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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 b14 connector.
      Fig 1: Identifying B14 Connector
      GTY104411Courtesy 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
      b14-2 (IG) - b14-1 (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 b11 connector.
      Fig 2: Identifying B11 & B14 Connectors
      GTY104172Courtesy 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
      b14-2 (IG) - b11-2 (CTB) Always Below 1 Ω
      b14-2 (IG) - Body ground Always Below 1 Ω
      b14-1 (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 b11 connector.
      Fig 3: Identifying B11 Connector
      GTY101758Courtesy 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
      b11-1 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      b11-4 (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 b11 connector.
      Fig 4: Identifying B11 Connector
      GTY102104Courtesy 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. b11-3 (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 b11 and K51 connectors.
      Fig 5: Identifying B11 & K51 Connectors
      GTY101921Courtesy 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
      b11-3 (SIGN) - J59-16 (LOUT) Always Below 1 Ω
      b11-3 (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.
      Fig 6: Identifying Seat Heater Switch Connector
      GTY100569Courtesy 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
      K40-8 (SVS5) - K40-10 (SVSG) Always Below 1 kΩ or higher
      K40-7 (BLLH) - K40-10 (SVSG) Blower switch OFF Below 1.1 kΩ
      K40-7 (BLLH) - K40-10 (SVSG) Blower switch ON (Vol: 3) Below 111 Ω

    NG → REPLACE SEAT HEATER SWITCH 

    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: Identifying K40 & K51 Connector
      GTY100598Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      K40-7(BLLH) - K51-2 (SW 5) Always Below 1 Ω
      K40-8 (SVS5) - K51-7 (S5-4) Always Below 1 Ω
      K40-10 (SVSG) - K51-10 (SG-4) Always Below 1 Ω
      K40-12 (E) - Body ground Always Below 1 Ω
      K40-7 (BLLH) - Body ground Always 10 kΩ or higher
      K40-8 (SVS5) - Body ground Always 10 kΩ or higher
      K40-10 (SVSG) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   23 

  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 a14 connector.
    2. Measure the voltage according to the value(s) in the table below.
      Fig 8: Identifying A14 Connector
      GTY103430Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      a14-2 (IG) - a14-1 (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   24 

  12. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the a11 connector.
      Fig 9: Identifying A11 & A14 Connector
      GTY102246Courtesy 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
      a14-2 (IG) - a11-2 (CTB) Always Below 1 Ω
      a14-2 (IG) - Body ground Always Below 1 Ω
      a14-1 (GND) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   25 

  13. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the a11 connector.
      Fig 10: Identifying A11 Connector
      GTY101757Courtesy 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
      a11-1 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      a11-4 (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 a11 connector.
      Fig 11: Identifying A11 Connector
      GTY102105Courtesy 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. a11-3 (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   26 

  15. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the a11 and K51 connectors.
      Fig 12: Identifying A11 & K51 Connectors
      GTY101920Courtesy 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
      a11-3 (SIGN) - J59-8 (ROUT) Always Below 1 Ω
      a11-3 (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.
      Fig 13: Identifying Seat Heater Switch Connector
      GTY100568Courtesy 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
      K40-8 (SVS5) - K40-10 (SVSG) Always Below 1 kΩ
      K40-9 (BLRH) - K40-10 (SVSG) Blower switch OFF Below 1.1 kΩ
      K40-9 (BLRH) - K40-10 (SVSG) Blower switch ON (Vol: 3) Below 111 Ω

    NG → REPLACE SEAT HEATER SWITCH 

    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: Identifying K40 & K51 Connectors
      GTY100601Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      K40-9(BLRH) - K51-3 (SW 4) Always Below 1 Ω
      K40-8 (SVS5) - K51-7 (S5-4) Always Below 1 Ω
      K40-10 (SVSG) - K51-10 (SG-4) Always Below 1 Ω
      K40-12 (E) - Body ground Always Below 1 Ω
      K40-9 (BLRH) - Body ground Always 10 kΩ or higher
      K40-8 (SVS5) - Body ground Always 10 kΩ or higher
      K40-10 (SVSG) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   27 

  18. INSPECT SEAT HEATER SWITCH 
    1. Remove the seat heater switch.
      Fig 15: Identifying Seat Heater Switch Connector
      GTY103819Courtesy 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
      K40-8 (SVS5) - K40-10 (SVSG) Always Below 1 kΩ
      K40-9 (BLRH) - K40-10 (SVSG) Blower switch OFF Below 1.1 kΩ
      K40-9 (BLRH) - K40-10 (SVSG) Blower switch ON (Vol: 3) Below 111 Ω
      K40-8 (SVS5) - K40-10 (SVSG) Always Below 1 kΩ
      K40-7 (BLLH) - K40-10 (SVSG) Blower switch OFF Below 1.1 kΩ
      K40-7 (BLLH) - K40-10 (SVSG) Blower switch ON (Vol. 3) Below 111 Ω

    NG → REPLACE SEAT HEATER SWITCH 

    OK: Go to next step 

  19. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the K51 connector.
      Fig 16: Identifying K40 & K51
      GTY100603Courtesy 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
      K40-8 (SVS5) - K51-7 (S5-4) Always Below 1 Ω
      K40-10 (SVSG) - K51-10 (SG-4) Always Below 1 Ω
      K40-8 (SVS5) - Body ground Always 10 kΩ or higher
      K40-10 (SVSG) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   28 

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