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Diagnostic Procedure

WARNING: This page is about a different car, the 2008 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECTION START 

    Turn ignition switch to START.

    Is any cylinder ignited? 

    Yes or No 

    Yes (With CONSULT-III) >> GO TO 2.

    Yes (Without CONSULT-III) >> GO TO  3.

    No: GO TO  7.

  2. CHECK OVERALL FUNCTION 

    With CONSULT-III 

    1. Start engine.
    2. Perform "POWER BALANCE" in "ACTIVE TEST" mode with CONSULT-III.
    3. Make sure that each circuit produces a momentary engine speed drop.

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO  7.

  3. CHECK FUNCTION OF FUEL INJECTOR-I 

    Without CONSULT-III 

    1. Stop engine.
    2. Disconnect harness connector F44 (2), F101 (3).
    3. Turn ignition switch ON.
      • <==: Vehicle front
      • Intake manifold collector (1)
        Fig 1: Identifying F44, F101 Harness Connector And Intake Manifold Collector
        G04905406Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between harness connector F44 terminal 5 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

    5. Turn ignition switch OFF.
    6. Disconnect ECM harness connector.
    7. Check harness continuity between harness connector F44 terminal and ECM terminal as follows.

      Refer to WIRING DIAGRAM .

      Fig 2: Checking Voltage Between Harness Connector F44 Terminal 5 And Ground
      G04905407Courtesy of NISSAN MOTOR CO., U.S.A.
      CONNECTOR TERMINAL VOLTAGE SPECIFICATION

      Cylinder Harness connector F44 terminal ECM terminal
      1 6 23
      3 2 22
      5 1 21

      Continuity should exist. 

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

    OK or NG 

    OK: GO TO  5.

    NG: GO TO 4.

  4. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E8, F17
    • Fuse block (J/B) connector E30
    • 10A fuse
    • Harness for open or short between harness connector F44 and fuse
    • Harness for open or short between harness connector F44 and ECM

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

  5. CHECK FUNCTION OF FUEL INJECTOR-II 

    Provide battery voltage between harness connector F101 as follows and then interrupt it. Listen to each fuel injector operating sound.

    CONNECTOR TERMINAL VOLTAGE SPECIFICATION

    Cylinder Harness connector F101 terminal
    (+) (-)
    1 5 6
    3 5 2
    5 5 1

    Operating sound should exist. 

    OK or NG 

    OK: GO TO 6.

    NG: GO TO  7.

    Fig 3: Applying Battery Voltage Between Harness Connector F101
    G04905408Courtesy of NISSAN MOTOR CO., U.S.A.
  6. CHECK FUNCTION OF FUEL INJECTOR-III 
    1. Reconnect all harness connector disconnected.
    2. Start engine.
    3. Listen to fuel injectors No. 2, No. 4, No. 6 operating sound.

      Clicking noise should exist. 

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO 7.

    Fig 4: Checking Fuel Injector
    G04900354Courtesy of NISSAN MOTOR CO., U.S.A.
  7. CHECK FUEL INJECTOR POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect fuel injector harness connector.
      Fig 5: Identifying Fuel Injector Harness Connector
      G04905853Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Turn ignition switch ON.
    4. Check voltage between fuel injector terminal 1 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  9.

    NG: GO TO 8.

    Fig 6: Checking Voltage Between Fuel Injector Terminal 1 And Ground
    G04900780Courtesy of NISSAN MOTOR CO., U.S.A.
  8. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E8, F17
    • Harness connectors F44, F101
    • Fuse block (J/B) connector E30
    • 10A fuse
    • Harness for open or short between fuel injector and fuse

    : Repair harness or connectors.

  9. CHECK FUEL INJECTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between fuel injector terminal 2 and ECM terminals 21, 22, 23, 40, 41, 42. 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 F101, F44
    • Harness for open or short between fuel injector and ECM

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

  11. CHECK FUEL INJECTOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 12.

    NG: Replace fuel injector.

  12. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    : INSPECTION END 

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