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Inspection Procedure

  1. SYSTEM CHECK 
    SYSTEM CHECK

    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: Go to step  8

    C: Go to step  14

    A: Go to next step 

  2. CHECK WIRE HARNESS 
    1. Disconnect the U12 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS RESISTANCE

      Tester Connection Condition Specified Condition
      U12-4 (GND) - Body ground Always Below 1 Ω
      Fig 1: Identifying U12 Connector Terminals
      G05320900Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Voltage 

      WIRE HARNESS VOLTAGE

      Tester Connection Condition Specified Condition
      U12-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V
    3. Reconnect the U12 connector.
    4. Disconnect the U13 connector.
    5. Measure the voltage and resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS RESISTANCE

      Tester Connection Condition Specified Condition
      U13-1 (GND) - Body ground Always Below 1 Ω
      Fig 2: Identifying U13 Connector Terminals
      G05320901Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Voltage 

      WIRE HARNESS VOLTAGE

      Tester Connection Condition Specified Condition
      U13-2 (IG) - Body ground Engine switch on (IG) 10 to 14 V

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  3. INSPECT SEAT CLIMATE CONTROL BLOWER 
    1. Check the input signal waveform.
      1. Connect the oscilloscope to terminal 3 and body ground with the climate control blower connector still connected.
      2. Check the signal waveform according to the condition(s) in the table below.
        SEAT CLIMATE CONTROL BLOWER

        Item Condition
        Tool setting 2 V/DIV., 500 μsec/DIV.,
        Vehicle condition Engine switch on (IG), seat heater switch ON
        Fig 3: Identifying Seat Climate Control Blower
        G05320902Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        OK: 

        The waveform is displayed as shown in the illustration. 

        Result 

        RESULT CHART

        NG A
        OK (Seat cushion blower side) B
        OK (Seatback blower side) C

    B: REPLACE SEAT CUSHION BLOWER 

    C: REPLACE SEATBACK BLOWER 

    A: Go to next step 

  4. CHECK WIRE HARNESS (A/C AMPLIFIER ASSEMBLY - SEAT CLIMATE CONTROL BLOWER) 
    1. Disconnect the J59, U12 and U13 connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS (A/C AMPLIFIER ASSEMBLY - SEAT CLIMATE CONTROL BLOWER)

      Tester Connection Condition Specified Condition
      J59-16 (LOUT) - U12-3 (SIGN) Always Below 1 Ω
      J59-16 (LOUT) - U13-3 (FCTB) Always Below 1 Ω
      J59-16 (LOUT) - Body ground Always 10 kΩ or higher
      Fig 4: Identifying Wire Harness (A/C Amplifier Assembly - Seat Climate Control Blower)
      G05320903Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  5. CHECK WIRE HARNESS (SEAT HEATER SWITCH) 
    1. Disconnect the J45 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS (SEAT HEATER SWITCH) RESISTANCE

      Tester Connection Condition Specified Condition
      J45-12 (E) - Body ground Always Below 1 Ω
      Fig 5: Identifying J45 Connector Terminals
      G05320904Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Voltage 

      WIRE HARNESS (SEAT HEATER SWITCH) VOLTAGE

      Tester Connection Condition Specified Condition
      J45-5 (IG) - Body ground Engine switch on (IG) 10 to 14 V

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  6. INSPECT SEAT HEATER SWITCH 
    1. Disconnect the J45 switch.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      SEAT HEATER SWITCH RESISTANCE

      Tester Connection Condition Specified Condition
      J45-8 (ASS5) - J45-10 (SGND) Always Below 1 kΩ
      J45-9 (LH) - J45-10 (SGND) Blower switch OFF Below 1.1 kΩ
      Blower switch ON (Vol: 3) Below 111 Ω
      Fig 6: Identifying Seat Heater Switch
      G05320905Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SEAT HEATER SWITCH 

    OK: Go to next step 

  7. CHECK WIRE HARNESS (SEAT HEATER SWITCH - A/C AMPLIFIER ASSEMBLY) 
    1. Disconnect the J45 and J59 connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS (SEAT HEATER SWITCH - A/C AMPLIFIER ASSEMBLY)

