Contents Wiring diagrams Section: Automatic HVAC System All sections

HVAC System (Auto AC) (Diagnostics): Wiring Subaru Outback BR

WIRING DIAGRAM

StepCheckYesNo
1 CHECK CURRENT DATA. Using the Subaru Select Monitor, check "In-vehicle Sensor Temperature" of the current data from the A/C diagnosis.Does the current data display 25°C (77°F)?Go to step 2 .Check the connection of the in-vehicle sensor circuit.
2 CHECK IN-VEHICLE SENSOR. Disconnect the in-vehicle sensor. Short the i173 connector. Using the Subaru Select Monitor, check "In-vehicle Sensor Temperature" of the current data from the A/C diagnosis.Does the current data display 25°C (77°F)?Go to step 3 .Replace the in-vehicle sensor. Ref. to REMOVAL , In-Vehicle Sensor (Auto A/C Model).
3 CHECK HARNESS. Turn the ignition switch to ON. Using the tester, measure the voltage between terminals. Connector & terminal (i173) No. 1 - No. 2Is the voltage 4.5 - 5.0 V?Go to step 4 .Repair or replace the open circuit of harness.
4 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (i173) No. 1 - (i81) No. 1: (i173) No. 2 - (i80) No. 11Is there continuity?Replace the A/C CM. Ref. to REMOVAL , Control Unit.Repair or replace the open circuit of harness.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Using the Subaru Select Monitor, check "Evaporator Temperature" of the current data from the A/C diagnosis.Is the current data lower than -30°C (-54°F)?Go to step 2 .Check the connection of the evaporator sensor circuit.
2 CHECK EVAPORATOR SENSOR. Disconnect the evaporator sensor. Short the i172 connector. Using the Subaru Select Monitor, check "Evaporator Temperature" of the current data from the A/C diagnosis.Is the current data lower than -30°C (-54°F)?Go to step 3 .Replace the evaporator sensor. Ref. to REMOVAL , Evaporator.
3 CHECK HARNESS. Turn the ignition switch to ON. Using the tester, measure the voltage between terminals. Connector & terminal (i172) No. 1 - No. 2Is the voltage 4.5 - 5.0 V?Check the connection of the evaporator sensor circuit.Go to step 4 .
4 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (i172) No. 1 - (i80) No. 21: (i172) No. 2 - (i81) No. 1Is there continuity?Replace the A/C CM. Ref. to REMOVAL , Control Unit.Repair or replace the open circuit of harness.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Using the Subaru Select Monitor, check "Refrigerant Pressure" of the current data from the A/C diagnosis.Does the current data display 0 MPa?Go to step 2 .Check the connection of the refrigerant pressure sensor.
2 CHECK REFRIGERANT PRESSURE SENSOR. Disconnect the refrigerant pressure sensor. Using the Subaru Select Monitor, check "Refrigerant Pressure" of the current data from the A/C diagnosis.Does the current data display 0 MPa?Go to step 3 .Replace the refrigerant pressure sensor. Ref. to REMOVAL , Evaporator.
3 CHECK HARNESS. Turn the ignition switch to ON. Using the tester, measure the voltage between terminals. Connector & terminal (B505) No. 1 - No. 3Is the voltage 4.5 - 5.0 V?Go to step 4 .Repair or replace the open circuit of harness.
4 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (B505) No. 1 - No. 2: (B505) No. 2 - No. 3: (B505) No. 3 - No. 1Is there continuity?Repair or replace the short circuit of the harness.Replace the A/C CM. Ref. to REMOVAL , Control Unit.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Using the Subaru Select Monitor, check "Quantity of Sunload" of the current data from the A/C diagnosis.Does the current data display 0 W/m 2 ?Go to step 2 .Check the connection of the sunload sensor circuit.
2 CHECK SUNLOAD SENSOR. Disconnect the sunload sensor. Short the i51 connector. Using the Subaru Select Monitor, check "Quantity of Sunload" of the current data from the A/C diagnosis.Does the current data display 0 W/m 2 ?Go to step 3 .Replace the sunload sensor. Ref. to REMOVAL , Evaporator.
3 CHECK HARNESS. Turn the ignition switch to ON. Using the tester, measure the voltage between terminals. Connector & terminal (i51) No. 1 - No. 2Is the voltage 4.5 - 5.0 V?Check the connection of the sunload sensor circuit.Go to step 4 .
4 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (i51) No. 1 - (i80) No. 16: (i51) No. 2 - (i81) No. 23Is there continuity?Replace the A/C CM. Ref. to REMOVAL , Control Unit.Repair or replace the open circuit of harness.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CONNECTOR. Check the condition of connector connection. Read the DTC of the A/C CM using the Subaru Select Monitor.Is B1611 displayed?Go to step 2 .Repair the poor contact of connector.
