DTC P0103: Mass Or Volume Air Flow Sensor "A" Circuit High: Notes

1. - 

DTC detecting condition: 

Immediately at fault recognition

Trouble symptom: 

• Improper idling
• Engine stall
• Poor driving performance

1. CHECK DTC  .
   1. Turn the ignition switch to ON.
   2. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to COMMON (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)

   Is DTC P06B4 displayed? (Current code)

   Yes  : Check for DTC P06B4. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)>DTC P06B4 SENSOR POWER SUPPLY "B" CIRCUIT LOW

   No  : Go to  2.

2. CHECK DTC  .

   Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to COMMON (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)

   Is DTC P06B5 displayed? (Current code)

   Yes  : Check for DTC P06B5. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)>DTC P06B5 SENSOR POWER SUPPLY "B" CIRCUIT HIGH

   No  : Go to  3.

3. CHECK DATA MONITOR  .
   1. Start the engine.
   2. Using the Subaru Select Monitor, read the value in [Mass Air Flow].
      NOTE:

      For detailed operation procedures, refer to "COMMON (DIAGNOSTICS)". Ref. to  COMMON (DIAGNOSTICS)>DATA MONITOR 

   Is the value of [Mass Air Flow] 232.32 g/s (30.74 lb/min) or more?

   Yes  : Go to  4.

   No  : Even if DTC is detected, 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. 

4. CHECK FOR POOR CONTACT  .

   Check for poor contact of mass air flow and intake air temperature sensor connector.

   Is there poor contact of mass air flow and intake air temperature sensor connector?

   Yes  : Repair the poor contact of mass air flow and intake air temperature sensor connector.

   No  : Replace the mass air flow and intake air temperature sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>MASS AIR FLOW AND INTAKE AIR TEMPERATURE SENSOR