Air Does Not Come Out, Or Airflow Capacity Is Insufficient. (Blower Motor Does Not Rotate)
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 .
- CHECK A/C CONTROL PANEL
.
- Turn the ignition switch to ON.
- Using the Subaru Select Monitor, check the following items in the [Data Monitor] of [Air Conditioner]. Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DATA MONITOR .
- Air mix door actuator position (driver's side)
- Blower Fan Level
- Turn the temperature control dial at MAX COOL and increase and decrease the A/C control panel fan dial.
Does [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
.
- Turn the fan dial to the maximum position.
- 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 "89 - 100"?
Yes : Go to 6.
No : Replace the A/C control panel. Ref. to AIR CONDITIONER (HEV)>CONTROL PANEL .
- CHECK A/C CONTROL PANEL
.
- Turn the fan dial to the minimum position.
- 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 - 17"?
Yes : Go to 7.
No : Replace the A/C control panel. Ref. to AIR CONDITIONER (HEV)>CONTROL PANEL .
- CHECK CONNECTOR
.
- Turn the ignition switch to OFF.
- Check for poor contact of connector
Is the check result OK?
Yes : Go to 8.
No : Repair the connector.
- CHECK FUSE
.
- Remove the fuse from fuse & relay box and the fuse from the main fuse box.
- 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
.
- Turn the ON/OFF switch to OFF.
- Turn the ignition switch to ON.
- Using a tester, measure the voltage between the A/C control panel connector (i 181) and chassis ground.
Connector & terminal
(i181) 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
.
- Turn to READY ON.
- Turn the ON/OFF switch to ON.
- Using a tester, measure the voltage between the A/C control panel connector (i88) and chassis ground.
Connector & terminal
(i181) 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
.
- Turn the ignition switch to ON.
- Turn the ON/OFF switch to ON.
- Use a tester to measure the voltage between the blower motor connector (i 185) and chassis ground.
Connector & terminal
(i185) 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 connect 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)
.
- Turn the ignition switch to OFF.
- Disconnect the power transistor and A/C control panel connector.
- Using a tester, measure the resistance between harness terminals.
Connector & terminal
(il83) No. 1 - (il85) No. 1:
(il83) No. 4 - (i80) No. 5:
(il83) No. 3 - (i80) No. 6:
(i183) 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 & terminal
(i183) 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 .