SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) 
    1. Check that the engine starts normally when the engine switch is pressed while carrying the key and with the brake pedal depressed.

      Refer to OPERATION CHECK [10/2023 - ]

      OK

      Engine starts normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function). Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2023 - ] 

    Result: 

    OK 

    See step  3

  3. CHECK SEAT POSITION MEMORY AND RESTORING FUNCTION 
    1. Check the seat position memory and restoring function.

      Refer to OPERATION CHECK [10/2023 - ]

      Result

      Result Proceed to
      OK A
      NG (seat position memory function does not operate normally) B
      NG (seat position restoring function does not operate normally) C

    Result: 

    GO TO OTHER DIAGNOSTIC PROCEDURE (Power Seat Position is not Memorized). Refer to  Power Seat Position is not Memorized [10/2023 - ]  

    Result: 

    GO TO OTHER DIAGNOSTIC PROCEDURE (Power Seat does not Return to Memorized Position). Refer to  Power Seat does not Return to Memorized Position [10/2023 - ]  

    Result: 

    See step  4

  4. READ VALUE USING GTS 
    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 / 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
      FL Door Courtesy Switch Status Front door courtesy light switch assembly LH signal Close or Open Close: Front door LH closed
      Open: Front door LH open
      -

      Body Electrical > Main Body > Data List 

      Tester Display
      FL Door Courtesy Switch Status

      OK

      ON or OFF appears on the screen according to the driver door condition.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO LIGHTING SYSTEM (Door Courtesy Switch Circuit). Refer to  Door Courtesy Switch Circuit [10/2023 - ] 

    Result: 

    OK 

    See step  5

  5. CHECK MEMORY CALL FUNCTION (MEMORY REGISTRATION) 
    1. Check the memory registration of the memory call function.

      Refer to OPERATION CHECK [10/2023 - ]

      OK

      Memory registration operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  8

    Result: 

    OK 

    See step  6

  6. READ VALUE USING GTS 
    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 / 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
      MEM Switch No. with Key ID 1 Memory switch linked with key ID1 NONE, D MEM SW1, D MEM SW2 or D MEM SW3 NONE: No switches linked with key ID1
      D MEM SW1: M1 switch linked with key ID1
      D MEM SW2: M2 switch linked with key ID1
      D MEM SW3: M3 switch linked with key ID1
      -
      MEM Switch No. with Key ID 2 Memory switch linked with key ID2 NONE, D MEM SW1, D MEM SW2 or D MEM SW3 NONE: No switches linked with key ID2
      D MEM SW1: M1 switch linked with key ID2
      D MEM SW2: M2 switch linked with key ID2
      D MEM SW3: M3 switch linked with key ID2
      -
      MEM Switch No. with Key ID 3 Memory switch linked with key ID3 NONE, D MEM SW1, D MEM SW2 or D MEM SW3 NONE: No switches linked with key ID3
      D MEM SW1: M1 switch linked with key ID3
      D MEM SW2: M2 switch linked with key ID3
      D MEM SW3: M3 switch linked with key ID3
      -
      MEM Switch No. with Key ID 4 Memory switch linked with key ID4 NONE, D MEM SW1, D MEM SW2 or D MEM SW3 NONE: No switches linked with key ID4
      D MEM SW1: M1 switch linked with key ID4
      D MEM SW2: M2 switch linked with key ID4
      D MEM SW3: M3 switch linked with key ID4
      -
      MEM Switch No. with Key ID 5 Memory switch linked with key ID5 NONE, D MEM SW1, D MEM SW2 or D MEM SW3 NONE: No switches linked with key ID5
      D MEM SW1: M1 switch linked with key ID5
      D MEM SW2: M2 switch linked with key ID5
      D MEM SW3: M3 switch linked with key ID5
      -
      MEM Switch No. with Key ID 6 Memory switch linked with key ID6 NONE, D MEM SW1, D MEM SW2 or D MEM SW3 NONE: No switches linked with key ID6
      D MEM SW1: M1 switch linked with key ID6
      D MEM SW2: M2 switch linked with key ID6
      D MEM SW3: M3 switch linked with key ID6
      -
      MEM Switch No. with Key ID 7 Memory switch linked with key ID7 NONE, D MEM SW1, D MEM SW2 or D MEM SW3 NONE: No switches linked with key ID7
      D MEM SW1: M1 switch linked with key ID7
      D MEM SW2: M2 switch linked with key ID7
      D MEM SW3: M3 switch linked with key ID7
      -

      Body Electrical > Main Body > Data List 

      Tester Display
      MEM Switch No. with Key ID 1
      MEM Switch No. with Key ID 2
      MEM Switch No. with Key ID 3
      MEM Switch No. with Key ID 4
      MEM Switch No. with Key ID 5
      MEM Switch No. with Key ID 6
      MEM Switch No. with Key ID 7

      OK

      A seat position memory switch is linked to the electrical key transmitter sub-assembly.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [10/2023 - ] 

    Result: 

    OK 

    See step  7

  7. CHECK MEMORY CALL FUNCTION (MEMORY REGISTRATION AND AUTOMATIC MEMORY CALL FUNCTION) 
    1. Check the memory registration and automatic memory call function of the memory call function.

      Refer to OPERATION CHECK [10/2023 - ]

      OK

      Memory registration and automatic memory call function operate normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2023 - ] 

    Result: 

    NG 

    GO TO OTHER DIAGNOSTIC PROCEDURE (Wireless-linked Return Function does not Operate). Refer to  Wireless-linked Return Function does not Operate [10/2023 - ]  

  8. REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) 
    1. Replace the main body ECU (multiplex network body ECU) with a new one.

      Refer to REMOVAL [10/2023 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  9

  9. CHECK MEMORY CALL FUNCTION (MEMORY REGISTRATION) 
    1. Check the memory registration of the memory call function.

      Refer to OPERATION CHECK [10/2023 - ]

      OK

      Memory registration operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) WAS DEFECTIVE) 

    Result: 

    NG 

    See step  10

  10. REPLACE POSITION CONTROL ECU ASSEMBLY 
    1. Temporarily replace the position control ECU assembly with a new or known good one.

      Refer to REMOVAL [10/2023 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  11

  11. CHECK MEMORY CALL FUNCTION (MEMORY REGISTRATION) 
    1. Check the memory registration of the memory call function.

      Refer to OPERATION CHECK [10/2023 - ]

      OK

      Memory registration operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

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

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)