AIR CONDITIONING SYSTEM (for Automatic Air Conditioning System) TERMINALS OF ECU


  1. CHECK AIR CONDITIONING AMPLIFIER

    A0117CEE11

    Tech Tips

    Check from the rear of the connector while it is connected to the air conditioning amplifier.

    Standard
    Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
    D15-1 (IG+) - D15-14 (GND) Y - W-B Ignition power supply Ignition switch ON 11 to 14 V
    Ignition switch off Below 1 V
    D15-2 (SOL+) - D15-14 (GND) R - W-B A/C compressor operation signal

    Engine idling

    Blower switch: Lo

    A/C switch: on

    Pulse generation

    (see waveform 1)
    D15-3 (PTC1)* - Body ground G - Body ground PTC heater relay operation signal

    Engine idling

    Set temperature: MAX HOT

    Engine coolant temperature: Below 65°C (149°F)

    Ambient temperature: Below 10°C (50°F)

    Blower switch: off → Lo

    		 Below 1 V → 11 to 14 V
    D15-4 (PTC3)* - Body ground L - Body ground PTC heater relay operation signal

    Engine idling

    Set temperature: MAX HOT

    Engine coolant temperature: Below 65°C (149°F)

    Ambient temperature: Below 10°C (50°F)

    Blower switch: off → Lo

    		 Below 1 V → 11 to 14 V
    D15-9 (PRE) - D15-13 (SG-2) P - GR Air conditioner pressure sensor signal Refrigerant pressure: normal 0.70 to 4.69 V
    D15-9 (PRE) - D15-13 (SG-2) P - GR Air conditioner pressure sensor signal

    Refrigerant pressure: Abnormal (less than 0.176 MPa [1.8 kgf/cm2]) or more than 3.025 MPa [30.9 kgf/cm2])

    		 Below 0.70 V or 4.69 V or more
    D15-10 (S5-3) - D15-14 (GND) L - W-B Power supply for pressure sensor and flow sensor Ignition switch ON 4.75 to 5.25 V
    D15-11 (TX+) - D15-14 (GND) LG - W-B Hi-level CAN bus line Ignition switch ON

    Pulse generation

    (see waveform 3)
    D15-12 (TX-) - D15-14 (GND) W - W-B Lo-level CAN bus line Ignition switch ON

    Pulse generation

    (see waveform 4)
    D15-13 (SG-2) - Body ground GR - Body ground Ground for pressure sensor and flow sensor Always Below 1.0 Ω
    D15-14 (GND) - Body ground W-B - Body ground Ground for main power supply Always Below 1.0 Ω
    D15-21 (B) - D15-14 (GND) V - W-B Power source (Back-up) Always 11 to 14 V
    D15-22 (PTC2)* - Body ground W - Body ground PTC heater relay operation signal

    Engine idling

    Set temperature: MAX HOT

    Engine coolant temperature: Below 65°C (149°F)

    Ambient temperature: Below 10°C (50°F)

    Blower switch: off → Lo

    		 Below 1 V → 11 to 14 V
    D15-23 (BLW) - D15-14 (GND) GR - W-B Blower motor control signal

    Ignition switch ON

    Blower switch: Lo

    Pulse generation

    (see waveform 2)
    D15-25 (ALT)* - Body ground LG - Body ground Generator signal Engine idling Pulse generation
    D15-27 (HLS)* - Body ground B - Body ground Head light signal

    Engine idling

    Head light switch: on

    		 Below 1.0 Ω
    D15-29 (TR) - D15-34 (SG-1) SB - V Room temperature sensor signal

    Ignition switch ON

    Vehicle interior temperature: 25°C (77°F)

    		 1.8 to 2.2 V
    D15-29 (TR) - D15-34 (SG-1) SB - V Room temperature sensor signal

    Ignition switch ON

    Vehicle interior temperature: 40°C (104°F)

