PROCEDURE
Note. When the sunload sensor check is performed indoors or in the shade, it could be diagnosed as sensor having an open circuit. Always perform the inspection in direct sunlight.
| Step | Check | Yes | No |
|---|---|---|---|
| 1 START INSPECTIONS. Prepare the tools. Refer to PREPARATION TOOL . Perform the pre-inspection. Refer to INSPECTION . | Is any malfunction found in pre-inspection? | Fix the malfunction found in pre-inspection, and go to the next inspection step. Go to step 2 . | Go to step 2 . |
| 2 PREPARE SUBARU SELECT MONITOR. Prepare the Subaru Select Monitor. | Is the Subaru Select Monitor ready? | Go to step 3 . | Go to step 4 . |
| 3 CHECK DTC. Under the failure condition, leave the vehicle for one minute or more. Read the DTC using Subaru Select Monitor. NOTE: If the communication function of the Subaru Select Monitor cannot be executed properly, check the communication circuit. Refer to COMMUNICATION FOR INITIALIZING IMPOSSIBLE . Record the freeze frame data recorded together with the DTC. | Is DTC displayed? | Refer to LIST . | Refer to Diagnostics with Phenomenon. Refer to INSPECTION . |
| 4 A/C CONTROL PANEL SELF-DIAGNOSIS. Under the failure condition, leave the vehicle for one minute or more. Perform the self-diagnosis of A/C control panel. Refer to OPERATION . | Are other codes except "20" displayed? | Refer to SENSOR CHECK TABLE . | Refer to Diagnostics with Phenomenon. Refer to INSPECTION . |
| NOTE |
|---|
| If the communication function of the Subaru Select Monitor cannot be executed properly, check the communication circuit. Refer to COMMUNICATION FOR INITIALIZING IMPOSSIBLE . Record the freeze frame data recorded together with the DTC. |
CAUTION
- Never connect the battery in reverse polarity. Doing so may immediately damage the A/C CM.
- Do not disconnect the battery terminals while the engine is running. A large counter electromotive force will be generated in the generator, and this voltage may damage electronic parts such as A/C CM etc.
- Before disconnecting the connectors of sensors and the A/C CM, be sure to turn off the ignition switch. A/C CM may be damaged.
- Every A/C-related part is a precision part. Do not drop them.
- Airbag system wiring harness is routed near the A/C control panel and junction box. CAUTION: Do not use electrical test equipment on the airbag system wiring harness and connector. Be careful not to damage the airbag system wiring harness when servicing the A/C control panel and junction box.
BATTERY
Check the battery. Refer to INSPECTION (H4DO) or INSPECTION (H6DO).
Note. If the battery voltage does not reach the specified value, recharge or replace the battery.
GENERAL TOOL
| TOOL NAME | REMARKS |
|---|---|
| Circuit tester | Used for measuring resistance, voltage and current. |
Scheme 64
Scheme 65
Scheme 66
| Terminal No. | Description | Measuring condition | Standard |
|---|---|---|---|
| A1 | Battery power supply | Always | Battery voltage |
| A2 | Ignition power supply | Ignition switch: ON | Battery voltage |
| A3 | ACC power supply | Ignition switch: ACC | Battery voltage |
| A4 | CAN communication (Hi) | Digital signal; can not be measured | (1) |
| A5 | CAN communication (Lo) | Digital signal; can not be measured | (1) |
| A6 | Ground | Always | 0V |
| A7 | A/C control panel communication | Digital signal; can not be measured | (1) |
| A11 | In-vehicle sensor | Ignition switch: ON | 25°C: Approx. 1.5 V 40°C: Approx. 1.0 V |
| A13 | Flow sensor | Ignition switch: ON | 0.3 - 4.7 V |
| A14 | Air mix door position signal (2) or air mix door (driver's seat) position signal (3) | Ignition switch: ON, Air mix door: maximum cool position | 4 V |
