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Home >> Infiniti >> 2008 >> M35 Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (VQ35DE) - Component And System Testing >> Fuel Pump >> Diagnostic Procedure
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Diagnostic Procedure

  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: Pinching Fuel Feed Hose
    G05216936Courtesy 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-III 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
    G04900786Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II 

    Check voltage between IPDM E/R terminal 40 and ground with CONSULT-III or tester.

    Voltage: Battery voltage 

    OK or NG 

    OK: GO TO 4.

    NG: GO TO  16.

    Fig 3: Checking Voltage Between IPDM E/R Terminal 40 And Ground
    G04915864Courtesy of NISSAN MOTOR CO., U.S.A.
  4. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E108, M15
    • Harness for open or short between IPDM E/R and ECM

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

  5. CHECK CONDENSER POWER SUPPLY CIRCUIT-I 
    1. Turn ignition switch OFF.
    2. Reconnect all harness connectors disconnected.
    3. Disconnect condenser harness connector.
    4. Turn ignition switch ON.
    5. Check voltage between condenser terminal 1 and ground with CONSULT-III or tester.

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

    OK or NG 

    OK: GO TO  9.

    NG: GO TO 6.

    Fig 4: Checking Voltage Between Condenser Terminal 1 And Ground
    G04875485Courtesy 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 CONDENSER POWER SUPPLY CIRCUIT-II 
    1. Disconnect IPDM E/R harness connector E8.
    2. Check harness continuity between IPDM E/R terminal 39 and condenser terminal 1.

      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  16.

    NG: GO TO 8.

  8. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E106, B4
    • Harness connectors B65, B434
    • IPDM E/R connector E8
    • Harness for open or short between IPDM E/R and condenser

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

  9. CHECK CONDENSER GROUND CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect dropping resistor harness connector.
      Fig 5: Identifying FPCM And Dropping Resistor
      G05210208Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check harness continuity between condenser terminal 2 and dropping resistor terminal 2.

      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  11.

    NG: GO TO 10.

  10. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors B65, B434.
    • Harness for open or short between condenser and dropping resistor.

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

  11. CHECK CONDENSER 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 12.

    NG: Replace condenser.

  12. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-III 
    1. Turn ignition switch OFF.
    2. Disconnect harness connectors B65, B434.
    3. Disconnect "fuel level sensor unit and fuel pump" harness connector (1).
      • Illustration shows the view with rear seat cushion and inspection hole cover (RH) removed.
      • ← : Vehicle front
        Fig 6: Identifying Fuel Level Sensor Unit And Fuel Pump Harness Connector
        G05209765Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check harness continuity between the following;

      harness connector B434 terminal 7 and "fuel level sensor unit and fuel pump" terminal 1,

      "fuel level sensor unit and fuel pump" terminal 3 and harness connector B434 terminal 16,

      harness connector B65 terminal 16 and dropping resistor terminal 2,

      Dropping resister terminal 1 and ground.

      Refer to WIRING DIAGRAM .

      Continuity should exist  .

    OK or NG 

    OK: GO TO  14.

    NG: GO TO 13.

  13. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors B65, B434
    • Harness for open or short between "fuel level sensor unit and fuel pump" and harness connector B434
    • Harness for open or short between "fuel level sensor unit and fuel pump" and dropping resistor
    • Harness for open or short between dropping resistor and ground

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

  14. CHECK DROPPING RESISTOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 15.

    NG: Replace dropping resistor.

  15. CHECK FUEL PUMP 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 16.

    NG: Replace fuel pump.

  16. 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.

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