Cold Air Does Not Come Out Even When The A/C Switch Is Pressed. The Glass Cannot Be Defogged. (Compressor Does Not Operate (Electric))

Trouble symptom: 

Compressor does not operate after turning the A/C switch to ON and the fan dial to between minimum - maximum.

Trouble causes: 

• Compressor failure
• Outside temperature -12°C (10°F) or less.
• Power supply permission OFF from Hybrid vehicle control ECU assembly.
• Heat pump system failure.
• UART communication failure

Wiring diagram: 

Air conditioning system Ref. to WIRING SYSTEM (CROSSTREK MODEL (HEV))>AIR CONDITIONING SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK A/C CONTROL PANEL  .
   1. Leave the vehicle under the condition at ambient temperature of 15°C (59°F) or more.
   2. Turn to READY ON.
   3. Turn the fan dial to the maximum position.
   4. Turn the A/C switch to ON.

   Is A/C indicator displayed on the A/C control panel?

   Yes  : Go to  2.

   No  : Replace the A/C control panel. Ref. to AIR CONDITIONER (HEV)>CONTROL PANEL .

2. CHECK DTC  .
   1. Turn the temperature control dial at MAX COOL and leave for 16 seconds or more.
   2. Read the following DTCs using Subaru Select Monitor. Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DIAGNOSTIC TROUBLE CODE (DTC) . Ref. to P-HEV HYBRID POWERTRAIN CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
      • Air Conditioner
      • P-HEV Hybrid Powertrain Control

   Are any DTCs displayed? (Current malfunction)

   Yes  : Perform the diagnosis for the displayed DTCs. Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DIAGNOSTIC TROUBLE CODE (DTC) . Ref. to P-HEV HYBRID POWERTRAIN CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   No  : Go to  3.

3. CHECK ELECTRIC COMPRESSOR TARGET REVOLUTION SPEED  .

   Using the Subaru Select Monitor, check the following items in the [Data Monitor] of [Air Conditioner]. Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DATA MONITOR .

   • Electric driven compressor target speed

   Does the display indicate the value greater than zero?

   Yes  : Go to  8.

   No  : Go to  4.

4. CHECK EVAPORATOR SENSOR  .

   Using the Subaru Select Monitor, check the following items in the [Data monitor] of [Air Conditioner]. Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DATA MONITOR .

   • Evaporator Temperature

   Does the display indicate -0.5[°C] (31°F) or more?

   Yes  : Go to  6.

   No  : Go to  5.

5. CHECK EVAPORATOR SENSOR  .

   Check the evaporator sensor, Ref. to AIR CONDITIONER (HEV)>EVAPORATOR SENSOR .

   Is the check result OK?

   Yes  : Go to  6.

   No  : Replace the evaporator sensor. Ref. to AIR CONDITIONER (HEV)>EVAPORATOR SENSOR .

6. CHECK REFRIGERANT PRESSURE SENSOR  .
   1. Leave the vehicle under the condition at ambient temperature of 15°C (31°F) or more.
   2. Using the Subaru Select Monitor, check the following items in the [Data Monitor] of [Air Conditioner]. Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DATA MONITOR .
      • Refrigerant Pressure

   Does the display indicate 0.21[MPa] - 3.03[MPa]?

   Yes  : Go to  8.

   No  : Go to  7.

7. CHECK AMOUNT OF REFRIGERANT PRESSURE  .

   Check the refrigerant pressure. Ref. to AIR CONDITIONER (HEV)>REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET .

   Is the check result OK?

   Yes  : Go to  8.

   No  : Perform repair according to refrigerant pressure inspection.

8. CHECK HEAT PUMP CONTROL MODULE  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the heat pump Control Module connector.
   3. Using a tester, measure the voltage between the heat pump Control Module connector and chassis ground.

      Connector & terminal 

      (i365) No. 40 (+) - Chassis ground (-):

   Is the voltage 11 - 14 V or more?

   Yes  : Go to  9.

   No  : Repair or replace the open, short circuit of the harness.

9. CHECK HEAT PUMP CONTROL MODULE  .

   Replace the heat pump Control Module with a properly functioning part. Ref. to AIR CONDITIONER (HEV)>CONTROL UNIT .

   Is the faulty phenomenon reproduced?

   Yes  : Go to  10.

   No  : Malfunction occurred in the heat pump Control Module.

10. PERFORM UNIT INSPECTION OF HEAT PUMP SYSTEM PARTS  .

    Perform unit inspection of the following parts.

    • Low pressure solenoid valve Ref. to AIR CONDITIONER (HEV)>SOLENOID VALVE>INSPECTION .
    • High pressure solenoid valve Ref. to AIR CONDITIONER (HEV)>SOLENOID VALVE>INSPECTION .
    • Heating expansion valve Ref. to AIR CONDITIONER (HEV)>EXPANSION VALVE>INSPECTION .
    • Cooling expansion valve Ref. to AIR CONDITIONER (HEV)>EXPANSION VALVE>INSPECTION .
    • Interior condenser exit temperature sensor Ref. to AIR CONDITIONER (HEV)>PIPE TEMPERATURE SENSOR>INSPECTION .
    • Exterior condenser exit temperature sensor Ref. to AIR CONDITIONER (HEV)>PIPE TEMPERATURE SENSOR>INSPECTION .
    • Discharge temperature sensorial Ref. to AIR CONDITIONER (HEV)>PIPE TEMPERATURE SENSOR>INSPECTION .
    • Evaporator exit temperature sensor Ref. to AIR CONDITIONER (HEV)>PIPE TEMPERATURE SENSOR>INSPECTION .

    Is the check result OK?

    Yes  : The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

    NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
    If the malfunction still reproduces, replace the compressor, and then perform the diagnosis again.

    No  : Repair it according to unit inspection of parts.