| Ignition switch: ON, Air mix door: maximum hot position | 1 V | ||
| A16 | Each potentiometer and sensor power supply | Ignition switch: ON | 5 V |
| A17 | Rear vent actuator position signal (4) | Ignition switch: ON, Air mix door: maximum cool position | 1.8 V |
| Ignition switch: ON, Air mix door: maximum hot position | 4.1 V | ||
| A18 | A/C control panel communication | Digital signal; can not be | Measured (1) |
| A21 | After-evaporator sensor signal | Ignition switch: ON, fluctuates depending on temperature after the evaporator. | 1 - 4.5 V |
| A22 | Pressure sensor | Ignition switch: ON | 0.5 - 4.9 V |
| A24 | Sunload sensor (with automatic light) (3) | Ignition switch: ON (0 V: No sunload) | 0 - 4.9 V |
| A25 | Air mix door actuator (passenger's seat) position signal (3) | Ignition switch: ON, Air mix door: maximum cool position | 4 V |
| Ignition switch: ON, Air mix door: maximum hot position | 1 V | ||
| A26 | Mode door actuator position signal | Ignition switch: ON, Mode door: FACE position | 4 V |
| Ignition switch: ON, Mode door: DEF position | 1 V | ||
| B1 | Sensor GND | Always | Less than 0.5 V |
| B2 | Variable compressor solenoid valve | Ignition switch: ON, Blower switch: ON, A/C switch: ON | 2 - 12 V |
| B3 | Intake door actuator drive signal (FRESH) | Intake door actuator operating on the FRESH side | 0.7 V or less |
| B4 | Air mix door actuator (passenger's seat) drive signal (HOT) (3) | Turning towards HOT side: B4 is 12 V, B16 is GND | While operating: 12 V While not operating: 0 V |
| B16 | Air mix door actuator (passenger's seat) drive signal (COOL) (3) | Turning towards COOL side: B16 is 12 V, B4 is GND | |
| B6 | Intake door actuator drive signal (RECIRC) | Intake door actuator operating on the RECIRC side | 0.7 V or less |
| B8 | Blower motor voltage feedback (3) | Ignition switch: ON, Blower switch: ON | 0.45 - 10 V |
| B9 | Blower motor control signal (3) | Ignition switch: ON, Blower switch: ON | 9.05 V |
| B11 | Mode servo drive signal (FACE) | When turning towards FACE side: B11 is 12 V, B13 is GND | While operating: 12 V While not operating: 0 V |
| B13 | Mode servo drive signal (DEF) | When turning towards DEF side: B13 is 12 V, B11 is GND | |
| B20 | Heater main relay drive signal (3) | Ignition switch: ON, Blower switch: ON | 0.7 V or less |
| B21 | Air mix door actuator drive signal (COOL) (2) or air mix door actuator (driver's seat) drive signal (COOL) (3) | Turning towards COOL side: B21 is 12 V, B22 is GND | While operating: 12 V While not operating: 0 V |
| B22 | Air mix door actuator drive signal (HOT) (2) or air mix door actuator (driver's seat) drive signal (HOT) (3) | Turning towards HOT side: B22 is 12 V, B21 is GND | |
| B23 | Rear vent actuator drive signal (HOT) (4) | Turning towards HOT side: B23 is 12 V, B24 is GND | While operating: 12 V While not operating: 0 V |
| B24 | Rear vent actuator drive signal (COOL) (4) | Turning towards COOL side: B24 is 12 V, B23 is GND | |
| (1) Battery voltage cannot be measured because of digital signal. (2) Manual A/C (3) Auto A/C (4) With rear seat A/C | |||
| (1) | Battery voltage cannot be measured because of digital signal. |
| (2) | Manual A/C |
| (3) | Auto A/C |
| (4) | With rear seat A/C |
SENSOR CHECK TABLE
Note. When the sunload sensor check is performed indoors or in the shade, it could be diagnosed as having an open circuit. Always check the sunload sensor with the sun shining on it. When currently malfunctioning, AUTO flashes on display. Past malfunction can be cleared by disconnecting the battery ground cable.
