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Diagnostic Procedure

WARNING: This page is about a different car, the 2004 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECTION START 

    which malfunction (A or B) is duplicated?

    A or B 

    1. A: GO TO  3 .
    2. B: GO TO 2.
  2. CHECK INTAKE SYSTEM 

    Check the following for connection.

    • Air duct
    • Vacuum hoses
    • Intake air passage between air duct and intake manifold

    OK or NG 

    1. OK: GO TO 3
    2. NG: Reconnect the parts.
  3. CHECK GROUND CONNECTIONS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten ground three screws on the body. Refer to GROUND INSPECTION  .
      Fig 1: Checking Ground Connections
      G00775310Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 4.
    2. NG: Repair or replace ground connections.
  4. CHECK MAF SENSOR POWER SUPPLY CIRCUIT 
    1. Disconnect mass air flow (MAF) sensor harness connector.
    2. Turn ignition switch ON.
      Fig 2: Disconnecting Mass Air Flow (MAF) Sensor Harness Connector
      G00775311Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between MAF sensor terminal 5 and ground with CONSULT-II or tester.
      Fig 3: Checking Voltage Between MAF Sensor And Ground
      G00775312Courtesy of NISSAN MOTOR CO., U.S.A.
      1. Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  6 .
    2. NG: GO TO 5.
  5. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E5, F14
    • Harness for open or short between IPDM E/R and mass air flow sensor
    • Harness for open or short between mass air flow sensor and ECM
      1. : Repair harness or connectors.
  6. CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect TCM harness connector.
    4. Check harness continuity between MAF sensor terminal 4 and ECM terminal 67, TCM terminal 42. Refer to WIRING DIAGRAM  .
      1. Continuity should exist. 
    5. Also check harness for short to ground or short to power.

    OK or NG 

    1. OK: GO TO  8 .
    2. NG: GO TO 7.
  7. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E19, F33
    • Harness for open or short between mass air flow sensor and ECM
    • Harness for open or short between mass air flow sensor and TCM
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  8. CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between MAF sensor terminal 3 and ECM terminal 51.

      Refer to WIRING DIAGRAM  .

      1. Continuity should exist. 
    2. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO 9.
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
  9. CHECK MASS AIR FLOW SENSOR 

    Refer to COMPONENT INSPECTION  .

    OK or NG 

    1. OK: GO TO 10.
    2. NG: Replace mass air flow sensor.
  10. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

    1. INSPECTION END