Nothing Is Displayed On The Screen Or Indicators Do Not Illuminate

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

Trouble symptom:

When the AUTO button is turned to ON with IGN ON, nothing is displayed on the screen or indicators do not illuminate.

Trouble causes:

A/C control panel power supply circuit failure
CAN communication failure
UART communication failure

Wiring diagram:

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

Courtesy of SUBARU OF AMERICA, INC.

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

Courtesy of SUBARU OF AMERICA, INC.

Courtesy of SUBARU OF AMERICA, INC.

CHECK FUSE .
1. Turn the ignition switch to OFF.
2. Remove the fuses No. 8 and 14 from fuse & relay box.
3. Check the condition of fuse.
Is the check result OK?

Yes : Go to 2.

No : Replace the fuse. If the replaced fuse blows out easily, repair the ground short circuit in harness between the fuse - A/C control panel.
CHECK CONNECTOR .
Check poor contact of A/C control panel connector, A/C Control Module connector and coupling connector.

Is the check result OK?

Yes : Go to 3.

No : Repair the connector.
CHECK A/C CONTROL PANEL POWER SUPPLY CIRCUIT (OPEN OR SHORT) .
1. Remove the A/C control panel. Ref. to AIR CONDITIONER (HEV)>CONTROL PANEL .
2. Disconnect the A/C control panel connector.
3. Turn the ignition switch to ON.
4. Measure the voltage between A/C control panel connector terminal and chassis ground.
  Connector & terminal
  
  (i80) No. 2 (+) - Chassis ground (-):
  
  (i329) No. 4 (+) - Chassis ground (-):
Is the voltage 10 V or more?

Yes : Go to 4.

No : Check for open or short circuit in the harness between A/C control panel and fuse.
CHECK A/C CONTROL PANEL GROUND CIRCUIT (OPEN) .
1. Turn the ignition switch to OFF.
2. Measure the resistance of harness between A/C control panel and chassis ground.
  Connector & terminal
  
  (i80) No. 3 - Chassis ground:
Is the resistance less than 10 Ω?

Yes : Go to 5.

No : Repair the harness for ground line.
CHECK A/C CONTROL MODULE POWER SUPPLY CIRCUIT (OPEN OR SHORT) .
1. Install the A/C control panel. Ref. to AIR CONDITIONER (HEV)>CONTROL PANEL .
2. Disconnect the A/C Control Module connector.
3. Turn the ignition switch to ON.
4. Measure the voltage between A/C Control Module connector terminal and chassis ground.
  Connector & terminal
  
  (i80) No. 2 (+) - Chassis ground (-):
  
  (i80) No. 1 (+) - Chassis ground (-):
  
  (i80) No. 21 (+) - Chassis ground (-):
Is the voltage 10 V or more?

Yes : Go to 6.

No : Check for open or short circuit in the harness between A/C Control Module and fuse.
CHECK A/C CONTROL MODULE GROUND CIRCUIT (OPEN CIRCUIT) .
1. Turn the ignition switch to OFF.
2. Measure the resistance of harness between A/C Control Module and chassis ground.
  Connector & terminal
  
  (i80) No. 3 - Chassis ground:
Is the resistance less than 10 Ω?

Yes : Go to 7.

No : Repair the harness for ground line.
CHECK COMMUNICATION CIRCUIT (OPEN) .
Measure the resistance of harness between A/C control panel and A/C Control Module.

Connector & terminal

(i329) No. 6 - (i80) No. 19:

(i329) No. 7 - (i80) No. 20:

Is the resistance less than 10 Ω?

Yes : Go to 8.

No : Repair or replace the open circuit of harness.
CHECK COMMUNICATION CIRCUIT (SHORT CIRCUIT TO GROUND) .
Using a tester, measure the harness resistance between communication circuit harness and chassis ground.

Connector & terminal

(i80) No. 19 - Chassis ground:

(i80) No. 20 - Chassis ground:

Is the resistance less than 10 Ω?

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

No : Go to 9.
CHECK HARNESS (SHORTED BETWEEN LINES) .
Using the tester, measure the resistance between terminals.

Connector & terminal

(i80) No. 19 - (i80) No. 20:

Is the resistance less than 10 Ω?

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

No : Go to 10.
CHECK FOR POOR CONTACT .
Check poor contact of A/C control panel connector.

Is the check result OK?

Yes : Replace the A/C control panel. Ref. to AIR CONDITIONER (HEV)>CONTROL PANEL .

No : Repair the connector.