| Display screen | Sensor | Trouble contents | Note |
|---|---|---|---|
| 21 | Open circuit in in-vehicle sensor | In-vehicle air temperature sensor circuit is open. | Refer to DTC B1602 IN-VEHICLE SENSOR OPEN . |
| 21 | Short-circuit in in-vehicle sensor | In-vehicle air temperature sensor circuit is shorted. | Refer to DTC B1601 IN-VEHICLE SENSOR SHORT . |
| 22 | Ambient sensor trouble or communication failure | Sensor trouble or communication failure | Refer to DTC B1635 OUT SIDE TEMPERATURE SENSOR CIRCUIT ABNORMALITY (AIR CONDITIONER) . |
| 23 | Open circuit in evaporator sensor | Post evaporator sensor circuit is open. | Refer to DTC B1604 EVAPORATOR SENSOR OPEN . |
| 23 | Short-circuit in evaporator sensor | Post evaporator sensor circuit is shorted. | Refer to DTC B1603 EVAPORATOR SENSOR SHORT . |
| 24 | Engine coolant temperature sensor trouble or communication failure | Sensor trouble or communication failure | |
| 25 | Open circuit in sunload sensor | Sunload sensor circuit is open. (1) | Refer to DTC B1608 SUNLOAD SENSOR OPEN . |
| 25 | Short-circuit in sunload sensor | Sunload sensor circuit is shorted. | Refer to DTC B1607 SUNLOAD SENSOR SHORT . |
| 26 | Open circuit in air mix door actuator - potentiometer (driver's) | Air mix door actuator potentiometer circuit is open. | Refer to DTC B1610 AIRMIX DOOR ACTUATOR POTENTIOMETER CIRCUIT OPEN (DRIVER'S) . |
| 26 | Open circuit in air mix door actuator - potentiometer (passenger's) | Air mix door actuator potentiometer circuit is open. | Refer to DTC B1613 AIRMIX DOOR ACTUATOR POTENTIOMETER CIRCUIT OPEN (PASSENGER'S) . |
| 27 | Short-circuit in air mix door actuator - potentiometer (driver's) | Air mix door actuator potentiometer circuit is shorted. | Refer to DTC B1611 AIRMIX DOOR ACTUATOR POTENTIOMETER CIRCUIT SHORT (DRIVER'S) . |
| 27 | Short-circuit in air mix door actuator - potentiometer (passenger's) | Air mix door actuator potentiometer circuit is shorted. | Refer to DTC B1614 AIRMIX DOOR ACTUATOR POTENTIOMETER CIRCUIT SHORT (PASSENGER'S) . |
| 28 | Open circuit in mode door actuator - potentiometer | Mode door actuator potentiometer circuit is open. | Refer to DTC B1620 MODE DOOR ACTUATOR POTENTIOMETER CIRCUIT OPEN . |
| 29 | Short-circuit in mode door actuator - potentiometer | Mode door actuator potentiometer circuit is shorted. | Refer to DTC B1621 MODE DOOR ACTUATOR POTENTIOMETER CIRCUIT SHORT . |
| 41 | Open circuit in rear vent door actuator - potentiometer (2) | Rear vent door actuator potentiometer circuit is open. | Refer to DTC B1630 REAR VENT DOOR ACTUATOR POTENTIOMETER CIRCUIT OPEN . |
| 41 | Short-circuit in rear vent door actuator-potentiometer (2) | Rear vent door actuator potentiometer circuit is shorted. | Refer to DTC B1631 REAR VENT DOOR ACTUATOR POTENTIOMETER CIRCUIT SHORT . |
| 42 | Open circuit in refrigerant pressure sensor | Pressure sensor circuit is open. (1) | Refer to DTC B1605 REFRIGERANT FLOW SENSOR CIRCUIT OPEN . |
| 42 | Short-circuit in refrigerant pressure sensor | Pressure sensor circuit is shorted. (1) | Refer to DTC B1606 REFRIGERANT FLOW SENSOR CIRCUIT SHORT . |
| 43 | Open circuit in refrigerant flow sensor | Refrigerant flow circuit is open. (1) | Refer to DTC B1642 REFRIGERANT FLOW SENSOR CIRCUIT OPEN . |
| 43 | Short-circuit in refrigerant flow sensor | Refrigerant flow sensor circuit is shorted. (1) | Refer to DTC B1641 REFRIGERANT FLOW SENSOR CIRCUIT SHORT . |
| 44 | Refrigerant flow sensor circuit failure | Refrigerant flow sensor is faulty. | |
