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Climate Control Seat System does not Operate [11/2017 - ]: Procedure

  1. CHECK DTC OUTPUT 
    1. Clear DTCs.

      Refer to DTC CHECK / CLEAR [09/2014 - ]

      Body Electrical > Air Conditioner > Clear DTCs 

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [09/2014 - ]

      Body Electrical > Air Conditioner > Trouble Codes 

      Result

      Result Proceed to
      DTC B14B5 is not output A
      DTC B14B5 output B

    Result: 

    GO TO SEAT HEATER SYSTEM. Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2014 - ] 

    Result: 

    See step  2

  2. CHECK CLIMATE CONTROL SEAT OPERATION 
    1. Check the climate control seat operation.

      Refer to ON-VEHICLE INSPECTION [09/2014 - ] 

      Result

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

    Result: 

    See step  12

    Result: 

    See step  21

    Result: 

    See step  3

  3. CHECK CLIMATE CONTROL SEAT OPERATION (FRONT LH SEAT) 
    1. Check the climate control seat operation again.

      Refer to ON-VEHICLE INSPECTION [09/2014 - ] 

      Result

      Result Proceed to
      Only seatback climate control blower LH does not operate A
      Only seat cushion climate control blower assembly LH does not operate B
      Both climate control blowers do not operate C

    Result: 

    REPLACE SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY LH. Refer to  DISASSEMBLY [09/2014 - ] 

    Result: 

    See step  7

    Result: 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY LH - SEATBACK CLIMATE CONTROL BLOWER LH) 
    1. Disconnect the d1 seatback climate control blower LH connector.
    2. Disconnect the b12 seat cushion climate control blower assembly LH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      d1-1 (IGB) - b12-3 (IGB) Always Below 1 Ω
      d1-1 (IGB) or b12-3 (IGB) - Body ground Always 10 kΩ or higher
      d1-2 (VS) - b12-4 (VS) Always Below 1 Ω
      d1-2 (VS) or b12-4 (VS) - Body ground Always 10 kΩ or higher
      d1-3 (GND) - b12-2 (GND2) Always Below 1 Ω
      d1-3 (GND) or b12-2 (GND2) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. REPLACE SEATBACK CLIMATE CONTROL BLOWER LH 
    1. Temporarily replace the seatback climate control blower LH with a new or known good one.

      Refer to DISASSEMBLY [09/2014 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  6

  6. CHECK CLIMATE CONTROL SEAT OPERATION 
    1. Check the climate control seat operation.

      Refer to ON-VEHICLE INSPECTION [09/2014 - ] 

      OK

      The climate control seat operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (SEATBACK CLIMATE CONTROL BLOWER LH WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY LH. Refer to  DISASSEMBLY [09/2014 - ] 

  7. CHECK HARNESS AND CONNECTOR (IG POWER SUPPLY - SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY LH - BODY GROUND) 
    1. Disconnect the b12 seat cushion climate control blower assembly LH connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      b12-1 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      b12-1 (IG) - Body ground Engine switch off Below 1 V

      Standard Resistance

      Tester Connection Condition Specified Condition
      b12-6 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY LH - AIR CONDITIONING AMPLIFIER ASSEMBLY) 
    1. Disconnect the O9 air conditioning amplifier assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      b12-5 (SI) - O9-10 (LOUT) Always Below 1 Ω
      b12-5 (SI) or O9-10 (LOUT) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY 
    1. Reconnect the O9 air conditioning amplifier assembly connector.
    2. Reconnect the b12 seat cushion climate control blower assembly LH connector.
      GTY500939Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Air Conditioning Amplifier Assembly)
    3. Check the input signal waveform.
      1. Connect an oscilloscope to terminal O9-10 (LOUT) and body ground with the air conditioning amplifier assembly connector still connected.
      2. Check the signal waveform according to the condition(s) in the table below.
        MEASUREMENT CONDITION

        Item Content
        Tester Connection O9-10 (LOUT) - Body ground
        Tool Setting 1 V/DIV., 1 ms/DIV.
        Vehicle Condition
        • Engine switch on (IG)
        • Refreshing seat switch (for LH) on

          (blower position)

        OK

        Waveform is similar to that shown in the illustration.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY LH. Refer to  DISASSEMBLY [09/2014 - ] 

    Result: 

    NG 

    See step  10

  10. REPLACE REFRESHING SEAT SWITCH 
    1. Temporarily replace the refreshing seat switch with a new or known good one.

      Refer to REMOVAL [09/2014 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  11

  11. CHECK CLIMATE CONTROL SEAT OPERATION 
    1. Check the climate control seat operation.

      Refer to ON-VEHICLE INSPECTION [09/2014 - ] 

      OK

      The climate control seat operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (REFRESHING SEAT SWITCH WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [09/2014 - ] 

