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Home >> Infiniti >> 2003 >> G35 2D Coupe, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls System - Component Testing - Coupe >> Fuel Pump Circuit >> 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 

    1. OK: INSPECTION END
    2. NG: GO TO 2.
      Fig 1: Pinching Fuel Feed Hose
      G03583540Courtesy 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 

    1. OK: GO TO  5.
    2. NG: GO TO 3.
      Fig 2: Checking Voltage Between ECM Terminal 113 And Ground
      G03583541Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I 
    1. Turn ignition switch ON.
    2. Check voltage between IPDM E/R terminal 20 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO 4.
    2. NG: GO TO  12.
      Fig 3: Checking Voltage Between IPDM E/R Terminal 20 And Ground
      G03583542Courtesy of NISSAN MOTOR CO., U.S.A.
  4. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E11, F2
    • Harness for open or short between IPDM E/R and ECM
    1. : Repair 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-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 

    1. OK: GO TO  9.
    2. NG: GO TO 6.
      Fig 4: Checking Voltage Between Condenser Terminal 1 And Ground
      G03583543Courtesy 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 

    1. OK: GO TO 7.
    2. NG: Replace fuse.
  7. CHECK CONDENSER POWER SUPPLY CIRCUIT-II 
    1. Disconnect IPDM E/R harness connector E7.
    2. Check harness continuity between IPDM E/R terminal 23 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 

    1. OK: GO TO  12.
    2. NG: GO TO 8.
  8. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E123, B41
    • Harness for open or short between IPDM E/R and condenser
    1. : Repair harness or connectors.
  9. CHECK CONDENSER GROUND CIRCUIT 
    1. Check harness continuity between condenser terminal 2 and ground. Refer to WIRING DIAGRAM .

      Continuity should exist. 

    2. Also check harness for short to power.

    OK or NG 

    1. OK: GO TO 10.
    2. NG: Repair open circuit or short to power in harness or connectors.
  10. CHECK CONDENSER 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK: GO TO 11.
    2. NG: Replace condenser.
  11. CHECK FUEL PUMP POWER SUPPLY AND GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect "fuel level sensor unit and fuel pump" harness connector.
    3. Check harness continuity between " fuel level sensor unit and fuel pump" terminal 1 and harness connector B41 terminal 3"fuel level sensor unit and fuel pump" terminal 3 and ground. Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG 

    1. OK: GO TO 12.
    2. NG: Repair open circuit or short to power in harness or connectors.
      Fig 5: Locating Fuel Level Sensor Unit And Fuel Pump
      G03583544Courtesy of NISSAN MOTOR CO., U.S.A.
  12. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    OK or NG 

    1. OK: Replace IPDM E/R.
    2. NG: Repair or replace harness or connectors.