LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2020 >> LC 500h >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Seats >> Front Power Seat Control System - Symptom Tests (2 Of 2) >> Front Power Seat Control System >> One-touch Walk-in Function does not Operate [01/2017 - ] >> Procedure

One-touch Walk-in Function does not Operate [01/2017 - ]: Procedure

  1. CHECK SEAT BELT TENSION REDUCER SYSTEM 
    1. Check the seat belt tension reducer system.

      OK

      Seat belt tension reducer system is normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO SEAT BELT TENSION REDUCER SYSTEM. Refer to  PROBLEM SYMPTOMS TABLE [01/2017 - ] 

    Result: 

    OK 

    See step  2

  2. CHECK FOR DTC (ELECTRONIC SHIFT LEVER SYSTEM) 
    1. Perform "DTC Output Confirmation Operation" procedure.

      Refer to DTC CHECK / CLEAR [01/2017 - ]

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [01/2017 - ]

      Powertrain > Hybrid Control > Trouble Codes 

      OK

      DTC is not output.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO ELECTRONIC SHIFT LEVER SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [01/2017 - ] 

    Result: 

    OK 

    See step  3

  3. CHECK FRONT POWER SEAT OPERATION 
    1. Check that each function of the power seat operates normally by using the front power seat switch.

      Refer to OPERATION CHECK [01/2017 - 04/2020] , or refer to OPERATION CHECK [04/2020 - ]

      Result

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

    Result: 

    B 

    See step  11

    Result: 

    A 

    See step  4

  4. READ VALUE USING TECHSTREAM (SHIFT SW POSITION) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Driver Seat / Data List.
    5. Read the Data List according to the display on the Techstream.

      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

      The Techstream display changes correctly in response to the shift lever position.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE POSITION CONTROL ECU ASSEMBLY LH. Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    OK 

    See step  5

  5. READ VALUE USING TECHSTREAM (OPERATION LEVER STATE, SLIDE FRONT OPERATION PERMITTED) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Driver Seat / Data List.
    5. Read the Data List according to the display on the Techstream.

      Body Electrical > Driver Seat > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Operation Lever State Reclining remote control lever sub-assembly state Lock or Unlock Lock: Reclining remote control lever sub-assembly locked
      Unlock: Reclining remote control lever sub-assembly unlocked      		 -
      Slide Front Operation Permitted Forward operation permission state NO or YES NO: Not permitted
      YES: Permitted      		 -

      Body Electrical > Driver Seat > Data List 

      Tester Display
      Operation Lever State
      Slide Front Operation Permitted

      Result

      Result Proceed to
      The value of each Data List item change accordingly. A
      The value of the Data List item "Operation Lever State" not change according to the operation of the reclining remote control lever sub-assembly. B
      The value of the Data List item "Slide Front Operation Permitted" does not change according to the forward operation permission state. C
      The value of each Data List item does not change. D

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [01/2017 - 04/2020]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [04/2020 - 05/2023]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ] 

    Result: 

    C 

    See step  8

    Result: 

    D 

    See step  10

    Result: 

    B 

    See step  6

  6. INSPECT FRONT SEATBACK EDGE PROTECTOR (OUTER LIMIT SWITCH ASSEMBLY) 
    1. Remove the front seatback edge protector (outer limit switch assembly).

      Refer to REMOVAL [01/2017 - 05/2023] , or refer to REMOVAL [05/2023 - ]

    2. Inspect the front seatback edge protector (outer limit switch assembly).

      Refer to INSPECTION [01/2017 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FRONT SEATBACK EDGE PROTECTOR (OUTER LIMIT SWITCH ASSEMBLY). Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY LH - FRONT SEATBACK EDGE PROTECTOR (OUTER LIMIT SWITCH ASSEMBLY)) 
    1. Disconnect the w12 position control ECU assembly LH connector.
    2. Disconnect the w8 front seatback edge protector (outer limit switch assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      w12-2 (FRLS) - w8-1 Always Below 1 Ω
      w12-2 (FRLS) or w8-1 - Other terminals and body ground Always 10 kΩ or higher
      w12-12 (SENG) - w8-2 Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POSITION CONTROL ECU ASSEMBLY LH. Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  8. INSPECT FRONT SEATBACK EDGE PROTECTOR (INNER LIMIT SWITCH ASSEMBLY) 
    1. Remove the front seatback edge protector (inner limit switch assembly).

      Refer to REMOVAL [01/2017 - 05/2023] , or refer to REMOVAL [05/2023 - ]

    2. Inspect the front seatback edge protector (inner limit switch assembly).

      Refer to INSPECTION [01/2017 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FRONT SEATBACK EDGE PROTECTOR (INNER LIMIT SWITCH ASSEMBLY). Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY LH - FRONT SEATBACK EDGE PROTECTOR (INNER LIMIT SWITCH ASSEMBLY)) 
    1. Disconnect the w12 position control ECU assembly LH connector.
    2. Disconnect the y4 front seatback edge protector (inner limit switch assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      w12-16 (LRLS) - y4-1 Always Below 1 Ω
      w12-16 (LRLS) or y4-1 - Other terminals and body ground Always 10 kΩ or higher
      w12-12 (SENG) - y4-2 Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POSITION CONTROL ECU ASSEMBLY LH. Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  10. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY LH - FRONT SEATBACK EDGE PROTECTOR (INNER LIMIT SWITCH ASSEMBLY)) 
    1. Disconnect the w12 position control ECU assembly LH connector.
    2. Disconnect the y4 front seatback edge protector (inner limit switch assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      w12-12 (SENG) - y4-2 Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POSITION CONTROL ECU ASSEMBLY LH. Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  11. READ VALUE USING TECHSTREAM (SHIFT P POSITION STATE) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Passenger Seat / Data List.
    5. Read the Data List according to the display on the Techstream.

