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


  1. AIR CONDITIONING AMPLIFIER ASSEMBLY (w/o PTC Heater)

    B0027SGN02

    1. Disconnect the G34 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
      G34-7 (IG+) - Body ground G - Body ground Power source (IG) Ignition switch off Below 1 V
      Ignition switch ON 11 to 14 V
      G34-11 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω

    3. Reconnect the G34 air conditioning amplifier assembly connector.

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

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      G34-2 (AC1) - Body ground GR - Body ground Idle-up request signal

      • Engine running

      • Blower switch: LO or higher

      • "A/C" switch: Off

      		 11 to 14 V

      • Engine running

      • Blower switch: LO or higher

      • "A/C" switch: On

      		 Below 1 V
      G34-3 (PSW) - Body ground L - Body ground Air conditioner pressure sensor signal

      • Engine running

      • Refrigerant pressure normal

      • Blower switch: LO or higher

      • "A/C" switch: On

      		 Below 1 V

      • Engine running

      • Refrigerant pressure abnormal (below 0.176 MPa [1.8 kgf/cm2, 25.5 psi] or higher than 3.025 MPa [30.9 kgf/cm2, 438.6 psi])

      • Blower switch: LO or higher

      • "A/C" switch: On

      		 11 to 14 V
      G34-4 (ACT) - Body ground LG - Body ground Magnet clutch on permit signal

      • Engine running

      • Blower switch: LO or higher

      • "A/C" switch: On (magnet clutch on)

      		 4.5 to 5.5 V

      • Engine running

      • Blower switch: LO or higher

      • "A/C" switch: Off or on (magnet clutch off)

      		 Below 1 V
      G34-5 (SG-2) - Body ground L - Body ground Ground for No. 1 cooler thermistor Always Below 1 Ω
      G34-6 (TE) - Body ground P - Body ground No. 1 cooler thermistor signal Evaporator temperature (ambient): 0°C (32°F) 1.7 to 2.1 V
      Evaporator temperature (ambient): 15°C (59°F) 1.0 to 1.3 V
      Evaporator temperature (ambient): 20°C (68°F) 0.8 to 1.1 V
      Evaporator temperature (ambient): 25°C (77°F) 0.6 to 0.9 V
      Evaporator temperature (ambient): 30°C (86°F) 0.5 to 0.8 V
      G34-9 (A/C) - Body ground B - Body ground Blower switch signal

      • Ignition switch ON

      • Blower switch: LO or higher

      • "A/C" switch: On

      		 Below 1 V

      • Ignition switch ON

      • Blower switch: LO or higher

      • "A/C" switch: Off

      		 11 to 14 V
      G34-10 (MGC) - Body ground V - Body ground Cooler compressor assembly operation signal

      • Engine running

      • Blower switch set to LO or higher

      • "A/C" switch: Off or on (magnet clutch off)

      		 11 to 14 V

      • Engine running

      • Blower switch set to LO or higher

      • "A/C" switch: On (magnet clutch on)

      		 Below 1 V

  2. AIR CONDITIONING AMPLIFIER ASSEMBLY (w/ PTC Heater)

    B0026YRN02

    1. Disconnect the G77 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
      G77-1 (IG+) - Body ground G - Body ground Power source (IG) Ignition switch off Below 1 V
      Ignition switch ON 11 to 14 V
      G77-23 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω

    3. Reconnect the G77 air conditioning amplifier assembly connector.

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

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      G77-2 (SWVC) - Body ground*1, *2 R - Body ground

      • Heater switch assembly operation signal*1

      • Idle up switch operation signal*2

      • Engine running

      • Heater switch assembly: Off → on*1

      • Idle up switch: Off → on*2

      		 Below 1 V → 11 to 14 V
      G77-3 (HEAT) - Body ground G - Body ground Blower switch signal

