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Home >> Nissan-Datsun >> 2008 >> Maxima SL >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P0137 To P0447 >> 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 four ground screws on the body.

      Refer to "GROUND INSPECTION ."

      Fig 1: Checking Ground Connections
      G04915248Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  2.

    NG: Repair or replace ground connections.

  2. CHECK DTC WITH UNIFIED METER AND A/C AMP  .

    Refer to "SELF-DIAGNOSTIC RESULTS ."

    OK or NG 

    OK: GO TO  3.

    NG: GO TO "FUEL LEVEL SENSOR SIGNAL INSPECTION 1 ."

  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.
      Fig 2: Identifying Fuel Level Sensor Unit And Fuel Pump Harness Connector
      G04915485Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between "fuel level sensor unit and fuel pump" terminal 4 and ground with CONSULT-III or tester.

      Voltage: Approximately 5V 

      Fig 3: Checking Voltage Between Fuel Level Sensor Unit And Fuel Pump Terminal 4 And Ground
      G04875130Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  5.

    NG: GO TO  4.

  4. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M81, B20
    • Harness for open or short between ECM and "fuel level sensor unit and fuel pump"

    >> Repair harness or connector.

  5. CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect "unified meter and A/C amp." harness connector.
    3. Check harness continuity between "fuel level sensor unit and fuel pump" terminal 5 and "unified meter and A/C amp." terminal 36. Refer to Wiring Diagram.

      Continuity should exist  .

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

    OK or NG 

    OK: GO TO  7.

    NG: GO TO  6.

  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M81, B20
    • Harness for open or short between "fuel level sensor unit and fuel pump" and "unified meter and A/C amp."

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

  7. CHECK FUEL TANK TEMPERATURE SENSOR 

    Refer to "COMPONENT INSPECTION ."

    OK or NG 

    OK: GO TO  8.

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

  8. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ."

    >> INSPECTION END 

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