AIR CONDITIONING SYSTEM TERMINALS OF ECU

AIR CONDITIONING AMPLIFIER ASSEMBLY

1. Disconnect the G81 air conditioning amplifier assembly connector.

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

   Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
   G81-1 (IG+) - Body ground	GR - Body ground	Power source (IG)	Power switch on (IG)	11 to 14 V
   			Power switch off	Below 1 V
   G81-14 (GND) - Body ground	W-B - Body ground	Ground for main power supply	Always	Below 1 Ω
   G81-21 (B) - Body ground	GR - Body ground	Power source (Back-up)	Power switch off	11 to 14 V

3. Reconnect the G81 air conditioning amplifier assembly connector.

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

   Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
   G81-3 (PTC2) - G81-14 (GND)	BR - W-B	Quick heater assembly operation signal	Power switch on (READY) Driving module switch assembly (ECO mode switch) off Temperature settings: MAX HOT Ambient temperature: 10°C (50°F) or lower Engine coolant temperature: 60°C (140°F) or lower IDH terminal signal less than 1 V (Inverter with converter assembly overload not detected) Blower switch: LO	Below 1 V
   			Power switch on (READY) Driving module switch assembly (ECO mode switch) off Temperature settings: MAX HOT Ambient temperature: 10°C (50°F) or lower Engine coolant temperature: 60°C (140°F) or lower IDH terminal signal less than 1 V (Inverter with converter assembly overload not detected) Blower switch: off	11 to 14 V
   G81-9 (PRE) - G81-10 (S5-3)	BE - B	Air conditioner pressure sensor signal	Engine running Air conditioning system operating Refrigerant pressure: Abnormal pressure (higher than 3025 kPa [30.8 kgf/cm2, 439 psi])	4.73 V or higher
   			Engine running Refrigerant pressure: Abnormal pressure (below 176 kPa [1.8 kgf/cm2, 26 psi]) Air conditioning system operating	Below 0.62 V
   			Engine running Air conditioning system operating Refrigerant pressure: Normal pressure (below 3025 kPa [30.8 kgf/cm2, 439 psi] and higher than 176 kPa [1.8 kgf/cm2, 26 psi])	0.62 to 4.73 V
   G81-10 (S5-3) - Body ground	B - Body ground	Ground for air conditioner pressure sensor, ambient temperature sensor, air conditioning lock sensor	Always	Below 1 Ω
   G81-11 (CANH)	B	CAN communication line	-	-
   G81-12 (CANL)	W	CAN communication line	-	-
   G81-13 (SG-2) - Body ground	G - Body ground	Ground for ambient temperature sensor signal	Always	Below 1 Ω
   G81-22 (BLW) - Body ground	R - Body ground	Blower motor speed control signal	Power switch on (IG) Blower switch LO	Pulse generation (See Waveform 1)
   G81-24 (ECOS) - Body ground*	R - Body ground	Combination switch assembly (ECO mode switch) signal	Power switch on (IG) Combination switch assembly (ECO mode switch) on	Below 1 V
   			Power switch on (IG) Combination switch assembly (ECO mode switch) off	11 to 14 V
   G81-27 (IDH) - G81-14 (GND)	W - W-B	Inverter with converter assembly current over signal	Power switch on (IG) Quick heater assembly operation permitted	Below 1 V
   			Power switch on (IG) Quick heater assembly operation not permitted	4.75 to 5.25 V
   G81-29 (TR) - G81-34 (SG-1)	GR - V	Room temperature sensor signal	Power switch on (IG) Cabin temperature: 25°C (77°F)	1.8 to 2.2 V
   			Power switch on (IG) Cabin temperature: 40°C (104°F)	1.2 to 1.6 V
   G81-34 (SG-1) - Body ground	V - Body ground	Ground for room temperature sensor	Always	Below 1 Ω
   G81-37 (LIN1) - Body ground	B - Body ground	LIN communication signal	Power switch on (IG)	Pulse generation
   G81-39 (PTC3) - G81-14 (GND)	R - W-B	Quick heater assembly operation signal	Power switch on (READY) Driving module switch assembly (ECO mode switch) off Temperature settings: MAX HOT Ambient temperature: 10°C (50°F) or lower Engine coolant temperature: 60°C (140°F) or lower IDH terminal signal less than 1 V (Inverter with converter assembly overload not detected) Blower switch: LO	Below 1 V
   			Power switch on (READY) Driving module switch assembly (ECO mode switch) off Temperature settings: MAX HOT Ambient temperature: 10°C (50°F) or lower Engine coolant temperature: 60°C (140°F) or lower IDH terminal signal less than 1 V (Inverter with converter assembly overload not detected) Blower switch: off	11 to 14 V
   G81-40 (PTC1) - G81-14 (GND)	GR - W-B	Quick heater assembly operation signal	Power switch on (READY) Driving module switch assembly (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 IDH terminal signal less than 1 V (Inverter with converter assembly overload not detected) Blower switch: LO	Below 1 V
   			Power switch on (READY) Driving module switch assembly (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 IDH terminal signal less than 1 V (Inverter with converter assembly overload not detected) Blower switch: off	11 to 14 V
   z7-2 (BUS G) - Body ground	-	Ground for BUS IC	Always	Below 1 V
   z7-3 (BUS) - z7-2 (BUS G)	-	BUS IC control signal	Power switch on (IG)	Pulse generation (See Waveform 1)
   z7-4 (B BUS) - z7-2 (BUS G)	-	Power supply for BUS IC	Always	11 to 14 V
   z7-5 (SGA) - Body ground	-	Ground for evaporator temperature sensor	Always	Below 1 V
   z7-6 (TEA) - z7-5 (SGA)	-	Evaporator temperature sensor signal	Power switch on (IG) Evaporator temperature: 0°C (32°F)	1.7 to 2.1 V
   z7-6 (TEA) - z7-5 (SGA)	-	Evaporator temperature sensor signal	Power switch on (IG) Evaporator temperature: 15°C (59°F)	0.9 to 1.3 V

   • w/ ECO Switch

5. 

   Waveform 1:

   Item	Content
   Terminal No.	G81-22 (BLW) - Body ground
   Tool Setting	1 V/DIV., 500 μs/DIV.
   Vehicle Condition	Power switch on (IG) Blower switch LO

6. 

   Waveform 2:

   Item	Content
   Terminal No.	z7-3 (BUS) - z7-2 (BUS G)
   Tool Setting	2 V/DIV., 2 ms/DIV.
   Vehicle Condition	Power switch on (IG)

HYBRID VEHCILE CONTROL ECU

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