LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2009 >> ES 350 >> Repair and Diagnosis >> Body & Frame >> Seats >> Climate Control Seat System (Inspection) >> Climate Control Seat System >> Climate Control Seat System does not Operate >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Climate Control Seat System does not Operate: Procedure

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

      Result

      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

    C → See step   14 

    B → See step   8 

    A: Go to next step 

  2. CHECK WIRE HARNESS 
    1. Disconnect the U15 connector.
      Fig 1: Identifying U15 Connector Terminals
      GTY119338Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance

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

      Standard voltage

      Tester Connection Condition Specified Condition
      U15-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V
    3. Reconnect the U15 connector.
    4. Disconnect the U14 connector.
      Fig 2: Identifying U14 Connector Terminals
      GTY119336Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance

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

      Standard voltage

      Tester Connection Condition Specified Condition
      U14-2 (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.
      Fig 3: Identifying Signal Waveform
      GTY141245Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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.
        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 Proceed to
      NG A
      OK (Seat cushion blower side) B
      OK (Seatback blower side) C

    C → REPLACE SEATBACK BLOWER 

    B → REPLACE SEAT CUSHION 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.
      Fig 4: Checking Wire Harness (A/C Amplifier Assembly - Seat Climate Control Blower)
      GTY118832Courtesy 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
      E2-9 (SVDB) - U15-3 (SIGN) Always Below 1 Ω
      E2-9 (SVDB) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  5. CHECK WIRE HARNESS (SEAT HEATER SWITCH) 
    1. Disconnect the F3 connector.
      Fig 5: Identifying F3 Connector Terminals
      GTY140331Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance

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

      Standard voltage

      Tester Connection Condition Specified Condition
      F3-5 (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. Measure the resistance according to the value(s) in the table below.
      Fig 6: Inspecting Seat Heater Switch
      GTY136637Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance

      Tester Connection Condition Specified Condition
      F3-7 (BLLH) - F3-10 (SVSG) Blower switch OFF 0.77 to 1.43 kΩ
      Blower switch ON (Vol: 3) 110 to 270 Ω
      F3-8 (SVS5) - F3-10 (SVSG) Always 0.77 to 1.43 kΩ

    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.
      Fig 7: Checking Wire Harness (Seat Heater Switch - A/C Amplifier Assembly)
      GTY118834Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance

      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

    NG → REPAIR OR REPLACE WIRE HARNESS 

    OK → REPLACE A/C AMPLIFIER ASSEMBLY 

  8. CHECK WIRE HARNESS 
    1. Disconnect the T17 connector.
      Fig 8: Identifying T17 Connector Terminals
      GTY119339Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance

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

      Standard voltage

      Tester Connection Condition Specified Condition
      T17-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V
    3. Reconnect the T17 connector.
    4. Disconnect the T16 connector.
      Fig 9: Identifying T16 Connector Terminals
      GTY136059Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance

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

      Standard voltage

      Tester Connection Condition Specified Condition
      T16-2 (IG) - Body ground Engine switch on (IG) 10 to 14 V

    NG → REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  9. INSPECT SEAT CLIMATE CONTROL BLOWER 
    1. Check the input signal waveform.
      Fig 10: Identifying Signal Waveform
      GTY141244Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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.
        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 Proceed to
      NG A
      OK (Seat cushion blower side) B
      OK (Seatback blower side) C

    C → REPLACE SEATBACK BLOWER 

    B → REPLACE SEAT CUSHION 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.
      Fig 11: Checking Wire Harness (A/C Amplifier Assembly - Seat Climate Control Blower)
      GTY118833Courtesy 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
      E2-10 (SVPB) - T17-3 (SIGN) Always Below 1 Ω
      E2-10 (SVPB) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  11. CHECK WIRE HARNESS (SEAT HEATER SWITCH) 
    1. Disconnect the F3 connector.
      Fig 12: Identifying F3 Connector Terminals
      GTY140331Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance

