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Home >> Nissan-Datsun >> 2005 >> Maxima SL >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> 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
      G02410050Courtesy 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

  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: Disconnecting Fuel Level Sensor Unit & Fuel Pump Harness Connector
      G02410051Courtesy 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 5 V 

    OK or NG

    • OK: GO TO  5.
    • NG: GO TO  4.
      Fig 3: Checking Voltage Between Fuel Level Sensor Unit & Fuel Pump Terminal 4 & Ground
      G02410052Courtesy of NISSAN MOTOR CO., U.S.A.
  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 - FTTS .

      Continuity should exist. 

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

    OK or NG

    • OK: GO TO  7.
    • NG: GO TO  6.
  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors B1, M11
    • 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.
  8. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

    • INSPECTION END 
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