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


  1. CHECK AIR CONDITIONING AMPLIFIER

    A017D8AE04

    1. Measure the voltage of the connectors.

      Tech Tips

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

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      D33-1 (IG+) - D33-14 (GND) GR - W-B Power source (IG) Ignition switch on (IG) 11 to 14 V
      D33-2 (SOL+) - D33-14 (GND) L - W-B A/C compressor operation signal Engine idling

      Pulse generation

      (see waveform 1)
      Blower switch LO
      A/C switch ON
      D33-3 (PTC1) - Body ground (*1) P - Body ground PTC NO. 1 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
      D33-4 (PTC3) - Body ground (*1) W - Body ground PTC NO. 3 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
      D33-5 (TAM) - D33-14 (GND) B - W-B Ambient temperature sensor signal Ignition switch on (IG) 1.8 to 2.2 V
      Ambient temperature: 25°C (77°F)
      D33-8 (LOCK) - D33-14 (GND) V - W-B Air compressor lock sensor signal Engine idling

      Pulse generation

      (see waveform 5)
      A/C switch ON
      Blower switch LO
      D33-9 (PRE) - D33-13 (SG-2) R - SB Air conditioning pressure sensor signal Refrigerant pressure: Normal 0.76 to 4.74 V
      D33-9 (PRE) - D33-13 (SG-2) R - SB Air conditioning pressure sensor signal

      Refrigerant pressure: Abnormal (less than 0.196 MPa [2.0 kgf/cm2, 28 psi])

      		 0.5 to 4.83 V
      D33-9 (PRE) - D33-13 (SG-2) R - SB Air conditioning pressure sensor signal

      Refrigerant pressure: Abnormal (more than 3.14 MPa [32 kgf/cm2, 455 psi])

      		 4.74 V or higher
      D33-10 (S5-3) - D33-14 (GND) O - W-B Power supply for pressure sensor Ignition switch on (IG) 4.5 to 5.5 V
      D33-11 (CANH) - D33-14 (GND) LG - W-B Hi-level CAN bus line Ignition switch on (IG)

      Pulse generation

      (see waveform 3)
      D33-12 (CANL) - D33-14 (GND) W - W-B Lo-level CAN bus line Ignition switch on (IG)

      Pulse generation

      (see waveform 4)
      D33-13 (SG-2) - Body ground SB - Body ground Ground for pressure sensor Always Below 1 V
      D33-14 (GND) - Body ground W-B - Body ground Ground for main power supply Always Below 1 V
      D33-20 (MGC) - D33-14 (GND) V - W-B A/C compressor magnetic clutch operation signal Engine idling Below 1 V
      Blower switch LO
      A/C switch ON
      D33-21 (B) - D33-14 (GND) B - W-B Power source (Back-up) Always 11 to 14 V
      D33-22 (PTC2) - Body ground (*1) G - Body ground PTC NO. 2 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
      D33-23 (BLW) - D33-14 (GND) R - W-B Blower motor control signal Ignition switch on (IG)

      Pulse generation

      (see waveform 2)
      Blower switch LO
      D33-25 (ALT) - Body ground (*1) SB - Body ground Generator signal Engine idling Pulse generation
      D33-27 (HLS) - Body ground (*1) V - Body ground Headlight signal Engine idling Below 1 V
      Headlight switch ON
      D33-37 (LIN1) - D33-14 (GND) R - W-B LIN communication signal Ignition switch on (IG) Pulse generation
      D33-38 (RDEF) - D33-14 (GND) W - W-B Rear defogger switch signal

      Ignition switch on (IG)