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

      Standard voltage

      Tester Connection Condition Specified Condition
      F3-5 (IG) - Body ground Engine switch on (IG) 10 to 14 V

    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.
      Fig 13: Inspecting Seat Heater Switch
      GTY136642Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance

      Tester Connection Condition Specified Condition
      F3-10 (SVSG) - F3-9 (BLRH) Blower switch OFF 0.77 to 1.43 kΩ
      Blower switch ON (Vol: 3) 110 to 270 Ω
      F3-8 (SVS5) - F3-10 (SVSG) Always 0.77 to 1.43 kΩ

    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.
      Fig 14: Checking Wire Harness (Seat Heater Switch - A/C Amplifier Assembly)
      GTY122897Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance

      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 

  14. CHECK WIRE HARNESS 
    1. Disconnect the U15 and T17 connectors.
      Fig 15: Identifying U15 And T17 Connector Terminals
      GTY123736Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance

      Front LH 

      Front RH 

      Tester Connection Condition Specified Condition
      U15-4 (GND) - Body ground Always Below 1 Ω
      Tester Connection Condition Specified Condition
      T17-4 (GND) - Body ground Always Below 1 Ω

      Standard voltage

      Front LH 

      Front RH 

      Tester Connection Condition Specified Condition
      U15-1 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      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.
      Fig 16: Identifying U14 And T16 Connector Terminals
      GTY119337Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance

      Front LH 

      Front RH 

      Tester Connection Condition Specified Condition
      U14-1 (GND) - Body ground Always Below 1 Ω
      Tester Connection Condition Specified Condition
      T16-1 (GND) - Body ground Always Below 1 Ω

      Standard voltage

      Front LH 

      Front RH 

      Tester Connection Condition Specified Condition
      U14-2 (IG) - Body ground Engine switch on (IG) 10 to 14 V
      Tester Connection Condition Specified Condition
      T16-2 (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.
      Fig 17: Identifying Signal Waveform
      GTY118831Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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.
        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 Proceed to
      NG A
      OK (Seat cushion blower side) B
      OK (Seatback blower side) C

    C → REPLACE SEATBACK BLOWER 

    B → REPLACE SEAT CUSHION 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.
      Fig 18: Checking Wire Harness (A/C Amplifier Assembly - Seat Climate Control Blower)
      GTY133910Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Front LH 

      Front RH 

      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
      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

    NG → REPAIR OR REPLACE WIRE HARNESS 

    OK: Go to next step 

  17. CHECK WIRE HARNESS (SEAT HEATER SWITCH) 
    1. Disconnect the F3 connector.
      Fig 19: Identifying F3 Connector Terminals
      GTY140331Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard resistance

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

      Standard voltage

      Tester Connection Condition Specified Condition
      F3-5 (IG) - Body ground Engine switch on (IG) 10 to 14 V

    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.
      Fig 20: Inspecting Seat Heater Switch
      GTY119475Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance

      Front LH 

      Front RH 

      Tester Connection Condition Specified Condition
      F3-7 (BLLH) - F3-10 (SVSG) Blower switch OFF 0.77 to 1.43 kΩ
      Blower switch ON (Vol: 3) 110 to 270 Ω
      F3-8 (SVS5) - F3-10 (SVSG) Always 0.77 to 1.43 kΩ
      Tester Connection Condition Specified Condition
      F3-10 (SVSG) - F3-9 (BLRH) Blower switch OFF 0.77 to 1.43 kΩ
      Blower switch ON (Vol: 3) 110 to 270 Ω
      F3-8 (SVS5) - F3-10 (SVSG) Always 0.77 to 1.43 kΩ

    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.
      Fig 21: Checking Wire Harness (Seat Heater Switch - A/C Amplifier Assembly)
      GTY118835Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance

      Front LH 

      Front RH 

      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
      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 

scientia non olet · About LEMON Manuals