Air Does Not Come Out, Or Airflow Capacity Is Insufficient. (Blower Motor Does Not Rotate)

WARNING: This page is about a different variant/trim than selected.

Trouble symptom:

Airflow capacity is insufficient.
Air does not come out when operating the fan dial.

Trouble causes:

Airflow capacity failure
CAN communication failure
A/C control panel failure
Blower motor 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.

CAUTION: Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>GENERAL DESCRIPTION>CAUTION .

CHECK A/C CONTROL PANEL .
1. Turn the ignition switch to ON.
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 .
  - Target air mix door actuator position (driver's side)
  - Blower Fan Level
3. Turn the temperature control dial at MAX COOL and increase and decrease the A/C control panel fan dial.
Does [Target air mix door actuator position (driver's side)] indicate 0%? Also, does [Blower Fan Level] increase or decrease in accordance with the fan dial operation?

Yes: Go to 2.

No: Go to 5.
CHECK AIRFLOW CAPACITY .
Turn the temperature control dial to MAX COOL, A/C control panel fan dial to MAX, and FRESH/RECIRC switch to RECIRC.

Is the airflow capacity insufficient for the same model?

Yes: Go to 3.

No: 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.
CHECK A/C FILTER .
Check the A/C filter. Ref. to AIR CONDITIONER (HEV)>A/C FILTER .

Is the check result OK?

Yes: Go to 4.

No: Clean or replace the A/C filter. Ref. to AIR CONDITIONER (HEV)>A/C FILTER .
CHECK EACH DUCT .
Check each duct joint for disconnection or clogging.

Is the check result OK?

Yes: Go to 5.

No: Repair the faulty duct.
CHECK A/C CONTROL PANEL .
1. Turn the fan dial to the maximum position.
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 .
- Blower Fan Level Does [Blower Fan Level] indicate "90 - 100"?
Yes: Go to 6.

No: Replace the A/C control panel. Ref. to AIR CONDITIONER (HEV)>CONTROL PANEL .
CHECK A/C CONTROL PANEL .
1. Turn the fan dial to the minimum position.
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 .
- Blower Fan Level
Does [Blower Fan Level] indicate "1 - 16"?

Yes: Go to 7.

No: Replace the A/C control panel. Ref. to AIR CONDITIONER (HEV)>CONTROL PANEL .
CHECK CONNECTOR .
1. Turn the ignition switch to OFF.
2. Check for poor contact of connector.
Is the check result OK?

Yes: Go to 8.

No: Repair the connector.
CHECK FUSE .
1. Remove the fuse from fuse and relay box and the fuse from the main fuse box.
2. Check the condition of fuse.
Is the check result OK?

Yes: Go to 9.

No: Replace the fuse. If the replaced fuse blows out easily, repair the ground short circuit in harness between the pressure switch and fuse.
CHECK BLOWER MOTOR RELAY ON SIGNAL .
1. Turn the ignition switch to ON.
2. Turn the ON/OFF switch to OFF.
3. Using a tester, measure the voltage between the A/C control panel connector (il81) and chassis ground.
  Connector and terminal
  
  (i 181) No. 11 (+) - Chassis ground (-):
Is the voltage 10 V or more?

Yes: Go to 10.

No:
- Check for open or short circuit in the harness between fuse and ECM.
- Check the blower relay connector and relay unit. Ref. to AIR CONDITIONER (HEV)>RELAY AND FUSE .
CHECK BLOWER MOTOR RELAY ON SIGNAL .
1. Turn to READY ON.
2. Turn the ON/OFF switch to ON.
3. Using a tester, measure the voltage between the A/C control panel connector (i88) and chassis ground.
  Connector and terminal
  
  (i 181) No. 11 (+) - Chassis ground (-):
Is the voltage 0 V?

Yes: Go to 11.

No: Replace the A/C control panel. Ref. to AIR CONDITIONER (HEV)>CONTROL PANEL .
CHECK BLOWER MOTOR POWER SUPPLY CIRCUIT .
1. Turn to READY OFF.
2. Turn the ignition switch to ON.
3. Turn the ON/OFF switch to ON.
4. Use a tester to measure the voltage between the blower motor connector (i 185) and chassis ground.
  Connector and terminal
  
  (i 185) No. 2 (+) - Chassis ground (-):
Is the voltage 10 V or more?

Yes: Go to 12.

No:
- Check the blower motor power supply line harness for open circuit or connector disconnection.
- Check the blower relay connector and relay unit. Ref. to AIR CONDITIONER (HEV)>RELAY AND FUSE .
CHECK BLOWER MOTOR UNIT .
Check the blower motor. Ref. to AIR CONDITIONER (HEV)>BLOWER MOTOR .

Is the check result of the blower motor OK?

Yes: Go to 13.

No: Replace the blower motor. Ref. to AIR CONDITIONER (HEV)>BLOWER MOTOR .
CHECK HARNESS (OPEN CIRCUIT) .
1. Turn the ignition switch to OFF.
2. Disconnect the power transistor and A/C control panel connector.
3. Using a tester, measure the resistance between harness terminals.
  Connector and terminal
  
  (il83) No. 1 - (il85) No. 1:
  
  (il83) No. 4 - (i80) No. 5:
  
  (il83) No. 3 - (i80) No. 6:
  
  (i 183) No. 2 - Chassis ground:
Is the resistance less than 1 Ω?

Yes: Go to 14.

No: Repair or replace the open circuit of harness.
CHECK HARNESS (GROUND SHORT CIRCUIT) .
Use a tester to measure the harness resistance between the power transistor connector and chassis ground.

Connector and terminal

(i 183) No. 4 - Chassis ground:

Is the resistance less than 1 Ω?

Yes: Repair or replace the short circuit of the harness.

No: Go to 15.
CHECK POWER TRANSISTOR .
Replace the power transistor with a properly functioning part.

Does the blower motor rotate?

Yes: Replace the power transistor. Ref. to AIR CONDITIONER (HEV)>POWER TRANSISTOR .

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