2 CHECK ACTUATOR. Disconnect the air mix door actuator (driver's). Read the DTC of the A/C CM using the Subaru Select Monitor.Is B1610 displayed?Replace the air mix door actuator (driver's).Go to step 3 .
3 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (i174) No. 1 - (i174) No. 3: (i174) No. 3 - (i174) No. 5: (i174) No. 5 - (i174) No. 1Is there continuity?Repair or replace the short circuit of the harness.Go to step 4 .
4 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (i174) No. 1 - (i80) No. 16: (i174) No. 3 - (i181) No. 1: (i174) No. 5 - (i80) No. 14Is there continuity?Replace the A/C CM. Ref. to REMOVAL , Control Unit.Repair or replace the short circuit of the harness.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CONNECTOR. Check the condition of connector connection. Read the DTC of the A/C CM using the Subaru Select Monitor.Is B1612 displayed?Go to step 2 .Repair the poor contact of connector.
2 CHECK CURRENT DATA. Using the Subaru Select Monitor, change the setting of "Airmix Dr Act Trgt Open Angle (Driver's)" from the A/C diagnosis and perform the active test.Did the actuator move to the specified target opening angle?Air mix door actuator circuit is normal.Go to step 3 .
3 CHECK AIR MIX DOOR ACTUATOR - POTENTIOMETER. Using the temperature control button, change the set temperature. Using the Subaru Select Monitor, check "Airmix Door Actuator Position (Driver's)" of the current data from the A/C diagnosis.Does the current data change?Go to step 4 .Replace the air mix door actuator (driver's). Ref. to REMOVAL , Heater and Cooling Unit.
4 CHECK HARNESS. Turn the ignition switch to ON. Using the tester, measure the voltage between terminals. Connector & terminal (i174) No. 1 - No. 3Is the voltage 4.5 - 5.0 V?Check the connection of the air mix door actuator position circuit.Go to step 5 .
5 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (i174) No. 5 - (i80) No. 14Is there continuity?Replace the A/C CM. Ref. to REMOVAL , Control Unit.Repair or replace the open circuit of harness.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CONNECTOR. Check the condition of connector connection. Read the DTC of the A/C CM using the Subaru Select Monitor.Is B1614 displayed?Go to step 2 .Repair the poor contact of connector.
2 CHECK ACTUATOR. Disconnect the air mix door actuator. Read the DTC of the A/C CM using the Subaru Select Monitor.Is B1614 displayed?Go to step 3 .Replace the air mix door actuator position (passenger's).
3 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (i175) No. 1 - (i175) No. 3: (i175) No. 3 - (i175) No. 5: (i175) No. 5 - (i175) No. 1Is there continuity?Repair or replace the short circuit of the harness.Go to step 4 .
4 CHECK HARNESS. Using a tester, check continuity between terminals. Connector & terminal (i175) No. 1 - (i181) No. 1: (i175) No. 3 - (i80) No. 16: (i175) No. 5 - (i80) No. 25Is there continuity?Replace the A/C CM. Ref. to REMOVAL , Control Unit.Repair or replace the short circuit of the harness.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CONNECTOR. Check the condition of connector connection. Read the DTC of the A/C CM using the Subaru Select Monitor.Is B1615 displayed?Go to step 2 .Repair the poor contact of connector.
2 CHECK CURRENT DATA. Using the Subaru Select Monitor, change the setting of "Airmix Dr Act Trgt Open Angle (Pas's)" from the A/C diagnosis and perform the active test.Did the actuator move to the specified target opening angle?Air mix door actuator circuit is normal.Go to step 3 .
3 CHECK AIR MIX DOOR ACTUATOR - POTENTIOMETER. Using the temperature control button, change the set temperature. Using the Subaru Select Monitor, check "Airmix Door Actuator Position (Passenger's)" of the current data from the A/C diagnosis.Does the current data change?Go to step 4 .Replace the air mix door actuator (passenger's). Ref. to REMOVAL , Heater and Cooling Unit.
4 CHECK HARNESS. Turn the ignition switch to ON. Using the tester, measure the voltage between terminals. Connector & terminal (i175) No. 1 - No. 3Is the voltage 4.5 - 5.0 V?Check the connection of the air mix door actuator position circuit.Go to step 5 .