| 45 | Open circuit in sunload sensor (auto light control) | Sunload sensor circuit is open. | Refer to DTC B1608 SUNLOAD SENSOR OPEN . |
| 45 | Short-circuit in sunload sensor (auto light control) | Sunload sensor circuit is shorted. (1) | Refer to DTC B1607 SUNLOAD SENSOR SHORT . |
| 46 | Variable flow change solenoid duty circuit failure | Variable flow change solenoid duty circuit is open or shorted. (1) | Refer to DTC B1643 VARIABLE FLOW CHANGE SOLENOID DUTY CIRCUIT ABNORMAL . |
| 47 | Air mix door actuator - lock (driver's) | Air mix door actuator does not operate due to being stuck or other reasons. | Refer to DTC B1612 AIRMIX DOOR ACTUATOR LOCK (DRIVER'S) . |
| 48 | Air mix door actuator - lock (passenger's) | Air mix door actuator does not operate due to being stuck or other reasons. | Refer to DTC B1615 AIRMIX DOOR ACTUATOR LOCK (PASSENGER'S) . |
| 49 | Mode door actuator - lock | Mode door actuator does not operate due to being stuck or other reasons. | Refer to DTC B1622 MODE DOOR ACTUATOR LOCK . |
| 53 | Heater control panel communication failure | Communication with heater control panel is impossible. (1) | Refer to DTC U0028 HEATER CONTROL PANEL COMMUNICATION ERROR . |
| 54 | CAN communication bus off | Bus off (1) | Refer to DTC U0001 CAN COMMUNICATION BUS OFF . |
| 55 | CAN communication error | Communication error (1) | Refer to DTC U0002 CAN COMMUNICATION ERROR . |
| 20 blinking | When all conditions are normal | ||
| (1) Displays current malfunction only. (2) Displays for vehicles with rear seat air conditioning only. | |||
| (1) | Displays current malfunction only. |
| (2) | Displays for vehicles with rear seat air conditioning only. |
OPERATING MODE TABLE
| Display screen | Blower fan | Mode door | FRESH/RECIRC door | A/C compressor | Air mix door |
|---|---|---|---|---|---|
| 31 | LO | FACE | FRESH | OFF | Maximum cool |
| 32 | LO | FACE | RECIRC | ON | Maximum cool |
| 33 | M1 | FACE | RECIRC | ON | Maximum cool |
| 34 | M1 | B/L | FRESH | ON | 50% |
| 35 | M1 | FOOT | FRESH | ON | 50% |
| 36 | M3 | FOOT | FRESH | ON | Maximum hot |
| 37 | M3 | F/D | FRESH | ON | Maximum hot |
| 38 | HI | DEF | FRESH | ON | Maximum hot |
LIST
| Items to be displayed | Unit of measure | Remarks | Note |
|---|---|---|---|
| Engine Speed | Rpm | Data value received by CAN | |
| Heater Control Panel Setting Value (Driver's) | LO: 18°C (64°F) HI: 32°C (90°F) | Control panel display value | Auto A/C |
| Heater Control Panel Setting Value (Passenger's) | LO: 18°C (64°F) HI: 32°C (90°F) | Control panel display value | Auto A/C |
| Blower outlet Door Request Temperature | °C (°F) | A/C CM internal setting value | Auto A/C |
| Blower outlet request temperature (Driver's) | °C (°F) | A/C CM internal setting value | Auto A/C |
| Blower outlet request temperature (Passenger's) | °C (°F) | A/C CM internal setting value | Auto A/C |
| Blower Fan Operating Condition | MANU/AUTO | A/C CM input value | Auto A/C |
| A/C Operating Condition | MANU/AUTO | A/C CM input value | Auto A/C |
| Fresh/Recircle Air Operating Condition | MANU/AUTO | A/C CM input value | Auto A/C |
| Mode Operating Condition | MANU/AUTO | A/C CM input value | Auto A/C |
| Rear Defogger | ON/OFF | A/C CM input value | |
| In-vehicle Sensor Temperature | °C (°F) | A/C CM input value | Auto A/C |
| Evaporator Temperature | °C (°F) | A/C CM input value | |
| Quantity of Sunload | W/m 2 | A/C CM input value | Auto A/C |
| Refrigerant Pressure | MPa | A/C CM input value | |
| Refrigerant Flow | Kg/h | A/C CM input value | |
| Air mix door actuator position (driver's side) | % | A/C CM input value | |
