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Diagnostic Procedure

WARNING: This page is about a different car, the 2005 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 System
      G02474043Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: GO TO 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. Fig 2: Disconnecting EGR Volume Control Valve Harness Connector
      G02474044Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Turn ignition switch ON.
    4. Check voltage between EGR volume control valve terminals 2, 5 and ground with CONSULT-II or tester.
      • Voltage: Battery voltage 

    OK or NG

    • OK: GO TO  4.
    • NG: GO TO 3.
      Fig 3: Checking Voltage Between EGR Volume Control Valve Terminals 2, 5 & Ground
      G02474045Courtesy of NISSAN MOTOR CO., U.S.A.
  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
    • : 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 .
      ECM AND EGR VOLUME CONTROL VALVE TERMINALS CONNECTION TABLE

      ECM terminal EGR volume control valve
      17 6
      18 3
      19 4
      20 1
      • Continuity should exist. 
    4. Also check harness for short to ground and short to power.

    OK or NG

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

    Check EGR passage for clogging and cracks.

    OK or NG

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

    Refer to "COMPONENT INSPECTION ".

    OK or NG

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

    Perform DTC Confirmation Procedure for DTC P0405, P0406. Refer to "DTC CONFIRMATION PROCEDURE ".

    OK or NG

    • OK: GO TO 8.
    • NG: Repair or replace malfunctioning part.
  8. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    • : INSPECTION END 
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