5 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (i175) No. 5 - (i181) No. 25Is there continuity?Replace the A/C CM. Ref. to REMOVAL , Control Unit.Repair or replace the open circuit of harness.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CONNECTOR. Check the condition of connector connection. Read the DTC of the A/C CM using the Subaru Select Monitor.Is B1621 displayed?Go to step 2 .Repair the poor contact of connector.
2 CHECK ACTUATOR. Disconnect the mode door actuator. Read the DTC of the A/C CM using the Subaru Select Monitor.Is B1620 displayed?Go to step 3 .Replace the mode door actuator. Ref. to REMOVAL , Heater and Cooling Unit.
3 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (i176) No. 1 - (i176) No. 2: (i176) No. 2 - (i176) No. 3: (i176) No. 3 - (i176) No. 1Is there continuity?Repair or replace the short circuit of the harness.Go to step 4 .
4 CHECK HARNESS. Using a tester, check continuity between terminals. Connector & terminal (i176) No. 1 - (i80) No. 16: (i176) No. 2 - (i181) No. 1: (i176) No. 3 - (i80) No. 26Is there continuity?Replace the A/C CM. Ref. to REMOVAL , Control Unit.Repair or replace the open circuit of harness.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CONNECTOR. Check the condition of connector connection. Read the DTC of the A/C CM using the Subaru Select Monitor.Is B1622 displayed?Go to step 2 .Repair the poor contact of connector.
2 CHECK CURRENT DATA. Using the Subaru Select Monitor, change the setting of "Mode Door Actuator Position Target" from the A/C diagnosis and perform the active test.Did the actuator move to the specified target opening angle?Mode door actuator circuit is normal.Go to step 3 .
3 CHECK MODE DOOR ACTUATOR - POTENTIOMETER. Using the temperature control button, change the set temperature. Using the Subaru Select Monitor, check "Mode Door Actuator Position" of the current data from the A/C diagnosis.Does the current data change?Go to step 4 .Replace the mode door actuator (passenger's). Ref. to REMOVAL , Heater and Cooling Unit.
4 CHECK HARNESS. Turn the ignition switch to ON. Using the tester, measure the voltage between terminals. Connector & terminal (i176) No. 1 - No. 2Is the voltage 4.5 - 5.0 V?Check the connection of the mode door actuator position circuit.Go to step 5 .
5 CHECK HARNESS. Disconnect the connector from A/C CM. Using a tester, check continuity between terminals. Connector & terminal (i176) No. 3 - (i80) No. 26Is there continuity?Replace the A/C CM. Ref. to REMOVAL , Control unit.Repair or replace the open circuit of harness.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK CURRENT DATA. Using the Subaru Select Monitor, check "Refrigerant Flow".Is the value 3.2 MPa or more?Go to step 2 .Refrigerate flow sensor circuit is normal.
2 CHECK SENSOR POWER SUPPLY. Disconnect the refrigerant flow sensor connector. Turn the ignition switch to ON. Using the tester, measure the voltage between terminals. Connector & terminal (B507) No. 1 - No. 2Is the voltage 4.5 - 5.0 V?Go to step 6 .Go to step 3 .
3 CHECK HARNESS. Disconnect the A/C CM connector. Using a tester, check continuity between terminals. Connector & terminal (B507) No. 3 - (i80) No. 13: (B507) No. 2 - (i181) No. 1: (B507) No. 1 - (i80) No. 16Is there continuity?Go to step 4 .Repair or replace the open circuit of harness.
4 CHECK HARNESS. Using a tester, check continuity between terminals. Connector & terminal (B507) No. 1 - Chassis ground: (B507) No. 2 - Chassis ground: (B507) No. 3 - Chassis groundIs there continuity?Repair or replace the short circuit of the harness.Go to step 5 .
5 CHECK HARNESS. Using a tester, check continuity between terminals. Connector & terminal (B507) No. 1 - No. 2: (B507) No. 1 - No. 3: (B507) No. 2 - No. 3Is there continuity?Repair or replace the short circuit of the harness.Go to step 6 .
6 CHECK A/C CM. Replace the A/C CM with a normal part. Read the DTC using Subaru Select Monitor.Is B1641 detected?Replace refrigerant flow sensor.Replace the A/C CM. Ref. to REMOVAL , Control Unit.

DIAGNOSTIC PROCEDURE

StepCheckYesNo
1 CHECK AMOUNT OF REFRIGERANT. Check the refrigerant pressure and filling amount. Ref. to PROCEDURE , Refrigerant Pressure with Manifold Gauge Set.Is the filling amount a standard value?Check the refrigerant pressure sensor or refrigerant flow sensor for defect.Replace the compressor.

DIAGNOSTIC PROCEDURE