ECM Terminal Arrangement

Air conditioner control assembly

Fig 1: Identifying Air Conditioner Control assembly Terminals

Courtesy of SUBARU OF AMERICA, INC.

Standard value

CONNECTOR D19

Terminal No. (Terminal symbol)	Input/Output	Item	Measuring conditions	Standard value
D19-1 (ACC)←→D19-16 (GND)	Input	Voltage	IG ACC	10 to 16 V
D19-2(PSW)←→D19-6 (SG)	Input	Waveform	When refrigerant pressure is normal	10 to 16 V
D19-2(PSW)←→D19-6 (SG)	Input	Waveform	When refrigerant pressure is abnormal	Less than 1 V
D19-6 (SG) ←→Chassis ground	-	Resistance	Always	Less than 1 Ω
D19-8 (HR)←→D19-16 (GND)	Input	Voltage	IG ON Blower switch OFF →LO	Less than 1 V →10 to 16 V
D19-9 (+B)←→D19-16 (GND)	Input	Voltage	Always	10 to 16 V
D19-10 (IG)←→D19-16 (GND)	Input	Voltage	IG ON	10 to 16 V
D19-11 (ILL+)←→D19-16 (GND)	Input	Voltage	Night illumination ON	10 to 16 V
D19-11 (ILL+)←→D19-16 (GND)	Input	Voltage	Night illumination OFF	Less than 1 V
D19-12 (CANL)←→D19-16 (GND)	Input/Output	Waveform	IG ON	Pulse generation
D19-13 (CANH)←→D19-16 (GND)	Input/Output	Waveform	IG ON	Pulse generation
D19-14 (BLW)←→D19-16 (GND)	Output	Waveform	IG ON Blower switch LO	Pulse generation (waveform 1)
D19-15 (ILL-)←→D19-16 (GND)	Input	-	IG ON Rheostat	10 to 16 V
D19-16 (GND) ←→Chassis ground	-	Resistance	Always	Less than 1 Ω

CONNECTOR D20

Terminal No. (Terminal symbol)	Input/Output	Item	Measuring conditions	Standard value
D20-2 (CLTS) ←→Chassis ground	Input	Voltage	IG ON Put sunlight or light to the sunload sensor.	0.8 to 4.3 V (The voltage varies depending on the light strength.)
D20-29 (S5)←→16 (GND)	Output	Voltage	IG ON	4.75 V to 5.25 V

Waveform 1

Item	Contents
Measuring terminal	F42-22 (BLW) - F42-14 (GND)
Equipment setting	1 V/DIV, 500 μs/DIV
Measuring conditions	IG ON, Blower switch: LO, A/C switch: ON

Fig 2: Waveform 1

Courtesy of SUBARU OF AMERICA, INC.

NOTE: As the blower level is high (increase of air flow), the duty ratio is changed.

Combination meter assembly

Fig 3: Identifying Combination Meter assembly Terminals

Courtesy of SUBARU OF AMERICA, INC.

Standard value

CONNECTOR D7

Terminal No. (Terminal symbol)	Input/Output	Item	Measuring conditions	Standard value
D7-24 (TAM) ←→D7-25 (SG-)	Input	Voltage	IG ON External temperature 25°C (77°F)	1.4 to 1.6 V
D7-24 (TAM) ←→D7-25 (SG-)	Input	Voltage	IG ON External temperature 50°C (122°F)	0.7 to 0.9 V
D7-6 (CANH) ←→Chassis ground	Input/Output	Waveform	IG ON	Pulse generation
D7-7 (CANL) ←→Chassis ground	Input/Output	Waveform	IG ON	Pulse generation

Instrument panel junction block assembly, main body ECM (Network gateway computer)

Fig 4: Identifying Instrument Panel Junction Block assembly, Main Body ECM (Network Gateway Computer)

Courtesy of SUBARU OF AMERICA, INC.

Inspection of instrument panel junction block assembly and main body ECM (network gateway computer)

Remove the main body ECM (network gateway computer) from the instrument panel junction block assembly.
Check the resistance and voltage between the instrument panel junction block assembly connector terminals.

Standard value

CONNECTOR MB

Terminal No. (Terminal symbol)	Input/Output	Item	Measuring conditions	Standard value
MB8 ←→Chassis ground	Input	Voltage	IG ON	11 to 14 V
MB9 ←→Chassis ground	Input	Voltage	IG ACC	11 to 14 V
MB11 ←→Chassis ground	-	Resistance	Always	Less than 1 Ω

NOTE: If it is out of the standard value, it can be judged as malfunction of the vehicle.

Engine control computer

Fig 5: Identifying Engine Control Computer Terminals

Courtesy of SUBARU OF AMERICA, INC.

Standard value

CONNECTOR A33

Terminal No. (Terminal symbol)	Input/Output	Item	Measuring conditions	Standard value
A33-8 (ACP) ←→Chassis ground	Input	Voltage	When refrigerant pressure is normal	0.63 to 4.73 V
A33-18 (CANL) ←→Chassis ground	Input/Output	Waveform	IG ON	Pulse generation
A33-19 (CANH) ←→Chassis ground	Input/Output	Waveform	IG ON	Pulse generation