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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. CHECK EXHAUST SYSTEM 
    1. Start engine.
    2. Check exhaust pipes and muffler for leaks.
      Fig 1: Checking Exhaust Pipes And Muffler For Leaks
      G00775727Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 2.
    2. NG: Repair or replace exhaust system.
  2. CHECK EGR VOLUME CONTROL VALVE POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect EGR volume control valve harness connector.
    3. Turn ignition switch ON.
      Fig 2: Checking EGR Volume Control Valve Power Supply Circuit
      G00775728Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between EGR volume control valve terminals 2, 5 and ground with CONSULT-II or tester.
      Fig 3: Checking Voltage Between EGR Terminals 2, 5 And Ground
      G00775729Courtesy of NISSAN MOTOR CO., U.S.A.
      1. Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  4 .
    2. NG: GO TO 3.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E5, F14
    • IPDM E/R harness connector E122
    • Harness for open or short between EGR volume control valve and IPDM E/R
      1. Repair harness or connectors.
  4. CHECK EGR VOLUME CONTROL VALVE OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between ECM terminals and EGR volume control valve terminals as follows.

      Refer to WIRING DIAGRAM  .

      Fig 4: ECM Terminals And EGR Volume Control Valve Terminals Chart
      G00775730Courtesy of NISSAN MOTOR CO., U.S.A.
      1. Continuity should exist. 
    4. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO 5.
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
  1. 5. CHECK EGR PASSAGE 

    Check EGR passage for clogging and cracks.

    OK or NG 

    1. OK: GO TO 6.
    2. NG: Repair or replace EGR passage.
  2. 6. CHECK EGR VOLUME CONTROL VALVE 

    Refer to COMPONENT INSPECTION  .

    OK or NG 

    1. OK: GO TO 7.
    2. NG: Replace EGR volume control valve.
  3. 7. CHECK EGR TEMPERATURE SENSOR AND CIRCUIT 

    perform DTC Confirmation Procedure for DTC P 0405, P0406. Refer to DTC CONFIRMATION PROCEDURE  .

    OK or NG 

    1. OK: GO TO 8.
    2. NG: Repair or replace malfunctioning part.
  4. 8. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

    1. INSPECTION END 
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