  12. CHECK CLIMATE CONTROL SEAT OPERATION (FRONT RH SEAT) 
    1. Check the climate control seat operation again.

      Refer to ON-VEHICLE INSPECTION [09/2014 - ] 

      Result

      Result Proceed to
      Only seatback climate control blower RH does not operate A
      Only seat cushion climate control blower assembly RH does not operate B
      Both climate control blowers do not operate C

    Result: 

    REPLACE SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY RH. Refer to  DISASSEMBLY [09/2014 - ] 

    Result: 

    See step  16

    Result: 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY RH - SEATBACK CLIMATE CONTROL BLOWER RH) 
    1. Disconnect the c1 seatback climate control blower RH connector.
    2. Disconnect the a13 seat cushion climate control blower assembly RH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      c1-1 (IGB) - a13-3 (IGB) Always Below 1 Ω
      c1-1 (IGB) or a13-3 (IGB) - Body ground Always 10 kΩ or higher
      c1-2 (VS) - a13-4 (VS) Always Below 1 Ω
      c1-2 (VS) or a13-4 (VS) - Body ground Always 10 kΩ or higher
      c1-3 (GND) - a13-2 (GND2) Always Below 1 Ω
      c1-3 (GND) or a13-2 (GND2) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  14

  14. REPLACE SEATBACK CLIMATE CONTROL BLOWER RH 
    1. Temporarily replace the seatback climate control blower RH with a new or known good one.

      Refer to DISASSEMBLY [09/2014 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  15

  15. CHECK CLIMATE CONTROL SEAT OPERATION 
    1. Check the climate control operation again.

      Refer to ON-VEHICLE INSPECTION [09/2014 - ] 

      OK

      The climate control seat operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (SEATBACK CLIMATE CONTROL BLOWER RH WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY RH. Refer to  DISASSEMBLY [09/2014 - ] 

  16. CHECK HARNESS AND CONNECTOR (IG POWER SUPPLY - SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY RH - BODY GROUND) 
    1. Disconnect the a13 seat cushion climate control blower assembly RH connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      a13-1 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      a13-1 (IG) - Body ground Engine switch off Below 1 V

      Standard Resistance

      Tester Connection Condition Specified Condition
      a13-6 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  17

  17. CHECK HARNESS AND CONNECTOR (SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY RH - AIR CONDITIONING AMPLIFIER ASSEMBLY) 
    1. Disconnect the O9 air conditioning amplifier assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      a13-5 (SI) - O9-11 (ROUT) Always Below 1 Ω
      a13-5 (SI) or O9-11 (ROUT) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  18

  18. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY 
    1. Reconnect the O9 air conditioning amplifier assembly connector.
    2. Reconnect the a13 seat cushion climate control blower assembly RH connector.
      GTY518257Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Air Conditioning Amplifier Assembly)
    3. Check the input signal waveform.
      1. Connect an oscilloscope to terminal O9-11 (ROUT) and body ground with the air conditioning amplifier assembly connector still connected.
      2. Check the signal waveform according to the condition(s) in the table below.
        MEASUREMENT CONDITION

        Item Content
        Tester Connection O9-11 (ROUT) - Body ground
        Tool Setting 1 V/DIV., 1 ms/DIV.
        Vehicle Condition
        • Engine switch on (IG)
        • Refreshing seat switch (for RH) on

          (blower position)

        OK

        Waveform is similar to that shown in the illustration.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE SEAT CUSHION CLIMATE CONTROL BLOWER ASSEMBLY RH. Refer to  DISASSEMBLY [09/2014 - ] 

    Result: 

    NG 

    See step  19

  19. REPLACE REFRESHING SEAT SWITCH 
    1. Temporarily replace the refreshing seat switch with a new or known good one.

      Refer to REMOVAL [09/2014 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  20

  20. CHECK CLIMATE CONTROL SEAT OPERATION 
    1. Check the climate control seat operation.

      Refer to ON-VEHICLE INSPECTION [09/2014 - ] 

      OK

      The climate control seat operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (REFRESHING SEAT SWITCH WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [09/2014 - ] 

  21. CHECK HARNESS AND CONNECTOR (IG POWER SUPPLY - REFRESHING SEAT SWITCH - BODY GROUND) 
    1. Disconnect the O94 refreshing seat switch connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      O94-1 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      O94-1 (IG) - Body ground Engine switch off Below 1 V

      Standard Resistance

      Tester Connection Condition Specified Condition
      O94-4 (E) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  22

  22. REPLACE REFRESHING SEAT SWITCH 
    1. Temporarily replace the refreshing seat switch with a new or known good one.

      Refer to REMOVAL [09/2014 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  23

  23. CHECK CLIMATE CONTROL SEAT OPERATION 
    1. Check the climate control seat operation.

      Refer to ON-VEHICLE INSPECTION [09/2014 - ] 

      OK

      The climate control seat operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (REFRESHING SEAT SWITCH WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY. Refer to  REMOVAL [09/2014 - ]