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Home >> Infiniti >> 2013 >> M56 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS U0101 To P0183 >> DTC P0181: FTT Sensor >> Diagnosis Procedure
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Diagnosis Procedure

  1. INSPECTION START 

    Confirm the detected malfunction (A or B). Refer to "DTC LOGIC ".

    Which malfunction is detected? 

    YES: GO TO 2.

    NO: GO TO  7.

  2. CHECK DTC WITH COMBINATION METER 

    Check DTC with combination meter. Refer to "CONSULT FUNCTION ".

    Is the inspection result normal? 

    YES: GO TO 3.

    NO: Proceed to "COMPONENT FUNCTION CHECK ".

  3. CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect "fuel level sensor unit and fuel pump (main)" harness connector.
    3. Turn ignition switch ON.
    4. Check the voltage between "fuel level sensor unit and fuel pump (main)" harness connector and ground.
      Fuel level sensor unit and fuel pump (main) Ground Voltage (V)
      Connector Terminal
      B241 4 Ground Approx. 5

      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 ECM and "fuel level sensor unit and fuel pump (main)"
    • Loose or poor connection for each connector and harness

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

  5. CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect "combination meter" harness connector.
    3. Check the continuity between "fuel level sensor unit and fuel pump (main)" harness connector and "combination meter" harness connector.
      Fuel level sensor unit and fuel pump (main) Combination meter Continuity
      Connector Terminal Connector Terminal
      B241 5 M53 24 Existed
    4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  7.

      NO: GO TO 6.

  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness for open or short between "fuel level sensor unit and fuel pump (main)" and "combination meter"
    • Loose or poor connection for each connector and harness

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

  7. CHECK FUEL TANK TEMPERATURE SENSOR 

    Check FTT sensor. Refer to "COMPONENT INSPECTION (FUEL TANK TEMPERATURE SENSOR) ".

    Is the inspection result normal? 

    YES: GO TO 8.

    NO: Replace fuel level sensor unit and fuel pump (main). Refer to "REMOVAL AND INSTALLATION ".

  8. CHECK INTERMITTENT INCIDENT 

    Refer to "INTERMITTENT INCIDENT ".

    : INSPECTION END

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