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P0103

DTC P0103 - MASS AIR FLOW SENSOR CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:
- Immediately at fault recognition

TROUBLE SYMPTOM:
- Erroneous idling
- Engine stalls.
- Poor driving performance

CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY and INSPECTION MODES. Clearing Diagnostic Trouble Codes





WIRING DIAGRAM:

10D1: CONNECT SUBARU SELECT MONITOR OR THE OBD-II GENERAL SCAN TOOL, AND READ DATA.
1) Turn Ignition switch to OFF.





2) Connect Subaru Select Monitor or the OBD-II general scan tool to data link connector.

3) Turn ignition switch to ON and Subaru Select Monitor or the OBD-II general scan tool switch to ON.

4) Start engine.

5) Read data of mass air flow sensor signal using Subaru Select Monitor or OBD-II general scan tool.

NOTE:
- Subaru Select Monitor. For detailed operation procedure, refer to the "READ CURRENT DATA SHOWN ON DISPLAY FOR ENGINE".

- OBD-II general scan tool. For detailed operation procedures, refer to the OBD-II General Scan Tool Procedures.

CHECK: Is the value equal to or more than 0 g/sec (0 lb/mm) or 0.3 V and equal to or less than 186 g/sec (25 lb/mm) or 5.0 V?

YES: Even if MIL lights up, the circuit has returned to a normal condition at this time.

NO: Go to step 10D2.

10D2: CHECK HARNESS BETWEEN ECM AND MASS AIR FLOW SENSOR CONNECTOR.
1) Turn ignition switch to OFF and Subaru Select Monitor or the OBD-II general scan tool switch to OFF.

2) Disconnect connector from mass air flow sensor.

3) Turn ignition switch to ON and Subaru Select Monitor or the OBD-II general scan tool switch to ON.

4) Read data of mass air flow sensor signal using Subaru Select Monitor or OBD-II general scan tool.

NOTE:
- Subaru Select Monitor. For detailed operation procedure, refer to the "READ CURRENT DATA SHOWN ON DISPLAY FOR ENGINE".

- OBD-II general scan tool. For detailed operation procedures, refer to the OBD-II General Scan Tool Procedures.

CHECK: Is the value more than 186 9/sec (25 lb/mm) or 5 V?

YES: Repair battery short circuit in harness between mass air flow sensor and ECM connector. After repair, replace ECM.

NO: Replace mass air flow sensor.