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Home › Infiniti › 2012 › QX56 AWD › Repair and Diagnosis › Engine Performance › System › Engine Control System - DTCS U0101 To P0153 › DTC P0102, P0103: MAF Sensor › Diagnosis Procedure

Diagnosis Procedure

  1. INSPECTION START

    Confirm the detected DTC.

    Which DTC is detected? 

    P0102: GO TO 2.

    P0103: GO TO  3.

  2. CHECK INTAKE SYSTEM

    Check the following for connection.

    • Air duct
    • Vacuum hoses
    • Intake air passage between air duct to intake manifold

    Is the inspection result normal? 

    YES: GO TO 3.

    NO: Reconnect the parts.

  3. CHECK MAF SENSOR POWER SUPPLY CIRCUIT
    1. Disconnect mass air flow (MAF) sensor harness connector.
    2. Turn ignition switch ON.
    3. Check the voltage between MAF sensor harness connector and ground.
    MAF sensor Ground Voltage
    Connector Terminal
    F31 5 Ground Battery voltage

    Is the inspection result normal? 

    YES: GO TO  5.

    NO: GO TO 4.

  4. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness for open or short between mass air flow sensor and ECM
    • Harness for open or short between mass air flow sensor and IPDM E/R
    • Loose or poor connection for each connector and harness

    : Repair open circuit, short to ground or short to power in harness or connectors.

  5. CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check the continuity between MAF sensor harness connector and ECM harness connector.
      MAF sensor ECM Continuity
      Connector Terminal Connector Terminal
      F31 4 F111 25 Existed
    4. Also check harness for short to ground and short to power.

    Is the inspection result normal? 

    YES: GO TO 6.

    NO: Repair open circuit, short to ground or short to power in harness or connectors.

  6. CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
    1. Check the continuity between MAF sensor harness connector and ECM harness connector.
      MAF sensor ECM Continuity
      Connector Terminal Connector Terminal
      F31 3 F111 22 Existed
    2. Also check harness for short to ground and short to power.

    Is the inspection result normal? 

    YES: GO TO 7.

    NO: Repair open circuit, short to ground or short to power in harness or connectors.

  7. CHECK MASS AIR FLOW SENSOR

    Refer to "COMPONENT INSPECTION (MAF SENSOR) ".

    Is the inspection result normal? 

    YES: GO TO 8.

    NO: Replace mass air flow sensor. Refer to "EXPLODED VIEW ".

  8. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    : INSPECTION END

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