| Air mix door actuator position (passenger's side) | % | A/C CM input value | Auto A/C |
| Fresh/Recircle Air Door Actuator Position | % | A/C CM input value | |
| Mode Door Actuator Position | % | A/C CM input value | |
| Heater Water Temperature | °C (°F) | Data value received by CAN | |
| Ambient Air Temperature | °C (°F) | Data value received by CAN | |
| Vehicle Speed | Km/h | Data value received by CAN | |
| Accel. Opening Angle | % | Data value received by CAN | |
| Target air mix door actuator position (driver's side) | % | A/C CM input value | |
| Target air mix door actuator position (passenger's side) | % | A/C CM input value | Auto A/C |
| Fresh/Recircle Air Door Actuator Position Target | % | A/C CM input value | |
| Mode Door Actuator Position Target | % | A/C CM input value | |
| Blower Fan Level | Level | A/C CM output value | Auto A/C |
| Compressor operating conditions (CAN transmission signal) | ON/OFF | CAN transmitted data value | Auto A/C |
| Variable Flow Change Solenoid Duty | % | A/C CM output value | |
| Evaporator Temperature Target | °C (°F) | A/C CM input value | |
| Variable Load Compressor Torque Value | Nm | A/C CM input value | |
| Request idle engine speed | Rpm | A/C CM output value | |
| Request engine speed | 0: Without Request 1: Cooler H 2: Heater H 3: Cooler L 4: Heater L | A/C CM output value | |
| Discharge pressure | MPa | A/C CM input value | |
| Intake pressure | MPa | A/C CM input value | |
| Cooler request distinction | Without Request/With Request | A/C CM output value | |
| Heater request distinction | Without Request/With Request | A/C CM output value |
Note. For detailed operation procedures, refer to "PC application help for Subaru Select Monitor".
Note. When the sunload sensor check is performed indoors or in the shade, it could be diagnosed as having an open circuit. Always check the sunload sensor in direct sunlight.
| DTC | Item | Content of diagnosis | Note |
|---|---|---|---|
| B1601 | In-Vehicle Sensor Short | In-vehicle air temperature sensor circuit is shorted. | Refer to DTC B1601 IN-VEHICLE SENSOR SHORT . |
| B1602 | In-Vehicle Sensor Open | In-vehicle air temperature sensor circuit is open. | Refer to DTC B1602 IN-VEHICLE SENSOR OPEN . |
| B1603 | Evaporator Sensor Short | Post evaporator sensor circuit is shorted. | Refer to DTC B1603 EVAPORATOR SENSOR SHORT . |
| B1604 | Evaporator Sensor Open | Post evaporator sensor circuit is open. | Refer to DTC B1604 EVAPORATOR SENSOR OPEN . |
| B1605 | Refrigerant Flow Sensor Circuit Open | Pressure sensor circuit is open. | (2) Refer to DTC B1605 REFRIGERANT FLOW SENSOR CIRCUIT OPEN . |
| B1606 | Refrigerant Flow Sensor Circuit Short | Pressure sensor circuit is shorted. | (2) Refer to DTC B1606 REFRIGERANT FLOW SENSOR CIRCUIT SHORT . |
| B1607 | Sunload Sensor | Short Sunload sensor circuit is shorted. | (1) Refer to DTC B1607 SUNLOAD SENSOR SHORT . |
| B1608 | Sunload Sensor Open | Sunload sensor circuit is open. | (1) , (2) Refer to DTC B1608 SUNLOAD SENSOR OPEN . |
| B1610 | Airmix Door Actuator Potentiometer Circuit Open (Driver's) | Airmix door actuator potentiometer circuit is open. | Refer to DTC B1610 AIRMIX DOOR ACTUATOR POTENTIOMETER CIRCUIT OPEN (DRIVER'S) . |
| B1611 | Airmix Door Actuator Potentiometer Circuit Short (Driver's) | Airmix door actuator potentiometer circuit is shorted. | Refer to DTC B1611 AIRMIX DOOR ACTUATOR POTENTIOMETER CIRCUIT SHORT (DRIVER'S) . |
| B1612 | Airmix Door Actuator Lock (Driver's) | Mode door actuator is locked. | Refer to DTC B1612 AIRMIX DOOR ACTUATOR LOCK (DRIVER'S) . |
