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A/C Control Module

G13866997Courtesy of SUBARU OF AMERICA, INC.
Terminal No. Contents Measuring condition Standard
(i80) No. 1 (+) ←→ Chassis ground (-) Seat heater (Dr) drive output(1) Ignition switch: ON
Seat heater switch: ON
0 V or battery voltage
(i80) No. 2 (+) ←→ Chassis ground (-) Seat heater (Dr) GND(1) Always Resistance 1 Ω or less
(i80) No. 3 (+) ←→ Chassis ground (-) Seat heater (Pa) drive output(1) Ignition switch: ON
Seat heater switch: ON
0 V or battery voltage
(i80) No. 4 (+) ←→ Chassis ground (-) Seat heater (Pa) GND(1) Always Resistance 1 Ω or less
(i80) No. 5 - - -
(i80) No. 6 - - -
(i80) No. 7 - - -
(i80) No. 8 - - -
(i80) No. 9 - - -
(i80) No. 10 (+) ←→ Chassis ground Blower motor relay drive output Ignition switch: ON
Blower switch: ON
0.7 V or less
(i80) No. 11 - - -
(i80) No. 12 - - -
(i80) No. 13 - - -
(i80) No. 14 - - -
(i80) No. 15 (+) ←→ Chassis ground (-) Rear mode door actuator position signal Ignition switch: ON
Rear mode door: VENT position
4.2 V
Ignition switch: ON
Rear mode door: HEAT position
1.0 V
(i80) No. 16 - - -
(i80) No. 17 (+) ←→ Chassis ground (-) Seat heater (Dr) temperature sensor signal Ignition switch: ON
Varies depending on temperature at seat heater
0 - 5 V
(i80) No. 18 (+) ←→ Chassis ground (-) PTC heater 1 relay drive output In operation 1 V or less
(i80) No. 19 (+) ←→ Chassis ground (-) PTC heater 2 relay drive output In operation 1 V or less
(i80) No. 20 (+) ←→ Chassis ground (-) PTC heater 3 relay drive output In operation 1 V or less
(i80) No. 21 (+) ←→ Chassis ground (-) Rear blower motor relay drive output Ignition switch: ON
Rear blower switch: ON
0.7 V or less
(i80) No. 22 - - -
(i80) No. 23 - - -
(i80) No. 24 - - -
(i80) No. 25 (+) ←→ Chassis ground (-) Seat heater (Pa) temperature sensor signal Ignition switch: ON
Varies depending on temperature at seat heater
0 - 5 V
(i80) No. 26 (+) ←→ Chassis ground (-) Rear air mix door actuator position signal Ignition switch: ON
Rear air mix door: MAX COOL
4.0 V
Ignition switch: ON
Rear air mix door: MAX HOT
1.8 V
(i181) No. 1 - - -
(i181) No. 2 - - -
(i181) No. 3 Body CAN H Digital signal; cannot be measured -
(i181) No. 4 Body CAN L Digital signal; cannot be measured -
(i181) No. 5 - - -
(i181) No. 6 (+) ←→ Chassis ground (-) Rear blower motor control output Ignition switch: ON
Rear airflow capacity: MIN
1 - 5 V
(i181) No. 7 (+) ←→ Chassis ground (-) Pressure sensor signal Ignition switch: ON 0.5 - 4.9 V
(i181) No. 8 (+) ←→ Chassis ground (-) Evaporator sensor signal Ignition switch: ON 1 - 4.5 V (changes depending on evaporator temperature)
(i181) No. 9 (+) ←→ Chassis ground (-) Mode door actuator position signal Ignition switch: ON
Mode door: VENT position
4.5 V
Ignition switch: ON
Mode door: DEF position
0.5 V
(i181) No. 10 (+) ←→ Chassis ground (-) Blower motor control output Ignition switch: ON
Blower switch: ON
0.6 - 6 V
(i181) No. 11 (+) ←→ Chassis ground (-) Rear blower motor voltage feedback signal Ignition switch: ON
Rear airflow capacity: MIN
4.5 V or more
(i181) No. 12 - - -
(i181) No. 13 - - -
(i181) No. 14 - - -
(i181) No. 15 - - -
(i181) No. 16 - - -
(i181) No. 17 - - -
(i181) No. 18 (+) ←→ Chassis ground (-) Rear evaporator sensor signal Ignition switch: ON 1 - 4.5 V (changes depending on evaporator temperature)
(i181) No. 19 (+) ←→ Chassis ground (-) Air mix door actuator (Pa) position signal Ignition switch: ON
Air mix door: MAX COOL
4.5 V
Ignition switch: ON
Air mix door: MAX HOT
0.5 V
(i181) No. 20 (+) ←→ Chassis ground (-) Intake door actuator position signal Ignition switch: ON
FRESH/RECIRC door: RECIRC position
4.5 V
Ignition switch: ON
