AIR CONDITIONING SYSTEM TERMINALS OF ECU


  1. AIR CONDITIONING AMPLIFIER ASSEMBLY

    A01FG2JE01

    1. Disconnect the N79 air conditioning amplifier assembly connector.

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      N79-1 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      N79-5 (IG+) - N79-1 (GND) L - W-B Power source (IG) Engine switch on (IG) 11 to 14 V
      N79-5 (IG+) - N79-1 (GND) L - W-B Power source (IG) Engine switch off Below 1 V
      N79-6 (+B1) - N79-1 (GND) W - W-B Power source (Back-up) Always 11 to 14 V
      N79-18 (MGC) - N79-1 (GND) P - W-B Magnet clutch operation signal Engine switch on (IG) 11 to 14 V
      N79-18 (MGC) - N79-1 (GND) P - W-B Magnet clutch operation signal Engine switch off Below 1 V

      Tech Tips

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

    3. Reconnect the N79 air conditioning amplifier assembly connector.

    4. Measure the voltage, resistance and waveform according to the value(s) in the table below.

      Tech Tips

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

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      N79-3 (BLW) - N79-1 (GND) W - W-B Blower motor speed control signal

      Engine switch on (IG)

      Blower switch: Lo

      Pulse generation

      (See waveform 1)
      N79-4 (SOL+) - N79-1 (GND) P - W-B Compressor solenoid operation signal

      Engine running

      Blower switch: Lo

      A/C switch: on (magnet clutch on)

      Pulse generation

      (See waveform 2)
      N79-8 (PTC1) - N79-1 (GND)*1 Y - W-B PTC heater relay operation signal

      Engine running

      Combination switch: off

      Set temperature: HI

      Engine coolant temperature: 69°C (156.2°F) or lower

      Ambient temperature: 3°C (37.4°F) or lower

      Blower switch: off

      		 11 to 14 V
      N79-8 (PTC1) - N79-1 (GND)*1 Y - W-B PTC heater relay operation signal

      Engine running

      Combination switch: off

      Set temperature: HI

      Engine coolant temperature: 69°C (156.2°F) or lower

      Ambient temperature: 3°C (37.4°F) or lower

      Blower switch: Lo or more (after 10 seconds)

      		 Below 1 V
      N79-9 (NANO) - N79-1 (GND)*2 R - W-B Ion generator operation signal

      Engine switch on (IG)

      Blower switch: Lo or more

      Ion generator switch: off

      		 11 to 14 V
      N79-9 (NANO) - N79-1 (GND)*2 R - W-B Ion generator operation signal

      Engine switch on (IG)

      Blower switch: Lo or more

      Ion generator switch: on

      		 Below 1 V
      N79-18 (MGC) - N79-1 (GND) P - W-B Magnet clutch operation signal

      Engine running

      Blower switch: Lo

      A/C switch: off

      		 11 to 14 V
      N79-18 (MGC) - N79-1 (GND) P - W-B Magnet clutch operation signal

      Engine running

      Blower switch: Lo

      A/C switch: on (magnet clutch on permitted)

      		 Below 1 V
      N79-21 (RLIN) - N79-1 (GND)*6 P - W-B LIN communication signal Engine switch on (IG) Pulse generation
      N79-22 (NAIN) - N79-1 (GND)*2 G - W-B Ion generator operation signal

      Engine switch on (IG)

      Blower switch: Lo or more

      Ion generator switch: off

      		 4.75 to 5.25 V
      N79-22 (NAIN) - N79-1 (GND)*2 G - W-B Ion generator operation signal

      Engine switch on (IG)

      Blower switch: Lo or more

      Ion generator switch: on

      		 Below 2.2 V
      N79-26 (PTC2) - N79-1 (GND)*1 B - W-B PTC heater relay operation signal

      Engine running

      Combination switch: off

      Set temperature: HI

      Engine coolant temperature: 69°C (156.2°F) or lower

      Ambient temperature: 3°C (37.4°F) or lower

      Blower switch: off

      		 11 to 14 V
      N79-26 (PTC2) - N79-1 (GND)*1 B - W-B PTC heater relay operation signal

      Engine running

      Combination switch: off

      Set temperature: HI

      Engine coolant temperature: 69°C (156.2°F) or lower

      Ambient temperature: 3°C (37.4°F) or lower

      Blower switch: Lo or more (after 20 seconds)

      		 Below 1 V
      N79-29 (ECOS) - N79-1 (GND) P - W-B Combination switch assembly operation signal

      Engine switch on (IG)

      Combination switch assembly not turned

      		 11 to 14 V
      N79-29 (ECOS) - N79-1 (GND) P - W-B Combination switch assembly operation signal

      Engine switch on (IG)

