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Home >> Lexus >> 2009 >> IS F >> Repair and Diagnosis >> Body & Frame >> Seats >> Climate Control Seat System (Diagnostics) >> Climate Control Seat System >> Climate Control Seat System does not Operate >> Procedure
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Climate Control Seat System does not Operate: Procedure

  1. SYSTEM CHECK 
    1. Check the climate control seat operation.

      Result

      Result Proceed to
      Climate control seat does not operate (Front LH) A
      Climate control seat does not operate (Front RH) B
      Both climate control seats do not operate C

    C → See step   18 

    B → See step   10 

    A: Go to next step 

  2. SYSTEM CHECK 
    1. Check the climate control operation again.

      Result

      Result Proceed to
      Only seat back climate control blower LH does not operate A
      Both climate control blower do not operate B

    B → See step   5 

    A: Go to next step 

  3. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the U13 connector.
      Fig 1: Measuring U13 Connector Voltage
      GTY136053Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      U13-2 (IG) - U13-1 (GND) Engine switch on (IG)
      Blower switch ON (Vol: 1 to 3)      		 6.7 to 9.3 V

    NG → See step   4 

    OK → See step   20 

  4. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the U12 connector.
      Fig 2: Measuring U12 Connector Resistance
      GTY132682Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U13-2 (IG) - U12-2 (CTB) Always Below 1 Ω
      U13-2 (IG) - Body ground Always 10 kΩ or higher
      U13-1 (GND) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   21 

  5. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the U12 connector.
      Fig 3: Measuring U12 Connector Resistance
      GTY127442Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage and Resistance

      Tester Connection Condition Specified Condition
      U12-1 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      U12-4 (GND) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY 
    1. Reconnect the U12 connector.
      Fig 4: Measuring U12 Connector Resistance
      GTY143916Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the input signal waveform.
      1. Connect the oscilloscope to terminal 3 and body ground with the climate control blower LH connector still connected.
      2. Check the signal waveform according to the condition(s) in the table below.
        Terminal No. U12-3 (SIGN) - Body ground
        Tool Setting 2 V/DIV., 500 μsec./DIV.
        Vehicle Condition Engine switch on (IG), seat hater switch ON

    NG → See step   7 

    OK → See step   22 

  7. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the U12 and J59 connectors.
      Fig 5: Measuring U12 & J59 Connector Resistance
      GTY124890Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U12-3 (SIGN) - J59-16 (LOUT) Always Below 1 Ω
      U12-3 (SIGN) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. INSPECT SEAT HEATER SWITCH 
    1. Remove the seat heater switch. Refer to REMOVAL .
      Fig 6: Measuring J45 Connector Resistance
      GTY126636Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      J45-8 (SVS5) - J45-10 (SVSG) Always 0.77 to 1.43 kΩ
      J45-7 (BLLH) - J45-10 (SVSG) Blower switch OFF 0.77 to 1.43 kΩ
      J45-7 (BLLH) - J45-10 (SVSG) Blower switch ON (Vol: 3) 110 to 270 Ω

    NG → See step   23 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR 
    1. Measure the resistance according to the value(s) in the table below.
      Fig 7: Measuring J45 & J59 Connectors
      GTY136697Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      J45-7 (BLLH) - J59-2 (SW 5) Always Below 1 Ω
      J45-8 (SVS5) - J59-7 (S5-4) Always Below 1 Ω
      J45-10 (SVSG) - J59-10 (SG-4) Always Below 1 Ω
      J45-12 (E) - Body ground Always Below 1 Ω
      J45-7 (BLLH) - Body ground Always 10 kΩ or higher
      J45-8 (SVS5) - Body ground Always 10 kΩ or higher
      J45-10 (SVSG) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   24 

  10. SYSTEM CHECK 
    1. Check the climate control operation again.

      Result

      Result Proceed to
      Only seat back climate control blower RH does not operate A
      Both climate control blower do not operate B

    B → See step   13 

    A: Go to next step 

  11. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the T13 connector.
    2. Measure the voltage according to the value(s) in the table below.
      Fig 8: Measuring T13 Connector
      GTY136049Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      T13-2 (IG) - T13-1 (GND) Engine switch on (IG)
      Blower switch ON (Vol: 1 to 3)      		 6.7 to 9.3 V

    NG → See step   12 

    OK → See step   25 

  12. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the T12 connector.
      Fig 9: Measuring T12 Connector
      GTY132686Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      T13-2 (IG) - T12-2 (CTB) Always Below 1 Ω
      T13-2 (IG) - Body ground Always 10 kΩ or higher
      T13-1 (GND) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   26 

  13. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the T12 connector.
      Fig 10: Measuring T12 Connector
      GTY127438Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage and Resistance

