Unable To Switch Vents

Trouble symptom: 

• Unable to switch blow vents.
• Even when the mode dial is operated, blower vent does not switch to FACE → FACE2 → B/L → FOOT → F/D.

Trouble causes: 

• Mode actuator failure
• UART communication failure

Courtesy of SUBARU OF AMERICA, INC.

1. 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 .
      • Mode Door Actuator Position Target
   3. Operate the mode change switch.

   Does the value of [Mode Door Actuator Position Target] change along with the operation?

   Yes  : Go to  2.

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

2. CHECK DTC  .
   1. Turn the DEF switch to ON and then leave it for 16 seconds or more.
   2. Read the DTC of [Air Conditioner] using the Subaru Select Monitor. Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is DTC B1438, B1439 or B1443 displayed? (Current malfunction)

   Yes  : Perform the diagnosis for the displayed DTC B1438, B1439 or B1443. Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)>DTC B1438 MODE DOOR ACTUATOR CIRCUIT OPEN . Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)>DTC B1439 MODE DOOR ACTUATOR CIRCUIT SHORT-CIRCUIT . Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)>DTC B1443 MODE DOOR ACTUATOR CIRCUIT STUCK .

   No  : Go to  3.

3. CHECK DTC  .
   1. Set the mode change switch to VENT, and wait for 16 seconds or more.
   2. Read the DTC of [Air Conditioner] using the Subaru Select Monitor. Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is DTC B1438, B1439 or B1443 displayed? (Current malfunction)

   Yes  : Perform the diagnosis for the displayed DTC B1438, B1439 or B1443. Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)>DTC B1438 MODE DOOR ACTUATOR CIRCUIT OPEN . Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)>DTC B1439 MODE DOOR ACTUATOR CIRCUIT SHORT-CIRCUIT . Ref. to AIR CONDITIONER (DIAGNOSTICS) (HEV)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)>DTC B1443 MODE DOOR ACTUATOR CIRCUIT STUCK .

   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.