      Tester Connection Condition Specified Condition
      J45-8 (ASS5) - J59-7 (S5-4) Always Below 1 Ω
      J45-9 (LH) - J59-3 (SW-4) Always Below 1 Ω
      J45-10 (SGND) - J59-10 (SG-4) Always Below 1 Ω
      J45-12 (E) - Body ground Always Below 1 Ω
      J45-8 (ASS5) - Body ground Always 10 kΩ or higher
      J45-9 (LH) - Body ground Always 10 kΩ or higher
      Fig 7: Identifying Wire Harness (Seat Heater Switch - A/C Amplifier Assembly)
      G05320906Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: REPLACE A/C AMPLIFIER ASSEMBLY 

  8. CHECK WIRE HARNESS 
    1. Disconnect the T12 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS RESISTANCE

      Tester Connection Condition Specified Condition
      T12-4 (GND) - Body ground Always Below 1 Ω

      Voltage 

      WIRE HARNESS VOLTAGE

      Tester Connection Condition Specified Condition
      T12-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 8: Identifying T12 Connector Terminals
      G05320907Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reconnect the T12 connector.
    4. Disconnect the T13 connector.
    5. Measure the voltage and resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS RESISTANCE

      Tester Connection Condition Specified Condition
      T13-1 (GND) - Body ground Always Below 1 Ω

      Voltage 

      WIRE HARNESS VOLTAGE

      Tester Connection Condition Specified Condition
      T13-2 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 9: Identifying T13 Connector Terminals
      G05320908Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  9. INSPECT SEAT CLIMATE CONTROL BLOWER 
    1. Check the input signal waveform.
      1. Connect the oscilloscope to terminal 3 and body ground with the climate control blower connector still connected.
      2. Check the signal waveform according to the condition(s) in the table below.
        SEAT CLIMATE CONTROL BLOWER

        Item Condition
        Tool setting 2 V/DIV., 500 μsec/DIV.,
        Vehicle condition Engine switch on (IG), seat heater switch ON
        Fig 10: Identifying Seat Climate Control Blower
        G05320909Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        OK: 

        The waveform is displayed as shown in  Fig 10 . 

        Result 

        RESULT CHART

        NG A
        OK (Seat cushion blower side) B
        OK (Seatback blower side) C

    B: REPLACE SEAT CUSHION BLOWER 

    C: REPLACE SEATBACK BLOWER 

    A: Go to next step 

  10. CHECK WIRE HARNESS (A/C AMPLIFIER ASSEMBLY - SEAT CLIMATE CONTROL BLOWER) 
    1. Disconnect the J59, T12 and T13 connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS (A/C AMPLIFIER ASSEMBLY - SEAT CLIMATE CONTROL BLOWER)

      Tester Connection Condition Specified Condition
      J59-8 (ROUT) - T12-3 (SIGN) Always Below 1 Ω
      J59-8 (ROUT) - T13-3 (VSVG) Always Below 1 Ω
      J59-8 (ROUT) - Body ground Always 10 kΩ or higher
      Fig 11: Identifying Wire Harness (A/C Amplifier Assembly - Seat Climate Control Blower)
      G05320910Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  11. CHECK WIRE HARNESS (SEAT HEATER SWITCH) 
    1. Disconnect the J45 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS (SEAT HEATER SWITCH) RESISTANCE

      Tester Connection Condition Specified Condition
      J45-12 (E) - Body ground Always Below 1 Ω

      Voltage 

      WIRE HARNESS (SEAT HEATER SWITCH) VOLTAGE

      Tester Connection Condition Specified Condition
      J45-5 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 12: Identifying J45 Connector Terminals
      G05320904Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  12. INSPECT SEAT HEATER SWITCH 
    1. Disconnect the J45 switch.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      SEAT HEATER SWITCH

      Tester Connection Condition Specified Condition
      J45-8 (ASS5) - J45-10 (SGND) Always Below 1 kΩ
      J45-7 (RH) - J45-10 (SGND) Blower switch OFF Below 1.1 kΩ
      Blower switch ON (Vol: Below 111 Ω
      Fig 13: Identifying Seat Heater Switch
      G05320912Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SEAT HEATER SWITCH 

    OK: Go to next step 

  13. CHECK WIRE HARNESS (SEAT HEATER SWITCH - A/C AMPLIFIER ASSEMBLY) 
    1. Disconnect the J45 and J59 connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS (SEAT HEATER SWITCH - A/C AMPLIFIER ASSEMBLY)

