DTC B1443: Mode Door Actuator Circuit Stuck

DTC detecting condition: 

Mode door actuator is locked.

Trouble symptom: 

Vent does not change.

Wiring diagram: 

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

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK CONNECTOR  .
   1. Check connecting condition of the A/C control panel connector and mode door actuator connector.
   2. Turn the ignition switch to ON.
   3. Read the DTC of [Air Conditioner] using the Subaru Select Monitor. Ref. to AIR CONDITIONER (DIAGNOSTICS) (EXCEPT FOR HEV)>DIAGNOSTIC TROUBLE CODE (DTC) .

      Is DTC B1443 displayed? (Current malfunction)

      Yes:  Go to  2.

      No:  Even if DTC is displayed, 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.
2. CHECK ACTUATOR  .

   Using the Subaru Select Monitor, check the following items in the [Active Test] of [Air Conditioner]. Ref. to AIR CONDITIONER (DIAGNOSTICS) (EXCEPT FOR HEV)>ACTIVE TEST .

   • Mode Door Actuator Opening Angle Target

   Did the mode door actuator move to the specified target opening angle?

   Yes:  Mode door actuator circuit is normal.

   No:  Go to  3.

3. CHECK HARNESS  .

   Measure the voltage between mode door actuator connector terminals using a tester.

   Connector and terminal 

   (i176) No. 3 (+) - (i176) No. 1 (-):

   Is the voltage 4.5 - 5.5 V?

   Yes:  Go to  4.

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

4. CHECK HARNESS (OPEN CIRCUIT)  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the connector from the A/C control panel.
   3. Using a tester, check the continuity between A/C control panel connector and mode door actuator connector terminals.

      Connector and terminal 

      (i176) No. 3 - (i88) No. 16:

      (i176) No. 1 - (i88) No. 30:

      (i176) No. 2 - (i88) No. 33:

      (i176) No. 4 - (i88) No. 23:

      (i176) No. 5 - (i88) No. 24:

      Is there continuity?

      Yes:  Go to  5.

      No:  Repair or replace the open circuit of harness.

5. CHECK MODE DOOR ACTUATOR  .

   Check the mode door actuator parts. Ref. to AIR CONDITIONER (EXCEPT FOR HEV)>MODE DOOR ACTUATOR .

   Is the mode door actuator OK?

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

   No:  Replace the mode door actuator. Ref. to AIR CONDITIONER (EXCEPT FOR HEV)>MODE DOOR ACTUATOR .