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Home >> Nissan-Datsun >> 2006 >> Quest Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P0137 To P0445 >> DTC P0181 FTT Sensor >> Diagnostic Procedure
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Diagnostic Procedure

  1. CHECK GROUND CONNECTIONS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten three ground screws on the body. Refer to , "GROUND INSPECTION ".
      Fig 1: Locating Body Ground Screws E24, E15, F9 And E133
      G04196499Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK : GO TO 2.

    NG : Repair or replace ground connections.

  2. CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT 
    1. Disconnect "fuel level sensor unit and fuel pump" harness connector.
    2. Turn ignition switch ON.
      Fig 2: Identifying Fuel Level Sensor Unit
      G04196734Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between "fuel level sensor unit and fuel pump" terminal 4 and ground with CONSULT-II or tester.

      Voltage: Approximately 5V 

    OK or NG 

    OK : GO TO  4.

    NG : GO TO 3.

    Fig 3: Checking Voltage Between Terminal No. 4 & Ground
    G04179852Courtesy of NISSAN MOTOR CO., U.S.A.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors B106, E138
    • Harness connectors B148, B251
    • Harness for open or short between ECM and "fuel level sensor unit and fuel pump"

      : Repair harness or connector.

  4. CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect TCM harness connector.
    4. Check harness continuity between "fuel level sensor unit and fuel pump" terminal 5 and ECM terminal 67, TCM terminal 42. Refer to WIRING DIAGRAM .

      Continuity should exist. 

    5. Also check harness for short to ground and short to power.

    OK or NG 

    OK : GO TO  6.

    NG : GO TO 5.

  5. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E5, F14
    • Harness connectors E19, F33
    • Harness connectors B106, E138
    • Harness connectors B148, B251
    • Harness for open or short between "fuel level sensor unit and fuel pump" and ECM.
    • Harness for open or short between "fuel level sensor unit and fuel pump" and TCM.

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

  6. CHECK FUEL TANK TEMPERATURE SENSOR 

    Refer to , "COMPONENT INSPECTION ".

    OK or NG 

    OK : GO TO 7.

    NG : Replace "fuel level sensor unit and fuel pump".

  7. CHECK INTERMITTENT INCIDENT 

    Refer to , "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    : INSPECTION END 

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