1.CHECK CONNECTOR. 1) Check connecting condition of the A/C CM connector and air mix door actuator LH connector. 2) Read the DTC using Subaru Select Monitor. Read Diagnostic Trouble Code (DTC) | | Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B1446 AIR MIX DOOR ACTUATOR CIRCUIT STUCK (DRIVER) | 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, change the setting of «Air mix Dr Act Trgt Open Angle(Driver’s)» from the A/C diagnosis and perform the system operation check. System Operation Check Mode | Did the air mix door actuator LH move to the specified target opening angle- | Air mix door actuator LH circuit is normal. | Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B1446 AIR MIX DOOR ACTUATOR CIRCUIT STUCK (DRIVER) |
3.CHECK HARNESS. 1) Turn the ignition switch to ON. 2) Using the tester, measure the voltage between terminals. Connector & terminal (i174) No. 1 (+) — No. 3 (−): | Is the voltage 4.5 — 5.0 V- | Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B1446 AIR MIX DOOR ACTUATOR CIRCUIT STUCK (DRIVER) | Repair or replace the open, short circuit of the harness. |
4.CHECK HARNESS (OPEN CIRCUIT). 1) Disconnect the connector from A/C CM. 2) Using a tester, check continuity between terminals. Connector & terminal (i174) No. 5 — (i80) No. 17: (i174) No. 1 — (i80) No. 12: (i174) No. 3 — (i181) No. 18: (i174) No. 6 — (i181) No. 21: (i174) No. 7 — (i181) No. 11: | | Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B1446 AIR MIX DOOR ACTUATOR CIRCUIT STUCK (DRIVER) | Repair or replace the open circuit of harness. |
5.CHECK AIR MIX DOOR ACTUATOR LH. Check the air mix door actuator LH parts. Air Mix Door Actuator > INSPECTION | Is the air mix door actuator LH normal- | Replace the A/C CM. Control Unit > REMOVAL | Replace the air mix door actuator LH. Air Mix Door Actuator > REMOVAL |