      Tester Connection Condition Specified Condition
      T12-1 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      T12-4 (GND) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  14. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY 
    1. Reconnect the T12 connector.
      Fig 11: Measuring T12 Connector
      GTY143919Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the input signal waveform.
      1. Connect the oscilloscope to terminal 3 and body ground with the climate control blower RH connector still connected.
      2. Check the signal waveform according to the condition(s) in the table below.
        Terminal No. T12-3 (SIGN) - Body ground
        Tool Setting 2 V/DIV., 500 μsec./DIV.
        Vehicle Condition Engine switch on (IG), seat hater switch ON

    NG → See step   15 

    OK → See step   27 

  15. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the T12 and J59 connectors.
      Fig 12: Measuring T12 & J59 Connector
      GTY124888Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      T12-3 (SIGN) - J59-8 (ROUT) Always Below 1 Ω
      T12-3 (SIGN) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  16. INSPECT SEAT HEATER SWITCH 
    1. Remove the seat heater switch. Refer to REMOVAL .
      Fig 13: Measuring J45-8 (SVS5) - J45-10 (SVSG)
      GTY142046Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      J45-8 (SVS5) - J45-10 (SVSG) Always 0.77 to 1.43 kΩ
      J45-9 (BLRH) - J45-10 (SVSG) Blower switch OFF 0.77 to 1.43 kΩ
      J45-9 (BLRH) - J45-10 (SVSG) Blower switch ON (Vol: 3) 110 to 270 Ω

    NG → See step   28 

    OK: Go to next step 

  17. CHECK HARNESS AND CONNECTOR 
    1. Measure the resistance according to the value(s) in the table below.
      Fig 14: Measuring J45-9 (BLRH) - J59-3 (SW 4)
      GTY136700Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      J45-9 (BLRH) - J59-3 (SW 4) Always Below 1 Ω
      J45-8 (SVS5) - J59-7 (S5-4) Always Below 1 Ω
      J45-10 (SVSG) - J59-10 (SG-4) Always Below 1 Ω
      J45-12 (E) - Body ground Always Below 1 Ω
      J45-9 (BLRH) - Body ground Always 10 kΩ or higher
      J45-8 (SVS5) - Body ground Always 10 kΩ or higher
      J45-10 (SVSG) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   29 

  18. INSPECT SEAT HEATER SWITCH 
    1. Remove the seat heater switch. Refer to REMOVAL .
      Fig 15: Measuring J45-8 (SVS5) - J45-10 (SVSG)
      GTY126638Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      J45-8 (SVS5) - J45-10 (SVSG) Always 0.77 to 1.43 kΩ
      J45-9 (BLRH) - J45-10 (SVSG) Blower switch OFF 0.77 to 1.43 kΩ
      J45-9 (BLRH) - J45-10 (SVSG) Blower switch ON (Vol: 3) 110 to 270 Ω
      J45-7 (BLLH) - J45-10 (SVSG) Blower switch OFF 0.77 to 1.43 kΩ
      J45-7 (BLLH) - J45-10 (SVSG) Blower switch ON (Vol. 3) 110 to 270 Ω

    NG → See step   30 

    OK: Go to next step 

  19. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the J59 connector.
      Fig 16: Measuring J45-8 (SVS5) - J59-7 (S5-4)
      GTY136701Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      J45-8 (SVS5) - J59-7 (S5-4) Always Below 1 Ω
      J45-10 (SVSG) - J59-10 (SG-4) Always Below 1 Ω
      J45-8 (SVS5) - Body ground Always 10 kΩ or higher
      J45-10 (SVSG) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   31 

  20. REPLACE SEAT BACK CLIMATE CONTROL BLOWER LH. Refer to  DISASSEMBLY - Step 30 
  21. REPLACE SEAT CLIMATE CONTROL BLOWER LH. Refer to  DISASSEMBLY - Step 32 
  22. REPLACE SEAT CLIMATE CONTROL BLOWER LH. Refer to  DISASSEMBLY - Step 32 
  23. REPLACE SEAT HEATER SWITCH. Refer to  REMOVAL 
  24. REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL 
  25. REPLACE SEAT BACK CLIMATE CONTROL BLOWER RH. Refer to  DISASSEMBLY - Step 30 
  26. REPLACE SEAT CLIMATE CONTROL BLOWER RH. Refer to  DISASSEMBLY - Step 32 
  27. REPLACE SEAT CLIMATE CONTROL BLOWER RH. Refer to  DISASSEMBLY - Step 32 
  28. REPLACE SEAT HEATER SWITCH. Refer to  REMOVAL 
  29. REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL 
  30. REPLACE SEAT HEATER SWITCH. Refer to  REMOVAL 
  31. REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL 
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