      Combination switch assembly being turned and held at ECO position

      		 Below 1 V
      N81-1 (SG-1) - Body ground G - Body ground Ground for room temperature sensor Always Below 1 Ω
      N81-3 (CANH) - N81-4 (CANL)*3 R - W CAN communication system CAN communication occurring Pulse generation
      N81-3 (CANH) - N81-4 (CANL)*4 Y - W CAN communication system CAN communication occurring Pulse generation
      N81-5 (S5-1) - N79-1 (GND) R - W-B Power supply for room humidity sensor, glass temperature sensor and glass surroundings temperature sensor Engine switch on (IG) 4.75 to 5.25 V
      N81-7 (TSD) - N79-1 (GND)*3 SB - W-B Solar sensor signal (for Driver side)

      Engine switch on (IG)

      Solar sensor subjected to electric light

      		 0.8 to 4.3 V
      N81-7 (TSD) - N79-1 (GND)*3 SB - W-B Solar sensor signal (for Driver side)

      Engine switch on (IG)

      Solar sensor covered with a cloth

      		 Below 0.8 V
      N81-7 (TSD) - N79-1 (GND)*4 V - W-B Solar sensor signal (for Driver side)

      Engine switch on (IG)

      Solar sensor subjected to electric light

      		 0.8 to 4.3 V
      N81-7 (TSD) - N79-1 (GND)*4 V - W-B Solar sensor signal (for Driver side)

      Engine switch on (IG)

      Solar sensor covered with a cloth

      		 Below 0.8 V
      N81-8 (TSP) - N79-1 (GND)*3 V - W-B Solar sensor signal (for Front passenger side)

      Engine switch on (IG)

      Solar sensor subjected to electric light

      		 0.8 to 4.3 V
      N81-8 (TSP) - N79-1 (GND)*3 V - W-B Solar sensor signal (for Front passenger side)

      Engine switch on (IG)

      Solar sensor covered with a cloth

      		 Below 0.8 V
      N81-8 (TSP) - N79-1 (GND)*4 SB - W-B Solar sensor signal (for Front passenger side)

      Engine switch on (IG)

      Solar sensor subjected to electric light

      		 0.8 to 4.3 V
      N81-8 (TSP) - N79-1 (GND)*4 SB - W-B Solar sensor signal (for Front passenger side)

      Engine switch on (IG)

      Solar sensor covered with a cloth

      		 Below 0.8 V
      N81-9 (PRE) - N81-32 (SG-2) P - GR Air conditioning pressure sensor signal

      Engine running

      Blower switch: Lo

      A/C switch: on (magnet clutch on)

      Refrigerant pressure: normal pressure (more than 0.19 MPa [2.0 kgf/cm2, 28 psi] to less than 3.14 MPa [32.0 kgf/cm2, 455 psi])

      		 0.63 to 4.73 V
      N81-10 (TAM) - N81-32 (SG-2) V - GR Ambient temperature sensor signal

      Engine switch on (IG)

      Ambient temperature: 25°C (77°F)

      		 1.35 to 1.75 V
      N81-13 (S5-3) - N81-32 (SG-2) LG - GR Power supply for flow sensor Engine switch off Below 1 V
      N81-13 (S5-3) - N81-32 (SG-2) LG - GR Power supply for flow sensor Engine switch on (IG) 4.75 to 5.25 V
      N81-15 (FLOQ) - N81-32 (SG-2) R - GR Flow sensor signal

      Engine switch on (IG)

      A/C switch: off

      Blower switch: off

      		 3.8 to 4.2 V
      N81-15 (FLOQ) - N81-32 (SG-2) R - GR Flow sensor signal

      Engine switch on (IG)

      A/C switch: on (magnet clutch on)

      Blower switch: Hi

      		 0.7 to 3.8 V
      N81-16 (TR) - N81-1 (SG-1) P - G Room temperature sensor signal

      Engine switch on (IG)

      Cabin temperature: 25°C (77°F)

      		 1.8 to 2.2 V
      N81-21 (TNG) - N81-33 (SG-5) GR - SB Glass surroundings temperature sensor signal

      Engine switch on (IG)

      Glass surroundings temperature: 25°C (77°F)

      		 3.65 to 3.69 kΩ
      N81-22 (TFG) - N81-33 (SG-5) V - SB Glass temperature sensor signal

      Engine switch on (IG)

      Glass temperature: 25°C (77°F)

      		 3.65 to 3.69 kΩ
      N81-23 (RH) - N81-33 (SG-5) Y - SB Room humidity sensor signal

      Engine switch on (IG)

      Cabin temperature: 25°C (77°F)

      Glass humidity: 40%

      		 2.09 V
      N81-23 (RH) - N81-33 (SG-5) Y - SB Room humidity sensor signal

      Engine switch on (IG)

      Cabin temperature: 25°C (77°F)