| B1613 | Airmix Door Actuator Potentiometer Circuit Open (Passenger's) | Airmix door actuator potentiometer circuit is open. | Refer to DTC B1613 AIRMIX DOOR ACTUATOR POTENTIOMETER CIRCUIT OPEN (PASSENGER'S) . |
| B1614 | Airmix Door Actuator Potentiometer Circuit Short (Passenger's) | Airmix door actuator potentiometer circuit is shorted. | Refer to DTC B1614 AIRMIX DOOR ACTUATOR POTENTIOMETER CIRCUIT SHORT (PASSENGER'S) . |
| B1615 | Airmix Door Actuator Lock (Passenger's) | Mode door actuator is locked. | Refer to DTC B1615 AIRMIX DOOR ACTUATOR LOCK (PASSENGER'S) . |
| B1620 | Mode Door Actuator Potentiometer Circuit Open | Mode door actuator potentiometer circuit is open. | Refer to DTC B1620 MODE DOOR ACTUATOR POTENTIOMETER CIRCUIT OPEN . |
| B1621 | Mode Door Actuator Potentiometer Circuit Short | Mode door actuator potentiometer circuit is shorted. | Refer to DTC B1621 MODE DOOR ACTUATOR POTENTIOMETER CIRCUIT SHORT . |
| B1622 | Mode Door Actuator Lock | Mode door actuator is locked. | Refer to DTC B1622 MODE DOOR ACTUATOR LOCK . |
| B1630 | Rear Vent Door Actuator Potentiometer Circuit Open | Rear vent door actuator potentiometer circuit is open. | Refer to DTC B1630 REAR VENT DOOR ACTUATOR POTENTIOMETER CIRCUIT OPEN . |
| B1631 | Rear Vent Door Actuator Potentiometer Circuit Short | Rear vent door actuator potentiometer circuit is shorted. | Refer to DTC B1631 REAR VENT DOOR ACTUATOR POTENTIOMETER CIRCUIT SHORT . |
| B1632 | Rear Vent Door Actuator Lock | Rear vent door actuator is locked. | Refer to DTC B1632 REAR VENT DOOR ACTUATOR LOCK . |
| B1635 | Out Side Temperature Sensor Circuit Abnormality (Air Conditioner) | Ambient air temperature sensor circuit is abnormal. | Refer to DTC B1635 OUT SIDE TEMPERATURE SENSOR CIRCUIT ABNORMALITY (AIR CONDITIONER) . |
| B1641 | Refrigerant Flow Sensor Circuit Short | Refrigerant flow sensor circuit is shorted. | (2) Refer to DTC B1641 REFRIGERANT FLOW SENSOR CIRCUIT SHORT . |
| B1642 | Refrigerant Flow Sensor Circuit Open | Refrigerant flow sensor circuit is open. | (2) Refer to DTC B1642 REFRIGERANT FLOW SENSOR CIRCUIT OPEN . |
| B1643 | Variable Flow Change Solenoid Duty Circuit Abnormal | Variable flow change solenoid duty circuit is open or shorted. | (2) Refer to DTC B1643 VARIABLE FLOW CHANGE SOLENOID DUTY CIRCUIT ABNORMAL . |
| B1644 | Refrigerant Not Sealed Drive Error | Compressor is rotated before filling refrigerant. | Displays when delivery mode only. Refer to DTC B1644 REFRIGERANT NOT SEALED DRIVE ERROR . |
| U0001 | CAN Communication Bus Off | CAN communication bus off | (2) Refer to DTC U0001 CAN COMMUNICATION BUS OFF . |
| U0002 | CAN Communication Error | CAN communication error | (2) Refer to DTC U0002 CAN COMMUNICATION ERROR . |
| U0028 | Heater Control Panel Communication Error | Communication with heater control panel is faulty. | (2) Refer to DTC U0028 HEATER CONTROL PANEL COMMUNICATION ERROR . |
| (1) When the sunload sensor inspection is performed indoors or in the shade, it may be diagnosed as having an open circuit due to an insufficient light volume. In this case, check the sunload sensor at a location exposed to direct sunlight. (2) Displays current malfunction only. | |||
| (1) | When the sunload sensor inspection is performed indoors or in the shade, it may be diagnosed as having an open circuit due to an insufficient light volume. In this case, check the sunload sensor at a location exposed to direct sunlight. |
| (2) | Displays current malfunction only. |