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Diagnostic Procedure

WARNING: This page is about a different car, the 2008 Nissan Maxima. 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  .

    3. Fig 1: Pinching Fuel Feed Hose With Two Fingers
      G04915862Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO  2.

  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 

    5. Fig 2: Checking Voltage Between ECM Terminal 113 And Ground
      G04900786Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  5.

    NG: GO TO  3.

  3. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I 

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

    Voltage: Battery voltage 

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

    OK or NG 

    OK: GO TO  4.

    NG: GO TO  14.

  4. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E131, M92
    • Harness for open or short between IPDM E/R and ECM
    • >> Repair harness or connectors.

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

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

    6. Fig 4: Checking Voltage Between Condenser-1 Terminal 1 And Ground
      G04875485Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  9.

    NG: GO TO  6.

  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-1 POWER SUPPLY CIRCUIT-II 
    1. Disconnect IPDM E/R harness connector E124.
    2. Check harness continuity between IPDM E/R terminal 39 and condenser-1 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  14.

    NG: GO TO  8.

  8. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E131, M92
    • Harness connectors M11, B1
    • Harness for open or short between IPDM E/R and condenser-1
    • >> Repair harness or connectors.

  9. CHECK CONDENSER-1 GROUND CIRCUIT 
    1. Check harness continuity between condenser-1 terminal 2 and ground.

      Refer to Wiring Diagram.

      Continuity should exist  .

    2. Also check harness for short to power.

    OK or NG 

    OK: GO TO  10.

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

  10. CHECK CONDENSER-1 

    Refer to "COMPONENT INSPECTION ."

    OK or NG 

    OK: GO TO  11.

    NG: Replace condenser-1.

  11. CHECK FUEL PUMP POWER SUPPLY AND GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect harness connectors M11, B1.
    3. Disconnect "fuel level sensor unit and fuel pump" harness connector.
    4. Check harness continuity between "fuel level sensor unit and fuel pump" terminal 1 and harness connector B1 terminal 15, "fuel level sensor unit and fuel pump" terminal 3 and ground. Refer to Wiring Diagram.

      Continuity should exist  .

    5. Also check harness for short to ground and short to power.
    6. Fig 5: Identifying Fuel Level Sensor Unit And Fuel Pump Harness Connector
      G04915485Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  13.

    NG: GO TO  12.

  12. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness for open or short between "fuel level sensor unit and fuel pump" and harness connector B1
    • Harness for open or short between "fuel level sensor unit and fuel pump" and ground
    • >> Repair open circuit or short to ground or short to power in harness or connectors.

  13. CHECK FUEL PUPMP 

    Refer to "COMPONENT INSPECTION ."

    OK or NG 

    OK: GO TO  14.

    NG: Replace fuel level sensor unit and fuel pump.

  14. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ."

    OK or NG 

    OK: Replace IPDM E/R. Refer to "IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM) ."

    NG: Repair or replace harness or connectors.