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Home >> Infiniti >> 2012 >> M37 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P0137 Through P0456 >> 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 

    Refer to "CONSULT FUNCTION ".

    Is the inspection result normal? 

    YES: GO TO 3.

    NO: Go 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" harness connector.
    3. Turn ignition switch ON.
    4. Check the voltage between "fuel level sensor unit and fuel pump" harness connector and ground.
      Fuel level sensor unit and fuel pump 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 connectors B201, M117
    • Harness for open or short between ECM and "fuel level sensor unit and fuel pump"

      : 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" harness connector and combination meter harness connector.
      Fuel level sensor unit and fuel pump 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 connectors B201, M117
    • Harness for open or short between "fuel level sensor unit and fuel pump" and combination meter

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

  7. CHECK FUEL TANK TEMPERATURE SENSOR 

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 8.

    NO: Replace "fuel level sensor unit and fuel pump". Refer to "EXPLODED VIEW ".

  8. CHECK INTERMITTENT INCIDENT 

    Refer to "INTERMITTENT INCIDENT ".

    : INSPECTION END

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