DTC B14F5: Overcurrent Detected in Seat Heater: Procedure

2010 Lexus LS 460L AWDSECTION Procedure
  1. CHECK FOR DTC 
    1. Check for DTCs. Refer to DTC CHECK / CLEAR .
      RESULT

      Result Proceed to
      DTC is output (Driver seat climate control ECU) A
      DTC is output (Passenger seat climate control ECU) B
      DTC is output (Rear seat climate control ECU LH) C
      DTC is output (Rear seat climate control ECU RH) D

    D → See step   11 

    C → See step   8 

    B → See step   5 

    A: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (SEAT CLIMATE CONTROL ECU - FRONT SEAT CUSHION COVER LH) 
    1. Disconnect the e35 ECU connector.
      Fig 1: Checking Harness And Connector (Seat Climate Control ECU - Front Seat Cushion Cover LH)
      GTY288716Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the e42 cushion cover connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      e35-1 (B) - e42-2 (B) Always Below 1 Ω
      e35-1 (B) - Body ground Always 10 kΩ or higher
      e35-5 (E) - e42-4 (E) Always Below 1 Ω
      e35-5 (E) - Body ground Always 10 kΩ or higher
      e35-1 (B) - e35-5 (E) Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. CHECK SEAT CLIMATE CONTROL ECU (OPERATION) 
    1. Replace the seat climate control ECU with a new one or normally operating one, and check if a DTC is output.

      OK

      DTC is not output

    NG → See step   14 

    OK → See step   4 

  4. REPLACE SEAT CLIMATE CONTROL ECU. Refer to  DISASSEMBLY 
  5. CHECK HARNESS AND CONNECTOR (SEAT CLIMATE CONTROL ECU - FRONT SEAT CUSHION COVER RH) 
    1. Disconnect the e3 ECU connector.
      Fig 2: Checking Harness & Connector (Seat Climate Control ECU - Front Seat Cushion Cover RH)
      GTY273329Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the e9 cushion cover connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      e3-1 (B) - e9-2 (B) Always Below 1 Ω
      e3-1 (B) - Body ground Always 10 kΩ or higher
      e3-5 (E) - e9-4 (E) Always Below 1 Ω
      e3-5 (E) - Body ground Always 10 kΩ or higher
      e3-1 (B) - e3-5 (E) Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. CHECK SEAT CLIMATE CONTROL ECU (OPERATION) 
    1. Replace the seat climate control ECU with a new one or normally operating one, and check if a DTC is output.

      OK

      DTC is not output

    NG → See step   15 

    OK → See step   7 

  7. REPLACE SEAT CLIMATE CONTROL ECU. Refer to  DISASSEMBLY 
  8. CHECK HARNESS AND CONNECTOR (SEAT CLIMATE CONTROL ECU - REAR SEATBACK COVER LH) 
    1. Disconnect the f27 ECU connector.
      Fig 3: Checking Harness And Connector (Seat Climate Control ECU - Rear Seatback Cover LH)
      GTY117218Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the f23 seatback cover connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      f27-1 (B) - f23-1 (B) Always Below 1 Ω
      f27-1 (B) - Body ground Always 10 kΩ or higher
      f27-5 (E) - f23-3 (E) Always Below 1 Ω
      f27-5 (E) - Body ground Always 10 kΩ or higher
      f27-1 (B) - f27-5 (E) Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  9. CHECK SEAT CLIMATE CONTROL ECU (OPERATION) 
    1. Replace the seat climate control ECU with a new one or normally operating one, and check if a DTC is output.

      OK

      DTC is not output

    NG → See step   16 

    OK → See step   10 

  10. REPLACE SEAT CLIMATE CONTROL ECU. Refer to  DISASSEMBLY 
  11. CHECK HARNESS AND CONNECTOR (SEAT CLIMATE CONTROL ECU - REAR SEATBACK COVER RH) 
    1. Disconnect the f7 ECU connector.
      Fig 4: Checking Harness And Connector (Seat Climate Control ECU - Rear Seatback Cover RH)
      GTY117219Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the f3 seatback cover connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      f7-1 (B) - f3-1 (B) Always Below 1 Ω
      f7-1 (B) - Body ground Always 10 kΩ or higher
      f7-5 (E) - f3-3 (E) Always Below 1 Ω
      f7-5 (E) - Body ground Always 10 kΩ or higher
      f7-1 (B) - f7-5 (E) Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  12. CHECK SEAT CLIMATE CONTROL ECU (OPERATION) 
    1. Replace the seat climate control ECU with a new one or normally operating one, and check if a DTC is output.

      OK

      DTC is not output

      RESULT

      Result Proceed to
      OK (w/o Ottoman) A
      OK (w/ Ottoman) B
      NG (w/o Ottoman) C
      NG (w/ Ottoman) D

    D → See step   19 

    C → See step   17 

    B → See step   18 

    A → See step   13 

  13. REPLACE SEAT CLIMATE CONTROL ECU. Refer to  DISASSEMBLY 
  14. REPLACE FRONT SEAT CUSHION COVER LH. Refer to  DISASSEMBLY 
  15. REPLACE FRONT SEAT CUSHION COVER RH. Refer to  DISASSEMBLY 
  16. REPLACE REAR SEATBACK COVER LH. Refer to  DISASSEMBLY 
  17. REPLACE REAR SEATBACK COVER RH. Refer to  DISASSEMBLY 
  18. REPLACE SEAT CLIMATE CONTROL ECU. Refer to  DISASSEMBLY 
  19. REPLACE REAR SEATBACK COVER RH. Refer to  DISASSEMBLY 
RENDER: 1.0x

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