    		 1.2 to 1.6 V
    D15-33 (TS) - Body ground BR - Body ground Solar sensor signal

    Ignition switch ON

    Solar sensor subject to electric light

    		 0.8 to 4.3 V
    D15-33 (TS) - Body ground BR - Body ground Solar sensor signal

    Ignition switch ON

    Solar sensor covered with a cloth

    		 Below 0.8 V
    D15-34 (SG-1) - Body ground V - Body ground Ground for room temperature sensor Always Below 1.0 Ω
    D15-37 (LIN1) - D15-14 (GND) L - W-B LIN communication signal Ignition switch ON Pulse generation
    z1-2 (BUS G) - Body ground - Ground for BUS IC Always Below 1.0 Ω
    z1-3 (BUS) - z1-2 (BUS G) - BUS IC control signal Ignition switch ON Pulse generation
    z1-4 (B BUS) - z1-2 (BUS G) - Power supply for BUS IC Always 11 to 14 V
    z1-5 (SG) - Body ground - Ground for front evaporator temperature sensor Always Below 1.0 Ω
    z1-6 (TE) - z1-5 (SG) - front evaporator temperature sensor signal

    Ignition switch ON

    Evaporator temperature: 0°C (32°F)

    		 2.0 to 2.4 V

    Ignition switch ON

    Evaporator temperature: 15°C (59°F)

    		 1.4 to 1.8 V
    D15-20 (MGC) - D15-14 (GND) B - W-B A/C compressor magnetic clutch operation signal

    Ignition switch ON

    Blower switch Lo

    A/C switch off

    		 11 to 14 V

    Ignition switch ON

    Blower switch Lo

    A/C switch on

    		 Below 1 V
    D15-7 (FLOQ) - D15-13 (SG-2) SB-GR Flow sensor signal

    Blower switch: Lo

    Engine idling

    A/C switch off

    		 3.76 to 4.7 V

    Blower switch: Lo

    Engine idling

    A/C switch on

    		 0.3 to 3.76 V

    • *: w/ PTC heater

    • If the result is not as specified, the ECU may have a malfunction.


    1. A011B68E17

      Waveform 1: Using an oscilloscope

      Air Conditioning Compressor Operation Signal
      Terminal Name Between SOL+ - GND
      Tester Range 5 V/DIV, 500 μs./DIV
      Condition Engine idling, Blower switch LO, A/C switch ON
    2. A011BA5E17

      Waveform 2: Using an oscilloscope.

      Blower Motor Control Signal
      Terminal Name Between BLW - GND
      Tester Range 1 V/DIV, 500 μs./DIV
      Condition Ignition switch ON, Blower switch 1

      Tech Tips

      When the blower level is increased, the duty ratio changes accordingly.

    3. A0119N6E42

      Waveform 3 (Reference): Using an oscilloscope

      CAN Communication Signal
      Terminal Name Between TX+ - GND
      Tester Range 1 V/DIV, 10 μs./DIV
      Condition Ignition switch ON

      Tech Tips

      The waveform varies depending on the CAN communication signal.

    4. A01177ZE39

      Waveform 4 (Reference): Using an oscilloscope

      CAN Communication Signal
      Terminal Name Between TX- - GND
      Tester Range 1 V/DIV, 10 μs./DIV
      Condition Ignition switch ON

      Tech Tips

      The waveform varies depending on the CAN communication signal.

  2. CHECK INSTRUMENT CLUSTER FINISH PANEL ASSEMBLY

    Tech Tips

    Check from the rear of the connector while it is connected to the instrument cluster finish panel assembly.

    A0119CAE01
    Standard
    Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
    D5-5 (IG) - D5-4 (GND) P - W-B Power source (IG) Ignition switch ON 11 to 14 V
    D5-4 (GND)) - Body ground W-B - Body Ground Ground Always Below 1.0 Ω
    D5-3 (LIN1) - D5-4 (GND) L - W-B LIN communication signal Ignition switch ON Pulse generation

    • If the result is not as specified, the instrument cluster finish panel assembly may have a malfunction.

  3. CHECK COMBINATION METER ASSEMBLY

    A0119T8E02

    Tech Tips

    Check from the rear of the connector while it is connected to the combination meter assmebly.

    Standard
    Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
    D1-4 (TX1-) - Body ground V - Body ground Ambient temperature sensor signal

    Ignition switch: ON

    Ambient temperature: 25°C (77°F)

    		 1.5 V
    D1-23 (TX1+) - Body ground L - Body ground Ambient temperature sensor ground Always Below 1.0 Ω

    • If the result is not as specified, the combination meter assembly may have a malfunction.