      Rear defogger switch OFF

      		 11 to 14 V
      D34-1 (RBUS) - D34-21 (RBUG) (*2) R - V BUS IC control signal (for Rear) Ignition switch on (IG) Pulse generation
      D34-4 (TEC) - D34-19 (SGND) (*2) B - GR Evaporator temperature sensor signal (for Rear) Ignition seitch on (IG) 1.4 to 1.8 V
      Evaporator temperature: 15°C (59°F)
      D34-13 (BLIN) - D34-20 (GND2) (*2) B - SB LIN communication signal (for Rear) Ignition switch on (IG) Pulse generation
      D34-19 (SGND) - Body ground (*2) GR - Body ground Ground for evaporator temperature sensor signal (for Rear) Always Below 1 V
      D34-20 (GND2) - Body ground (*2) SB - Body ground Ground for power supply Always Below 1 V
      D34-21 (RBUG) - Body ground (*2) V - Body ground Ground for BUS IC (for Rear) Always Below 1 V
      D34-22 (BLWH) - D34-20 (GND2) (*2) G - SB Blower motor control signal (for Rear) Ignition switch on (IG) Pulse generation
      Blower switch LO
      D34-23 (RBBU) - D34-21 (RBUG) (*2) Y - V Power supply for BUS IC (for Rear) Ignition switch on (IG) 11 to 14 V
      D34-24 (+B2) - D34-20 (GND2) (*2) LG - SB Power source (Back-up) (for Rear) Always 11 to 14 V
      z17-2 (BUS G) - Body ground - Ground for BUS IC Always Below 1 V
      z17-3 (BUS) - z17-2 (BUS G) - BUS IC control signal Ignition switch on (IG) Pulse generation
      z17-4 (B BUS) - z17-2 (BUS G) - Power supply for BUS IC Ignition switch on (IG) 11 to 14 V
      z17-5 (SG) - Body ground - Ground for evaporator temperature sensor Always Below 1 V
      z17-6 (TE) - z17-5 (SG) - Evaporator temperature sensor signal Ignition switch on (IG) 1.4 to 1.8 V
      Evaporator temperature: 15°C (59°F)
    2. A017ECSE11

      Using an oscilloscope, check waveform 1.

      Compressor and pulley operation signal
      Item Content
      Tester Connection D33-2 (SOL+) - D33-14 (GND)
      Tool Setting 5 V/DIV., 500 μsec./DIV.
      Condition Engine idling, Blower switch LO, A/C switch ON
    3. A017DS6E05

      Using an oscilloscope, check waveform 2.

      Blower motor control signal
      Item Content
      Tester Connection D33-23 (BLW) - D33-14 (GND)
      Tool Setting 1 V/DIV., 500 μsec./DIV.
      Condition Ignition switch on (IG), Blower switch LO

      Tech Tips

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

    4. A017EPVE10

      Using an oscilloscope, check waveform 3.

      CAN communication signal
      Item Content
      Tester Connection D33-11 (CANH) - D33-14 (GND)
      Tool Setting 1 V/DIV., 10 μsec./DIV.
      Condition Ignition switch on (IG)

      Tech Tips

      The waveform varies depending on the CAN communication signal.

    5. A017B5TE11

      Using an oscilloscope, check waveform 4.

      CAN communication signal
      Item Content
      Tester Connection D33-12 (CANL) - D33-14 (GND)
      Tool Setting 1 V/DIV., 10 μsec./DIV.
      Condition Ignition switch on (IG)

      Tech Tips

      The waveform varies depending on the CAN communication signal.

    6. A017COTE01

      Using an oscilloscope, check waveform 5.

      A/C compressor lock sensor signal
      Item Content
      Tester Connection D33-8 (LOCK) - D33-14 (GND)
      Tool Setting 200 mV/DIV., 10 ms./DIV.
      Condition

      Engine is running

      Blower switch: LO

      A/C switch: ON

      Tech Tips

      The waveform varies depending on the CAN communication signal.

      *1: w/ PTC Heater

      *2: w/ for Rear Air Conditioning

  2. CHECK FRONT AIR CONDITIONING CONTROL

    A017E2GE04

    1. Measure the voltage of the connectors.

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      E8-1 (IG+) - E8-6 (GND) V - GR Power source (IG) Ignition switch on (IG) 11 to 14 V
      E8-3 (LIN1) - E8-6 (GND) R - GR LIN communication signal LIN switch on (IG) Pulse generation
      E8-6 (GND) - Body ground GR - Body ground Ground for front air conditioning control Always Below 1 V

  3. CHECK REAR AIR CONDITIONING CONTROL (for Rear Air Conditioning)

    A017E2GE02

    1. Measure the voltage of the connectors.

      Tester Connection Wiring Color Terminal Description Condition Specified Condition
      R1-7 (IG+) - R1-12 (E) V - W-B Power source (IG) Ignition switch on (IG) 11 to 14 V
      R1-5 (MPX-) - R1-12 (E) B - W-B LIN communication signal LIN switch on (IG) Pulse generation
      R1-12 (E) - Body ground W-B - Body ground Ground for front air conditioning control Always Below 1 V