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P0101

B: DTC P0101 - MASS AIR FLOW SENSOR CIRCUIT RANGE/PERFORMANCE PROBLEM (LOW IN PUT)

DTC DETECTING CONDITION:
- Two consecutive driving cycles with fault

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

CHECK: Does the Subaru Select Monitor or OBD-II general scan tool indicate DTC P0102 or P0103?

YES: Inspect DTC P0102 or P0103 using "10 Diagnostics Chart with Trouble Code". P0102 P0103

NOTE: In this case, it is not necessary to inspect DTC P0101.

NO: Go to step 10B2.

10B2: CHECK INPUT SIGNAL FOR ECM.
1) Turn ignition switch to ON.

Connector & Terminal (B136) No.5 (+) - Chassis Ground (-):





2) Measure voltage between ECM connector and chassis ground while throttle valve is fully closed.

CHECK: Is the voltage between 0.2 V and 1.0 V?

YES: Go to step 10B3.

NO: Check throttle position sensor circuit.

10B3: CHECK INPUT SIGNAL FOR ECM.

Connector & Terminal (B136) No.5 (+) - Chassis Ground (-):




Measure voltage between ECM connector and chassis ground while throttle valve is fully opened.

CHECK: Is the voltage between 4.2 V and 4.7 V?

YES: Replace mass air flow sensor.

NO: Check throttle position sensor circuit.