DTC P0103 Mass Or Volume Air Flow Circuit High Input

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

DTC DETECTING CONDITION:

Detect as soon as malfunction occurs.
GENERAL DESCRIPTION < Ref. to DTC P0103 MASS OR VOLUME AIR FLOW CIRCUIT HIGH INPUT , Diagnostic Trouble Code (DTC) Detecting Criteria. >

TROUBLE SYMPTOM:

Erroneous idling
Engine stalls.
Poor driving performance

CAUTION: After repair or replacement of faulty parts, conduct Clear Memory Mode < Ref. to , OPERATION , Clear Memory Mode.> and Inspection Mode < Ref. to , PROCEDURE , Inspection Mode.>.

WIRING DIAGRAM:

Fig 1: DTC P0103 Mass Or Volume Air Flow Circuit High Input

Courtesy of SUBARU OF AMERICA, INC.

DTC P0103 MASS OR VOLUME AIR FLOW CIRCUIT HIGH INPUT DIAGNOSIS

Step	Check	Yes	No
1. CONNECT SUBARU SELECT MONITOR OR THE OBD-II GENERAL SCAN TOOL, AND READ DATA. Turn the ignition switch to OFF. Connect the Subaru Select Monitor or OBD-II general scan tool to data link connector. Turn the ignition switch to ON and Subaru Select Monitor or OBD-II general scan tool switch to ON. Start the engine. Read the mass air flow sensor voltage using Subaru Select Monitor or OBD-II general scan tool. NOTE: Subaru Select Monitor For detailed operation procedure, refer to the "READ CURRENT DATA FOR ENGINE". < Ref. to , SUBARU SELECT MONITOR . > OBD-II general scan tool For detailed operation procedures, refer to the OBD-II general scan tool instruction manual .	Is the measured value within 0.2 to 4.7 V?	Even if malfunction indicator light lights up, the circuit has returned to a normal condition at this time.	Go to step 2.
2. CHECK HARNESS BETWEEN ECM AND MASS AIR FLOW SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from mass air flow sensor. Turn the ignition switch to ON. Measure the voltage between mass air flow sensor connector and chassis ground. Connector & terminal (B3) No. 3 (+) - Chassis ground (-):	Is the measured value more than 5 V?	Repair the battery short of harness between mass air flow sensor connector and ECM connector.	Go to step 3.
3. CHECK HARNESS BETWEEN ECM AND MASS AIR FLOW SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connector and mass air flow sensor connector. Connector & terminal (B3) No. 2 - (B136) No. 31:	Is the measured value less than 1 Ω?	Replace the mass air flow sensor. < Ref. to MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR . >	Repair the open harness between mass air flow sensor connector and ECM connector.