      Tester Connection Condition Specified Condition
      J45-7 (RH) - J59-2 (SW-5) Always Below 1 Ω
      J45-8 (ASS5) - J59-7 (S5-4) Always Below 1 Ω
      J45-10 (SGND) - J59-10 (SG-4) Always Below 1 Ω
      J45-12 (E) - Body ground Always Below 1 Ω
      J45-7 (RH) - J59-2 (SW-5) Always 10 kΩ or higher
      J45-8 (ASS5) - J59-7 (S5-4) Always 10 kΩ or higher
      Fig 14: Identifying Wire Harness (Seat Heater Switch - A/C Amplifier Assembly)
      G05320913Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: REPLACE A/C AMPLIFIER ASSEMBLY 

  14. CHECK WIRE HARNESS 
    1. Disconnect the U12 (T12) connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      *1: Front LH

      *2: Front RH

      Resistance: 

      Front LH 

      WIRE HARNESS RESISTANCE - FRONT LH

      Tester Connection Condition Specified Condition
      U12-4 (GND) - Body ground Always Below 1 Ω
      Fig 15: Identifying U12 (T12) Connector Terminals
      G05320914Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Front RH 

      WIRE HARNESS RESISTANCE - FRONT RH

      Tester Connection Condition Specified Condition
      T12-4 (GND) - Body ground Always Below 1 Ω

      Voltage: 

      Front LH 

      WIRE HARNESS VOLTAGE - FRONT LH

      Tester Connection Condition Specified Condition
      U12-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V

      Front RH 

      WIRE HARNESS VOLTAGE - FRONT RH

      Tester Connection Condition Specified Condition
      T12-4 (GND) - Body ground Always Below 1 Ω
    3. Reconnect the U12 (T12) connector.
    4. Disconnect the U13 (T13) connector.
    5. Measure the voltage and resistance according to the value(s) in the table below.

      *1: Front LH

      *2: Front RH

      Resistance: 

      Front LH 

      WIRE HARNESS RESISTANCE - FRONT LH

      Tester Connection Condition Specified Condition
      U13-1 (GND) - Body ground Always Below 1 Ω
      Fig 16: Identifying U12 (T12) Seatback Blower Connector
      G05320915Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Front RH 

      WIRE HARNESS RESISTANCE - FRONT RH

      Tester Connection Condition Specified Condition
      T13-1 (GND) - Body ground Always Below 1 Ω

      Voltage: 

      Front LH 

      WIRE HARNESS VOLTAGE - FRONT LH

      Tester Connection Condition Specified Condition
      U13-2 (IG) - Body ground Engine switch on (IG) 10 to 14 V

      Front RH 

      WIRE HARNESS VOLTAGE - FRONT RH

      Tester Connection Condition Specified Condition
      U13-2 (IG) - Body ground Engine switch on (IG) 10 to 14 V

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  15. INSPECT SEAT CLIMATE CONTROL BLOWER 
    1. Check the input signal waveform.
      1. Connect the oscilloscope to terminal 3 and body ground with the climate control blower connector still connected.
      2. Check the signal waveform according to the condition(s) in the table below.
        SEAT CLIMATE CONTROL BLOWER

        Item Condition
        Tool setting 2 V/DIV., 500 μsec/DIV.,
        Vehicle condition Engine switch on (IG), seat heater switch ON
        Fig 17: Identifying Seat Climate Control Blower
        G05320916Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        OK: 

        The waveform is displayed as shown in  Fig 17 . 

        *1: Front LH

        *2: Front RH

        Result 

        RESULT CHART

        NG A
        OK (Seat cushion blower side) B
        OK (Seatback blower side) C

    B: REPLACE SEAT CUSHION BLOWER 

    C: REPLACE SEATBACK BLOWER 

    A: Go to next step 

  16. CHECK WIRE HARNESS (A/C AMPLIFIER ASSEMBLY - SEAT CLIMATE CONTROL BLOWER) 
    1. Disconnect the J59, U12 (T12) and U13 (T13) connectors.

