Subaru Legacy BN/BS (2015-2019) Service Manual: Dtc b1439 mode door actuator circuit short-circuit

Subaru Legacy BN/BS (2015-2019) Service Manual / Hvac system (diagnostics) / Diagnostic procedure with diagnostic trouble code (dtc) / Dtc b1439 mode door actuator circuit short-circuit

DTC DETECTING CONDITION:

Mode door actuator potentiometer circuit is shorted.

TROUBLE SYMPTOM:

Vent does not change.

WIRING DIAGRAM:

Air conditioning system Air Conditioning System > WIRING DIAGRAM

STEP	CHECK	YES	NO
1.CHECK CONNECTOR. 1) Check connecting condition of the A/C CM connector and mode door actuator connector. 2) Read the DTC using Subaru Select Monitor. Read Diagnostic Trouble Code (DTC)	Is B1439 displayed-	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B1439 MODE DOOR ACTUATOR CIRCUIT SHORT-CIRCUIT	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. 1) Disconnect the mode door actuator. 2) Read the DTC using Subaru Select Monitor. Read Diagnostic Trouble Code (DTC)	Is B1438 displayed-	Replace the mode door actuator. Mode Door Actuator > REMOVAL	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B1439 MODE DOOR ACTUATOR CIRCUIT SHORT-CIRCUIT
3.CHECK HARNESS (SHORTED BETWEEN LINES AND SHORTED TO GROUND). 1) Disconnect the connector from A/C CM. 2) Using a tester, check continuity between terminals. Connector & terminal (i176) No. 2 — No. 3: (i176) No. 3 — Chassis ground:	Is there continuity-	Repair or replace the short circuit of the harness.	Replace the A/C CM. Control Unit > REMOVAL

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Dtc b1438 mode door actuator circuit open

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Other materials:

Preparation tool
1. SPECIAL TOOLILLUSTRATIONTOOL NUMBERDESCRIPTIONREMARKS — (Newly adopted tool)SUBARU SELECT MONITOR 4Used for setting of each function and troubleshooting for electrical system.NOTE:For detailed operation procedures of Subaru Select Monitor 4, refer to “Application help”.2. GENERAL TO ...