FRESH/RECIRC door: FRESH position
1.9 V
(i181) No. 21 (+) ←→ Chassis ground (-) Rear in-vehicle sensor signal Ignition switch: ON 25°C (77°F): Approx. 1.5 V
40°C (104°F): Approx. 1.0 V
(i181) No. 22 (+) ←→ Chassis ground (-) Flow sensor signal Ignition switch: ON
Blower switch: ON
A/C switch: ON
0.3 - 4.7 V
(i181) No. 23 (+) ←→ Chassis ground (-) Sunload sensor signal Ignition switch: ON
Sunlight is contacting sensor
With sunload: Less than 4.9 V
Without sunload: 0 V
(i181) No. 24 (+) ←→ Chassis ground (-) In-vehicle sensor signal Ignition switch: ON 25°C (77°F): Approx. 1.5 V
40°C (104°F): Approx. 1.0 V
(i329) No. 1 (+) ←→ Chassis ground (-) GND Always Resistance 1 Ω or less
(i329) No. 2 LIN (communication line) Digital signal; cannot be measured -
(i329) No. 3 - - -
(i329) No. 4 (+) ←→ Chassis ground (-) Variable compressor solenoid valve drive output Ignition switch: ON
Blower switch: ON
A/C switch: ON
2 - 12 V
(i329) No. 5 (+) ←→ Chassis ground (-) Mode door actuator drive output (VENT) While operating to VENT side While operating: 12 V
While not operating: 0 V
(i329) No. 6 (+) ←→ Chassis ground (-) Mode door actuator drive output (DEF) While operating to DEF side While operating: 12 V
While not operating: 0 V
(i329) No. 7 (+) ←→ Chassis ground (-) Air mix door actuator (Dr) drive output (COOL) While operating to COOL side While operating: 12 V
While not operating: 0 V
(i329) No. 8 (+) ←→ Chassis ground (-) Air mix door actuator (Dr) drive output (HOT) While operating to HOT side While operating: 12 V
While not operating: 0 V
(i329) No. 9 (+) ←→ Chassis ground (-) Ignition power supply Ignition switch: ON Battery voltage
(i329) No. 10 (+) ←→ Chassis ground (-) Battery power supply Always Battery voltage
(i329) No. 11 (+) ←→ Chassis ground (-) Air mix door actuator (Dr) position signal Ignition switch: ON
Air mix door: MAX COOL
4.5 V
Ignition switch: ON
Air mix door: MAX HOT
0.5 V
(i329) No. 12 (+) ←→ Chassis ground (-) Sensor and actuator power supply Ignition switch: ON 5 V
(i329) No. 13 - - -
(i329) No. 14 - - -
(i329) No. 15 - - -
(i329) No. 16 (+) ←→ Chassis ground (-) Rear mode door actuator drive output (HEAT) While operating to HEAT side While operating: 12 V
While not operating: 0 V
(i329) No. 17 (+) ←→ Chassis ground (-) Rear mode door actuator drive output (VENT) While operating to VENT side While operating: 12 V
While not operating: 0 V
(i329) No. 18 (+) ←→ Chassis ground (-) Air mix door actuator (Pa) drive output (HOT) While operating to HOT side While operating: 12 V
While not operating: 0 V
(i329) No. 19 (+) ←→ Chassis ground (-) Intake door actuator drive output (RECIRC) While operating to RECIRC side While operating: 12 V
While not operating: 0 V
(i329) No. 20 (+) ←→ Chassis ground (-) Rear air mix door actuator drive output (COOL) While operating to COOL side While operating: 12 V
While not operating: 0 V
(i329) No. 21 - - -
(i329) No. 22 - - -
(i329) No. 23 - - -
(i329) No. 24 (+) ←→ Chassis ground (-) Sensor GND Always Resistance 1 Ω or less
(i329) No. 25 - - -
(i329) No. 26 - - -
(i329) No. 27 (+) ←→ Chassis ground (-) Air mix door actuator (Pa) drive output (COOL) While operating to COOL side While operating: 12 V
While not operating: 0 V
(i329) No. 28 (+) ←→ Chassis ground (-) ACC power supply Ignition switch: ACC Battery voltage
(i329) No. 29 (+) ←→ Chassis ground (-) Intake door actuator drive output (FRESH) While operating to FRESH side While operating: 12 V
While not operating: 0 V
(i329) No. 30 (+) ←→ Chassis ground (-) Rear air mix door actuator drive output (HOT) While operating to HOT side While operating: 12 V
While not operating: 0 V
(1) Model with seat heater and without seat ventilation