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Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Qr25DE >> DTC P0181: FTT Sensor >> Diagnostic Procedure
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Diagnostic Procedure

  1. 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.
      Fig 1: Disconnecting Fuel Level Sensor Unit & Fuel Pump Harness Connector
      G00777830Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between "fuel level sensor unit and fuel pump" terminal 4 and ground with CONSULT-II or tester.

      Voltage: Approximately 5V 

    5. Fig 2: Checking Voltage Between Fuel Level Sensor Unit & Fuel Pump Terminal 4 & Ground
      G00777831Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO  3.
    2. NG: GO TO 2.
  2. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M59, F27
    • Harness connectors B3, M16
    • Harness for open or short between ECM and "fuel level sensor unit and fuel pump"
      1. Repair harness or connector.
  3. CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Check harness continuity between "fuel level sensor unit and fuel pump" terminal 5 and body ground. Refer to WIRING DIAGRAM .

      Continuity should exist. 

    3. Also check harness for short to power.

    OK or NG 

    1. OK: GO TO 4.
    2. NG: Repair open circuit or short to power in harness or connectors.
  4. CHECK FUEL TANK TEMPERATURE SENSOR

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK: GO TO 5.
    2. NG: Replace fuel level sensor unit.
  5. CHECK INTERMITTENT INCIDENT 

    Perform "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    1. INSPECTION END