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Diagnostic Procedure

WARNING: This page is about a different car, the 2006 Nissan Pathfinder. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK OVERALL FUNCTION 
    1. Turn ignition switch ON.
    2. Pinch fuel feed hose with two fingers.

      Fuel pressure pulsation should be felt on the fuel feed hose for 1 second after ignition switch is turned ON. 

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO 2.

    Fig 1: Identifying Fuel Feed Hose
    G04173805Courtesy of NISSAN MOTOR CO., U.S.A.
  2. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Turn ignition switch ON.
    4. Check voltage between ECM terminal 113 and ground with CONSULT-II or tester.

    Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  5.

    NG: GO TO 3.

    Fig 2: Checking Voltage Between ECM Terminal 113 And Ground
    G04173806Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II 

    Check voltage between IPDM E/R terminal 46 and ground with CONSULT-II or tester.

    Voltage: Battery voltage 

    OK or NG 

    OK: GO TO 4.

    NG: GO TO  12.

    Fig 3: Checking Voltage Between IPDM E/R Terminal 46 And Ground
    G04173807Courtesy of NISSAN MOTOR CO., U.S.A.
  4. DETECT MALFUNCTIONING PART 

    Check harness for open or short between IPDM E/R and ECM

    : Repair harness or connectors.

  5. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-III 
    1. Turn ignition switch OFF.
    2. Reconnect all harness connectors disconnected.
    3. Disconnect "fuel level sensor unit and fuel pump" harness connector.
    4. Turn ignition switch ON.
      Fig 4: Checking Fuel Pump Power Supply Circuit-III
      G04173808Courtesy of NISSAN MOTOR CO., U.S.A.
    5. Check voltage between "fuel level sensor unit and fuel pump" terminal 1 and ground with CONSULT-II or tester.

      Voltage: Battery voltage should exist for 1 second after ignition switch is turned ON. 

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

    OK or NG 

    OK: GO TO  9.

    NG: GO TO 6.

    Fig 5: Checking Voltage Between "Fuel Level Sensor Unit And Fuel Pump" Terminal 1 And Ground
    G04173809Courtesy of NISSAN MOTOR CO., U.S.A.
  6. CHECK 15A FUSE 
    1. Turn ignition switch OFF.
    2. Disconnect 15A fuse.
    3. Check 15A fuse.

    OK or NG 

    OK: GO TO 7.

    NG: Replace fuse.

  7. CHECK FUEL PUMP POWER SUPPLY CURCUIT-IV 
    1. Disconnect IPDM E/R harness connector E119.
    2. Check harness continuity between "fuel level sensor unit and fuel pump" terminal 1 and IPDM E/R terminal 13.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG 

    OK: GO TO  12.

    NG: GO TO 8.

  8. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors C1, E41
    • Harness for open or short between "fuel level sensor unit and fuel pump" and IPDM E/R

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

  9. CHECK FUEL PUMP GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between "fuel level sensor unit and fuel pump" terminal 3 and ground.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    2. Also check harness for short to ground.

    OK or NG 

    OK: GO TO  11.

    NG: GO TO 10.

  10. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors C1, E41
    • Harness for open or short between "fuel level sensor unit and fuel pump" and ground

    : Repair open circuit or short to power in harness or connectors.

  11. CHECK FUEL PUMP 

    Refer to "COMPONENT INSPECTION "

    OK or NG 

    OK: GO TO 12.

    NG: Replace fuel pump.

  12. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT "

    OK or NG 

    OK: Replace IPDM E/R.

    NG: Repair or replace harness or connectors.