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Inspection Procedure

  1. SYSTEM CHECK 
    1. Check if the climate control seat system operates normally.

      Result 

      RESULT CHART

      Result Proceed to
      Climate control does not operate on driver side A
      Climate control does not operate on front passenger side B
      Climate control does not operate on both driver and front passenger sides C

    B: Go to step  8

    C: Go to step  14

    A: Go to next step. 

  2. CHECK WIRE HARNESS 
    1. Disconnect the U15 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      U15-4 (GND) - Body ground Always Below 1 Ω

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      U15-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 1: Identifying U15 Connector Terminals
      G05253937Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reconnect the U15 connector.
    4. Disconnect the U14 connector.
    5. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      U14-1 (GND) - Body ground Always Below 1 Ω

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      U14-2 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 2: Identifying U14 Connector Terminals
      G05253938Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    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 an oscilloscope to terminal U15-3 (SIGN) 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.
        WAVEFORM REFERENCE

        Item Condition
        Tool setting 2 V/DIV., 500 μsec/DIV.
        Vehicle condition Engine switch on (IG), seat heater switch ON

        OK: The waveform is displayed as shown in the illustration. 

        Result 

        RESULT CHART

        Result Proceed to
        NG A
        OK (Seat cushion blower side) B
        OK (Seatback blower side) C
    Fig 3: Identifying Signal Waveform
    G05253939Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    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 E2 and U15 connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      E2-9 (SVDB) - U15-3 (SIGN) Always Below 1 Ω
      E2-9 (SVDB) - Body ground Always 10 kΩ or higher
    Fig 4: Checking Wire Harness (A/C Amplifier Assembly - Seat Climate Control Blower)
    G05253940Courtesy 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 F3 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-12 (E) - Body ground Always Below 1 Ω

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-5 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 5: Identifying F3 Connector Terminals
      G05253941Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step. 

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

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-7 (BLLH) - F3-10 (SVSG) Blower switch OFF Below 1.1 kΩ
      Blower switch ON (Vol: 3) Below 111 Ω
      F3-8 (SVS5) - F3-10 (SVSG) Always Below 1 kΩ
    Fig 6: Inspecting Seat Heater Switch
    G05253942Courtesy 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. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-7 (BLLH) - E2-15 (SVDS) Always Below 1 Ω
      F3-8 (SVS5) - E2-6 (SG-5) Always Below 1 Ω
      F3-10 (SVSG) - E2-8 (S5-2) Always Below 1 Ω
      F3-12 (E) - Body ground Always Below 1 Ω
      F3-7 (BLLH) - Body ground Always 10 kΩ or higher
      F3-8 (SVS5) - Body ground Always 10 kΩ or higher
      F3-10 (SVSG) - Body ground Always 10 kΩ or higher
    Fig 7: Checking Wire Harness (Seat Heater Switch - A/C Amplifier Assembly)
    G05253943Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: REPLACE A/C AMPLIFIER ASSEMBLY 

  8. CHECK WIRE HARNESS 
    1. Disconnect the T17 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      T17-4 (GND) - Body ground Always Below 1 Ω

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      T17-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V
    3. Reconnect the T17 connector.
      Fig 8: Identifying T17 Connector Terminals
      G05253944Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Disconnect the T16 connector.
    5. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      T16-1 (GND) - Body ground Always Below 1 Ω

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      T16-2 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 9: Identifying T16 Connector Terminals
      G05253945Courtesy 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 an oscilloscope to terminal T17-3 (SIGN) 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.
        WAVEFORM REFERENCE

        Item Condition
        Tool setting 2 V/DIV., 500 μsec/DIV.
        Vehicle condition Engine switch on (IG), seat heater switch ON

        OK: The waveform is displayed as shown in the illustration. 

        Result 

        RESULT CHART

        Result Proceed to
        NG A
        OK (Seat cushion blower side) B
        OK (Seatback blower side) C
    Fig 10: Identifying Signal Waveform
    G05253946Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    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 E2 and T17 connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      E2-10 (SVPB) - T17-3 (SIGN) Always Below 1 Ω
      E2-10 (SVPB) - Body ground Always 10 kΩ or higher
    Fig 11: Checking Wire Harness (A/C Amplifier Assembly - Seat Climate Control Blower)
    G05253947Courtesy 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 F3 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-12 (E) - Body ground Always Below 1 Ω

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-5 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 12: Identifying F3 Connector Terminals
      G05253941Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step. 

