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Home >> Lexus >> 2013 >> IS 250 Base, RWD >> Repair and Diagnosis >> Body & Frame >> Seats >> Climate Control Seat System (Diagnostics - Introduction) >> 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

    B → See step   10 

    C → See step   18 

    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.
      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.
      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.
      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.
      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.
      GTY259036Courtesy 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 [08/2012 - ] .
      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.
      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.
      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.
      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.
      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.
      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.
      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 [08/2012 - ] .
      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.
      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 [08/2012 - ] .
      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.
      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 [08/2012 - ] - Step 33 
  21. REPLACE SEAT CLIMATE CONTROL BLOWER LH. Refer to  DISASSEMBLY [08/2012 - ] - Step 32 
  22. REPLACE SEAT CLIMATE CONTROL BLOWER LH. Refer to  DISASSEMBLY [08/2012 - ] - Step 33 
  23. REPLACE SEAT HEATER SWITCH. Refer to  REMOVAL [08/2012 - ] 
  24. REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [08/2012 - ] 
  25. REPLACE SEAT BACK CLIMATE CONTROL BLOWER RH. Refer to  DISASSEMBLY [08/2012 - ] - Step 31 
  26. REPLACE SEAT CLIMATE CONTROL BLOWER RH. Refer to  DISASSEMBLY [08/2012 - ] - Step 32 
  27. REPLACE SEAT CLIMATE CONTROL BLOWER RH. Refer to  DISASSEMBLY [08/2012 - ] - Step 32 
  28. REPLACE SEAT HEATER SWITCH. Refer to  REMOVAL [08/2012 - ] 
  29. REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [08/2012 - ] 
  30. REPLACE SEAT HEATER SWITCH. Refer to  REMOVAL [08/2012 - ] 
  31. REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [08/2012 - ]