      Glass humidity: 60%

      		 2.81 V
      N81-24 (DGS) - N81-32 (SG-2)*5 R - GR Smog ventilation sensor signal (CO, HC)

      Engine switch on (IG)

      Cabin temperature: 20°C (68°F)

      Glass humidity: 60%

      Spray the clean air

      		 15 to 40 kΩ
      N81-24 (DGS) - N81-32 (SG-2)*5 R - GR Smog ventilation sensor signal (CO, HC)

      Engine switch on (IG)

      Cabin temperature: 20°C (68°F)

      Glass humidity: 40%

      Spray the clean air

      		 1.5 to 240 kΩ
      N81-25 (DGS1) - N81-32 (SG-2)*5 L - GR Smog ventilation sensor signal (NOx)

      Engine switch on (IG)

      Cabin temperature: 20°C (68°F)

      Glass humidity: 65%

      Spray the clean air

      		 2.5 to 40 kΩ
      N81-30 (LOCK) - N81-32 (SG-2) L - GR Compressor lock sensor operation signal

      Engine running

      Blower switch: Lo

      A/C switch: on (magnet clutch on)

      Pulse generation

      (See waveform 3)
      N81-32 (SG-2) - Body ground GR - Body ground Ground for air conditioning pressure sensor, ambient temperature sensor, flow sensor, compressor lock sensor and smog ventilation sensor*5 Always Below 1 Ω
      N81-33 (SG-5) - Body ground SB - Body ground Ground for room humidity sensor, glass temperature sensor and glass surroundings temperature sensor Always Below 1 Ω
      z1-1 (BUS G) - Body ground - Ground for BUS IC Always Below 1 Ω
      z1-2 (BUS) - z1-1 (BUS G) - BUS IC control signal Engine switch on (IG)

      Pulse generation

      (See waveform 4)
      z1-3 (B BUS) - z1-1 (BUS G) - Power supply for BUS IC Always 11 to 14 V
      z1-12 (SGA) - Body ground - Ground for evaporator temperature sensor Always Below 1 V
      z1-11 (TEA) - z1-12 (SGA) - Evaporator temperature sensor signal

      Engine switch on (IG)

      Evaporator temperature: 0°C (32°F)

      		 2.0 to 2.4 V
      z1-11 (TEA) - z1-12 (SGA) - Evaporator temperature sensor signal

      Engine switch on (IG)

      Evaporator temperature: 15°C (59°F)

      		 1.4 to 1.8 V

      • *1: w/ PTC Heater

      • *2: w/ Ion Generator

      • *3: for LHD

      • *4: for RHD

      • *5: w/ Smog Ventilation Sensor

      • *6: w/ Rear Control Switch

    5. A01FDKOE01

      Waveform 1:

      Item Content
      Terminal No. (Symbol) N79-3 (BLW) - N79-1 (GND)
      Tool Setting 1 V/DIV., 500 μs/DIV.
      Vehicle Condition

      Engine switch on (IG)

      Blower switch: Lo
    6. A01FFOLE02

      Waveform 2:

      Item Content
      Terminal No. (Symbol) N79-4 (SOL+) - N79-1 (GND)
      Tool Setting 5 V/DIV., 500 μs/DIV.
      Vehicle Condition

      Engine running

      Blower switch: Lo

      A/C switch: on (magnet clutch on)
    7. A01FHLBE01

      Waveform 3:

      Item Content
      Terminal No. (Symbol) N81-30 (LOCK) - N81-32 (SG-2)
      Tool Setting 200 mV/DIV., 10 ms./DIV.
      Vehicle Condition

      Engine running

      Blower switch: Lo

      A/C switch: on (magnet clutch on)
    8. A01FFALE01

      Waveform 4:

      Item Content
      Terminal No. (Symbol) z1-2 (BUS) - z1-1 (BUS G)
      Tool Setting 1 V/DIV., 2 ms./DIV.
      Vehicle Condition Engine switch on (IG)

  2. Rear Control Switch (w/ Rear Control Switch)

    A01FF43E01

    1. Disconnect the Z1 rear control switch connector.

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      Z1-1 (+B) - Z1-5 (E) R - W-B Power source (Back-up) Always 11 to 14 V
      Z1-5 (E) - Body ground W-B - Body ground Ground Always Below 1 Ω
      Z1-7 (IG+) - Z1-5 (E) L - W-B Power source (IG) Engine switch off Below 1 V
      Z1-7 (IG+) - Z1-5 (E) L - W-B Power source (IG) Engine switch on (IG) 11 to 14 V

      Tech Tips

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

    3. Reconnect the Z1 rear control switch connector.

    4. Measure the waveform according to the value(s) in the table below.

      Tech Tips

      Check from the rear of the connector while it is connected to the rear control switch.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      Z1-9 (RLIN) - Z1-5 (E) P - W-B LIN communication signal Engine switch on (IG) Pulse generation