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

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-8 (SVS5) - F3-9 (BLRH) Blower switch OFF Below 1.1 kΩ
      Blower switch ON (Vol: 3) Below 111 Ω
      F3-8 (SVS5) - F3-10 (SVSG) Always Below 1 kΩ
    Fig 13: Inspecting Seat Heater Switch
    G05253949Courtesy 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. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-8 (SVS5) - E2-6 (SG-5) Always Below 1 Ω
      F3-9 (BLRH) - E2-16 (SVPS) Always Below 1 Ω
      F3-10 (SVSG) - E2-8 (S5-2) Always Below 1 Ω
      F3-12 (E) - Body ground Always Below 1 Ω
      F3-8 (SVS5) - Body ground Always 10 kΩ or higher
      F3-9 (BLRH) - Body ground Always 10 kΩ or higher
      F3-10 (SVSG) - Body ground Always 10 kΩ or higher
    Fig 14: Checking Wire Harness (Seat Heater Switch - A/C Amplifier Assembly)
    G05253950Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: REPLACE A/C AMPLIFIER ASSEMBLY 

  14. CHECK WIRE HARNESS 
    1. Disconnect the U15 and T17 connectors.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance: Front LH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      U15-4 (GND) - Body ground Always Below 1 Ω
      Fig 15: Identifying U15 And T17 Connector Terminals
      G05253951Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Front RH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      T17-4 (GND) - Body ground Always Below 1 Ω

      Standard voltage: Front LH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      U15-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V

      Front RH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      T17-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V
    3. Reconnect the U15 and T17 connectors.
    4. Disconnect the U14 and T16 connectors.
    5. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance: Front LH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      U14-1 (GND) - Body ground Always Below 1 Ω
      Fig 16: Identifying U14 And T16 Connector Terminals
      G05253952Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Front RH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      T16-1 (GND) - Body ground Always Below 1 Ω

      Standard voltage: Front LH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      U14-2 (IG) - Body ground Engine switch on (IG) 10 to 14 V

      Front RH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      U16-2 (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 an 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.
        WAVEFORM REFERENCE

        Item Condition
        Tool setting 2 V/DIV., 500 μsec/DIV.
        Vehicle condition Engine switch on (IG), seat heater switch ON

        OK: The waveform is displayed as shown in the illustration. 

        Result 

        RESULT CHART

        Result Proceed to
        NG A
        OK (Seat cushion blower side) B
        OK (Seatback blower side) C
    Fig 17: Identifying Signal Waveform
    G05253953Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    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 E2, U15 and T17 connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance: Front LH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      E2-9 (SVDB) - U15-3 (SIGN) Always Below 1 Ω
      E2-9 (SVDB) - Body ground Always 10 kΩ or higher

      Front RH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      E2-10 (SVPB) - T17-3 (SIGN) Always Below 1 Ω
      E2-10 (SVPB) - Body ground Always 10 kΩ or higher
    Fig 18: Checking Wire Harness (A/C Amplifier Assembly - Seat Climate Control Blower)
    G05253954Courtesy 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 F3 connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-12 (E) - Body ground Always Below 1 Ω

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-5 (IG) - Body ground Engine switch on (IG) 10 to 14 V
    Fig 19: Identifying F3 Connector Terminals
    G05253941Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step. 

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

      Standard resistance: Front LH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-7 (BLLH) - F3-10 (SVSG) Blower switch OFF Below 1.1 kΩ
      Blower switch ON (Vol: 3) Below 111 Ω
      F3-8 (SVS5) - F3-10 (SVSG) Always Below 1 kΩ

      Front RH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-8 (SVS5) - F3-9 (BLRH) Blower switch OFF Below 1.1 kΩ
      Blower switch ON (Vol: 3) Below 111 Ω
      F3-8 (SVS5) - F3-10 (SVSG) Always Below 1 kΩ
    Fig 20: Inspecting Seat Heater Switch
    G05253956Courtesy 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. Measure the resistance according to the value(s) in the table below.

      Standard resistance: Front LH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-7 (BLLH) - E2-15 (SVDS) Always Below 1 Ω
      F3-8 (SVS5) - E2-8 (S5-2) Always Below 1 Ω
      F3-10 (SVSG) - E2-6 (SG-5) Always Below 1 Ω
      F3-12 (E) - Body ground Always Below 1 Ω
      F3-7 (BLLH) - Body ground Always 10 kΩ or higher
      F3-8 (SVS5) - Body ground Always 10 kΩ or higher
      F3-10 (SVSG) - Body ground Always 10 kΩ or higher
      Fig 21: Checking Wire Harness (Seat Heater Switch - A/C Amplifier Assembly)
      G05253957Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Front RH 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F3-8 (SVS5) - E2-8 (S5-2) Always Below 1 Ω
      F3-9 (BLRH) - E2-16 (SVPS) Always Below 1 Ω
      F3-10 (SVSG) - E2-6 (SG-5) Always Below 1 Ω
      F3-12 (E) - Body ground Always Below 1 Ω
      F3-8 (SVS5) - Body ground Always 10 kΩ or higher
      F3-9 (BLRH) - Body ground Always 10 kΩ or higher
      F3-10 (SVSG) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE WIRE HARNESS 

    OK: REPLACE A/C AMPLIFIER ASSEMBLY 

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