      • Engine running

      • Blower switch: Off

      		 Below 1 V

      • Engine running

      • Blower switch: On

      		 11 to 14 V
      G77-4 (TE) - Body ground P - Body ground No. 1 cooler thermistor signal Evaporator temperature (ambient): 0°C (32°F) 1.7 to 2.1 V
      Evaporator temperature (ambient): 15°C (59°F) 1.0 to 1.3 V
      Evaporator temperature (ambient): 20°C (68°F) 0.8 to 1.1 V
      Evaporator temperature (ambient): 25°C (77°F) 0.6 to 0.9 V
      Evaporator temperature (ambient): 30°C (86°F) 0.5 to 0.8 V
      G77-5 (SG-2) - Body ground L - Body ground Ground for No. 1 cooler thermistor Always Below 1 Ω
      G77-6 (VER2) - Body ground*1 W-B - Body ground Ground Always Below 1 Ω
      G77-7 (A/C) - Body ground B - Body ground Blower switch signal

      • Ignition switch ON

      • Blower switch: LO or higher

      • "A/C" switch: On

      		 11 to 14 V

      • Ignition switch ON

      • Blower switch: LO or higher

      • "A/C" switch: Off

      		 Below 1 V
      G77-12 (AC1) - Body ground GR - Body ground Idle-up request signal

      • Engine running

      • Blower switch: LO

      • "A/C" switch: Off

      		 11 to 14 V

      • Engine running

      • Blower switch: LO

      • "A/C" switch: On

      		 Below 1 V
      G77-13 (PTC1) - Body ground L - Body ground Quick heater assembly operation signal

      • Engine starts

      • ECO mode switch: Off

      • Temperature settings: MAX HOT

      • Ambient temperature: 10°C (50°F) or lower

      • Engine coolant temperature: 64°C (147°F) or lower

      • Light control switch: Off

      • Blower switch: Off → on (after 10 seconds)

      		 11 to 14 V → Below 1 V
      G77-16 (MGC) - Body ground V - Body ground Cooler compressor assembly operation signal

      • Engine running

      • Blower switch: LO or higher

      • "A/C" switch: Off or on (magnet clutch off)

      		 11 to 14 V

      • Engine running

      • Blower switch: LO or higher

      • "A/C" switch: On (magnet clutch on)

      		 Below 1 V
      G77-17 (PSW) - Body ground L - Body ground Air conditioner pressure sensor signal

      • Engine running

      • Refrigerant pressure normal

      		 Below 1 V

      • Engine running

      • Refrigerant pressure abnormal (below 0.176 MPa [1.8 kgf/cm2, 25.5 psi] or higher than 3.025 MPa [30.9 kgf/cm2, 438.6 psi])

      		 11 to 14 V
      G77-18 (ACT) - Body ground LG - Body ground Magnet clutch on permit signal

      • Engine running

      • Blower switch: LO or higher

      • "A/C" switch: On (magnet clutch on)

      		 4.5 to 5.5 V

      • Engine running

      • Blower switch: LO or higher

      • "A/C" switch: Off or on (magnet clutch off)

      		 Below 1 V
      G77-19 (PTC2) - Body ground W - Body ground Quick heater assembly operation signal

      • Engine starts

      • ECO mode switch: Off

      • Temperature settings: MAX HOT

      • Ambient temperature: 10°C (50°F) or lower

      • Engine coolant temperature: 64°C (147°F) or lower

      • Light control switch: Off

      • Blower switch: Off → on (after 20 seconds)

      		 11 to 14 V → Below 1 V
      G77-20 (PTC3) - Body ground SB - Body ground Quick heater assembly operation signal

      • Engine starts

      • ECO mode switch: Off

      • Temperature settings: MAX HOT

      • Ambient temperature: 10°C (50°F) or lower

      • Engine coolant temperature: 64°C (147°F) or lower

      • Light control switch: Off

      • Blower switch: Off → on (after 30 seconds)

      		 11 to 14 V → Below 1 V
      G77-23 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω

      • *1: w/ Viscous Heater

      • *2: w/ Idle Up Switch

  3. ECM