      *1: Front LH

      *2: Front RH

    2. Measure the resistance according to the value(s) in the table below.

      Resistance: 

      Front LH 

      WIRE HARNESS (A/C AMPLIFIER ASSEMBLY - SEAT CLIMATE CONTROL BLOWER) - FRONT LH

      Tester Connection Condition Specified Condition
      J59-16 (LOUT) - U12-3 (SIGN) Always Below 1 Ω
      J59-16 (LOUT) - U13-3 (FCTB) Always Below 1 Ω
      J59-16 (LOUT) - Body ground Always 10 kΩ or higher

      Front RH 

      WIRE HARNESS (A/C AMPLIFIER ASSEMBLY - SEAT CLIMATE CONTROL BLOWER) - FRONT RH

      Tester Connection Condition Specified Condition
      J59-8 (ROUT) - T12-3 (SIGN) Always Below 1 Ω
      J59-8 (ROUT) - T13-3 (VSVG) Always Below 1 Ω,
      J59-8 (ROUT) - Body ground Always 10 kΩ or higher
      Fig 18: Identifying Wire Harness (A/C Amplifier Assembly - Seat Climate Control Blower)
      G05320917Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  17. CHECK WIRE HARNESS (SEAT HEATER SWITCH) 
    1. Disconnect the J45 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Resistance 

      WIRE HARNESS (SEAT HEATER SWITCH) RESISTANCE

      Tester Connection Condition Specified Condition
      J45-12 (E) - Body ground Always Below 1 Ω

      Voltage 

      WIRE HARNESS (SEAT HEATER SWITCH) VOLTAGE

      Tester Connection Condition Specified Condition
      J45-5 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 19: Identifying J45 Connector Terminals
      G05320904Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  18. INSPECT SEAT HEATER SWITCH 
    1. Disconnect the J45 switch.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance: 

      Front LH 

      SEAT HEATER SWITCH - FRONT LH

      Tester Connection Condition Specified Condition
      J45-8 (ASS5) - J45-10 (SGND) Always Below 1 kΩ
      J45-9 (LH) - J45-10 (SGND) Blower switch OFF Below 1.1 kΩ
      Blower switch ON (Vol: 3) Below 111 Ω

      Front RH 

      SEAT HEATER SWITCH - FRONT RH

      Tester Connection Condition Specified Condition
      J45-8 (ASS5) - J45-10 (SGND) Always Below 1 kΩ
      J45-7 (RH) - J45-10 (SGND) Blower switch OFF Below 1.1 kΩ
      Blower switch ON (Vol: 3) Below 111 Ω
      Fig 20: Identifying Seat Heater Switch
      G05320919Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SEAT HEATER SWITCH 

    OK: Go to next step 

  19. CHECK WIRE HARNESS (SEAT HEATER SWITCH - A/C AMPLIFIER ASSEMBLY) 
    1. Disconnect the J45 and J59 connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance: 

      Front LH 

      WIRE HARNESS (SEAT HEATER SWITCH - A/C AMPLIFIER ASSEMBLY) - FRONT LH

      Tester Connection Condition Specified Condition
      J45-8 (ASS5) - J59-7 (S5-1) Always Below 1 Ω
      J45-9 (LH) - J59-3 (SW-4) Always Below 1 Ω
      J45-10 (SGND) - J59-10 (SG-4) Always Below 1 Ω
      J45-12 (E) - Body ground Always Below 1 Ω
      J45-8 (ASS5) - Body ground Always 10 kΩ or higher
      J45-9 (LH) - Body ground Always 10 kΩ or higher

      Front RH 

      WIRE HARNESS (SEAT HEATER SWITCH - A/C AMPLIFIER ASSEMBLY) - FRONT RH

      Tester Connection Condition Specified Condition
      J45-7 (RH) - J59-2 (SW-5) Always Below 1 Ω
      J45-8 (ASS5) - J59-7 (S5-4) Always Below 1 Ω
      J45-10 (SGND) - J59-10 (SG-4) Always Below 1 Ω
      J45-12 (E) - Body ground Always Below 1 Ω
      J45-7 (RH) - Body ground Always 10 kΩ or higher
      J45-8 (ASS5) - Body ground Always 10 kΩ or higher
      Fig 21: Identifying Wire Harness (Seat Heater Switch - A/C Amplifier Assembly)
      G05320920Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: REPLACE A/C AMPLIFIER ASSEMBLY 

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