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


  1. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY

    A005IO3E02

    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
    F42-1 (IG+) - F42-14 (GND) V - W-B Power source (IG) Ignition switch ON 11 to 14 V
    F42-2 (SOL+) - F42-14 (GND) P - W-B A/C compressor operation signal Engine idling

    Pulse generation

    (see waveform 1)
    Blower switch: LO
    A/C switch: ON
    F42-5 (TAM)*1 - F42-13 (SG-2) W - L A/C ambient temperature sensor signal Ignition switch ON at 25°C (77°F) 1.35 to 1.75V
    F42-9 (PRE) - F42-14 (GND) GR - W-B Air conditioning pressure sensor signal Refrigerant pressure: Normal 0.74 to 4.62 V

    Refrigerant pressure: Abnormal (less than 0.176 MPa [1.8 kgf/cm2]) or more than 3.03 MPa [31 kgf/cm2])

    		 Below 0.74 V or 4.62 V or more
    F42-10 (S5-3) - F42-14 (GND) Y - W-B Power supply for pressure sensor Ignition switch ON 4.75 to 5.25 V
    F42-11 (TX+) - F42-14 (GND) V - W-B Hi-level CAN bus line Ignition switch ON

    Pulse generation

    (see waveform 3)
    F42-12 (TX-) - F42-14 (GND) W - W-B Lo-level CAN bus line Ignition switch ON

    Pulse generation

    (see waveform 4)
    F42-13 (SG-2) - Body ground L - Body ground Ground for pressure sensor Always Below 1 Ω
    F42-14 (GND) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω
    F42-21 (B) - F42-14 (GND) BE - W-B Power source (Back-up) Always 11 to 14 V
    F42-40 (PTC1)*2 - Body ground V - Body ground PTC heater relay operation signal Engine idling Below 1 V → 11 to 14 V
    Set temperature: MAX HOT
    Engine coolant temperature: Below 75°C (167°F)
    Ambient temperature: Below 10°C (50°F)
    Blower switch: OFF → LO
    F42-39 (PTC2)*2 - Body ground P - Body ground PTC heater relay operation signal Engine idling Below 1 V → 11 to 14 V
    Set temperature: MAX HOT
    Engine coolant temperature: Below 70°C (158°F)
    Ambient temperature: Below 10°C (50°F)
    Blower switch: OFF → LO
    F42-3 (PTC3)*2 - Body ground Y - Body ground PTC heater relay operation signal Engine idling Below 1 V → 11 to 14 V
    Set temperature: MAX HOT
    Engine coolant temperature: Below 65°C (149°F)
    Ambient temperature: Below 10°C (50°F)
    Blower switch: OFF → LO
    F42-22 (BLW) - F42-14 (GND) R - W-B Blower motor control signal Ignition switch ON

    Pulse generation

    (see waveform 2)
    Blower switch: LO
    F42-29 (TR) - F42-34 (SG-1) P - SB Room temperature sensor signal Ignition switch ON 1.8 to 2.2 V
    Vehicle interior temperature: 25°C
    F42-33 (TSD) - F42-14 (GND) R - W-B Passenger side solar sensor signal Ignition switch ON 0.8 to 4.3 V
    Solar sensor subject to electric light
    F42-34 (SG-1) - Body ground SB - Body ground Ground for room temperature sensor Always Below 1 Ω
    F42-13 (SG-2) - F42-14 (GND) L - W-B Ground for pressure sensor Always Below 1 Ω
    F42-37 (LIN1) - F42-14 (GND) LG - W-B LIN communication signal Ignition switch ON Pulse generation
    z4-2 (BUSG) - Body ground - Ground for BUS IC Always Below 1 Ω
    z4-3 (BUS) - z4-2 (BUSG) - BUS IC control signal Ignition switch ON Pulse generation
    z4-4 (BBUS) - z4-2 (BUSG) - Power supply for BUS IC Always 11 to 14 V
    z4-5 (SGA) - Body ground - Ground for evaporator temperature sensor Always Below 1 Ω
    z4-6 (TEA) - z4-5 (SGA) - Evaporator temperature sensor signal Ignition switch ON 1.4 to 1.8 V
    Evaporator temperature: 15°C (59°F)

    *1: w/o Rear Fog Light

    *2: w/ Quick Heater Assembly

    If the result is not as specified, there may be a malfunction in the wire harness.


    1. A005HFTE01
      *a 5 V/DIV.
      *b 500 μsec/DIV.

      Waveform 1: Using an oscilloscope

      Compressor and Pulley Operation Signal
      Terminal Name F42-2 (SOL+) - F42-14 (GND)
      Tester Range 5 V/DIV, 500 μs/DIV
      Condition Engine idling, Blower switch LO, A/C switch ON
    2. A005GYOE36
      *a 1 V/DIV.
      *b 500 μsec/DIV.

      Waveform 2: Using an oscilloscope.

      Blower Motor Control Signal
      Terminal Name F42-22 (BLW) - F42-14 (GND)
      Tester Range 1 V/DIV, 500 μs/DIV
      Condition Ignition switch ON, Blower switch LO, A/C switch ON

      Tech Tips

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

    3. A005JWRE01
      *a 1 V/DIV.
      *b 10 μsec./DIV.

      Waveform 3 (Reference) : Using an oscilloscope

      CAN Communication Signal
      Terminal Name F42-11 (TX+) - F42-14 (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. A005H9SE01
      *a 1 V/DIV.
      *b 10 μsec./DIV.

      Waveform 4 (Reference) : Using an oscilloscope

      CAN Communication Signal
      Terminal Name F42-12 (TX-) - F42-14 (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 AIR CONDITIONING CONTROL ASSEMBLY

    A005HMSE02
    Standard
    Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
    F40-5 (IG+) - F40-8 (GND) V - BR Power source (IG) Ignition switch ON 11 to 14 V
    F40-2 (LIN1) - F40-8 (GND) LG - BR LIN communication signal Ignition switch ON Pulse generation
    F40-8 (GND) - Body ground BR - Body Ground Ground for air conditioning control assembly Always Below 1 Ω

    If the result is not as specified, there may be a malfunction in the wire harness.

  3. CHECK COMBINATION METER ASSEMBLY

    A005LLEE02
    Standard
    Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
    F1-39 (IG+) - Body ground P - Body ground Power source (IG) Ignition switch ON 11 to 14 V
    F1-40 (B) - Body ground L - Body ground Power source (Back-up) Always 11 to 14 V
    F1-34 (TX1-) - F1-35 (TX1+)* B - W Ambient temperature sensor signal Ignition switch ON at 25°C (77°F) 1.35 to 1.75 V

    *: w/ Rear Fog Light

    If the result is not as specified, there may be a malfunction in the wire harness.