      Body Electrical > Passenger 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 > Passenger Seat > Data List 

      Tester Display
      Shift SW Position

      OK

      The Techstream display changes correctly in response to the shift lever position.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE POSITION CONTROL ECU ASSEMBLY RH. Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    OK 

    See step  12

  12. READ VALUE USING TECHSTREAM (OPERATION LEVER STATE AND SLIDE FRONT OPERATION PERMITTED) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Passenger Seat / Data List.
    5. Read the Data List according to the display on the Techstream.

      Body Electrical > Passenger Seat > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Operation Lever State Reclining remote control lever sub-assembly state Lock or Unlock Lock: Reclining remote control lever sub-assembly locked
      Unlock: Reclining remote control lever sub-assembly unlocked      		 -
      Slide Front Operation Permitted Forward operation permission state NO or YES NO: Not permitted
      YES: Permitted      		 -

      Body Electrical > Passenger Seat > Data List 

      Tester Display
      Operation Lever State
      Slide Front Operation Permitted

      Result

      Result Proceed to
      The value of each Data List item change accordingly. A
      The value of the Data List item "Operation Lever State" does not change according to the operation of the reclining remote control lever sub-assembly. B
      The value of the Data List item "Slide Front Operation Permitted" does not change according to the forward operation permission state. C
      The value of each Data List item does not change. D

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [01/2017 - 04/2020]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [04/2020 - 05/2023]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ] 

    Result: 

    C 

    See step  15

    Result: 

    D 

    See step  17

    Result: 

    B 

    See step  13

  13. INSPECT FRONT SEATBACK EDGE PROTECTOR (OUTER LIMIT SWITCH ASSEMBLY) 
    1. Remove the front seatback edge protector (outer limit switch assembly).

      Refer to REMOVAL [01/2017 - 05/2023] , or refer to REMOVAL [05/2023 - ]

    2. Inspect the front seatback edge protector (outer limit switch assembly).

      Refer to INSPECTION [01/2017 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FRONT SEATBACK EDGE PROTECTOR (OUTER LIMIT SWITCH ASSEMBLY). Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    OK 

    See step  14

  14. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY RH - FRONT SEATBACK EDGE PROTECTOR (OUTER LIMIT SWITCH ASSEMBLY)) 
    1. Disconnect the v12 position control ECU assembly RH connector.
    2. Disconnect the v8 front seatback edge protector (outer limit switch assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      v12-2 (FRLS) - v8-1 Always Below 1 Ω
      v12-2 (FRLS) or v8-1 - Other terminals and body ground Always 10 kΩ or higher
      v12-12 (SENG) - v8-2 Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POSITION CONTROL ECU ASSEMBLY RH. Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  15. INSPECT FRONT SEATBACK EDGE PROTECTOR (INNER LIMIT SWITCH ASSEMBLY) 
    1. Remove the front seatback edge protector (inner limit switch assembly).

      Refer to REMOVAL [01/2017 - 05/2023] , or refer to REMOVAL [05/2023 - ]

    2. Inspect the front seatback edge protector (inner limit switch assembly).

      Refer to INSPECTION [01/2017 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FRONT SEATBACK EDGE PROTECTOR (INNER LIMIT SWITCH ASSEMBLY). Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    OK 

    See step  16

  16. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY RH - FRONT SEATBACK EDGE PROTECTOR (INNER LIMIT SWITCH ASSEMBLY)) 
    1. Disconnect the v12 position control ECU assembly RH connector.
    2. Disconnect the x4 front seatback edge protector (inner limit switch assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      v12-16 (LRLS) - x4-1 Always Below 1 Ω
      v12-16 (LRLS) or x4-1 - Other terminals and body ground Always 10 kΩ or higher
      v12-12 (SENG) - x4-2 Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POSITION CONTROL ECU ASSEMBLY RH. Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  17. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU ASSEMBLY RH - FRONT SEATBACK EDGE PROTECTOR (INNER LIMIT SWITCH ASSEMBLY)) 
    1. Disconnect the v12 position control ECU assembly RH connector.
    2. Disconnect the x4 front seatback edge protector (inner limit switch assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      v12-12 (SENG) - x4-2 Always Below 1 Ω
      v12-12 (SENG) or x4-2 - Other terminals and body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POSITION CONTROL ECU ASSEMBLY RH. Refer to  REMOVAL [01/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

scientia non olet · About LEMON Manuals