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Diagnostic Procedure

WARNING: This page is about a different car, the 2007 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK OVERALL FUNCTION 

    With CONSULT-II 

    1. Start engine and warm it up to normal operating temperature.
    2. Perform "VIAS SOL VALVE" in "ACTIVE TEST" mode with CONSULT-II.
    3. Turn VIAS control solenoid valve ON and OFF, and make sure that power valve actuator rod moves as shown in the figure.
      NOTE: Use an inspection mirror (A) to confirm the operation of power valve actuator rod.
      Fig 1: CONSULT-II Display - ACTIVE TEST
      G04905895Courtesy of NISSAN NORTH AMERICA, INC.

    Without CONSULT-II 

    1. Start engine and warm it up to normal operating temperature.
    2. Rev engine up to between 1, 800 and 3, 600 rpm and make sure that power valve actuator rod moves as shown in the figure.
      NOTE: Use an inspection mirror (A) to confirm the operation of power valve actuator rod.
      • <==: Vehicle front
      • Power valve actuator (1)

    OK or NG 

    OK: INSPECTION END 

    NG (With CONSULT-II) >> GO TO 2.

    NG (Without CONSULT-II) >> GO TO  3.

    Fig 2: Identifying Power Valve Actuator Rod
    G04905896Courtesy of NISSAN NORTH AMERICA, INC.
  2. CHECK VACUUM EXISTENCE 

    With CONSULT-II 

    1. Stop engine and disconnect vacuum hose connected to power valve actuator.
    2. Install the vacuum gauge as shown in the figure.
    3. Start engine and let it idle.
    4. Perform "VIAS SOL VALVE" in "ACTIVE TEST" mode with CONSULT-II.
    5. Turn VIAS control solenoid valve ON and OFF, and check vacuum existence under the following conditions.
      Fig 3: CONSULT-II Display - ACTIVE TEST
      G04905897Courtesy of NISSAN NORTH AMERICA, INC.
      VIAS SOL VALVE

      VIAS SOL VALVE Vacuum
      ON Should exist
      OFF Should not exist

    OK or NG 

    OK: Repair or replace power valve actuator.

    NG: GO TO  4.

  3. CHECK VACUUM EXISTENCE 

    Without CONSULT-II 

    1. Stop engine and disconnect vacuum hose connected to power valve actuator.
    2. Install the vacuum gauge as shown in the figure.
    3. Disconnect VIAS control solenoid valve harness connector.
    4. Start engine and let it idle.
    5. Apply 12V of direct current between VIAS control solenoid valve terminals 1 and 2.
      Fig 4: Applying 12V Of Direct Current Between VIAS Control Solenoid Valve Terminals 1 And 2
      G04905898Courtesy of NISSAN NORTH AMERICA, INC.
    6. Check vacuum existence under the following conditions.
      CONNECTOR TERMINAL VOLTAGE SPECIFICATION

      Condition Vacuum
      12V direct current supply Should exist
      No supply Should not exist

    OK or NG 

    OK: Repair or replace power valve actuator.

    NG: GO TO 4.

  4. CHECK VACUUM HOSE 
    1. Stop engine.
    2. Check hoses and tubes between intake manifold and power valve actuator for crack, clogging, improper connection or disconnection. Refer to "VACUUM HOSE DRAWING ".

    OK or NG 

    OK: GO TO 5.

    NG: Repair hoses or tubes.

    Fig 5: Checking Hoses And Tubes
    G04897448Courtesy of NISSAN NORTH AMERICA, INC.
  5. CHECK VACUUM TANK 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 6.

    NG: Replace vacuum tank.

  6. CHECK VIAS CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect VIAS control solenoid valve (2) harness connector.
    3. Turn ignition switch ON.
      • <==: Vehicle front
      • Power valve actuator (1)
        Fig 6: Identifying VIAS Control Solenoid Valve
        G04905737Courtesy of NISSAN NORTH AMERICA, INC.
    4. Check voltage between VIAS control solenoid valve terminal 1 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  8.

    NG: GO TO 7.

    Fig 7: Checking Voltage Between Terminal 1 And Ground
    G04897281Courtesy of NISSAN NORTH AMERICA, INC.
  7. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E5, F14
    • Harness for open or short between VIAS control solenoid valve and IPDM E/R
    • Harness for open or short between VIAS control solenoid valve and ECM

    : Repair harness or connectors.

  8. CHECK VIAS CONTROL SOLENOID VALVE OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between ECM terminal 29 and VIAS control solenoid valve terminal 2.

      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 9.

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

  9. CHECK VIAS CONTROL SOLENOID VALVE 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 10.

    NG: Replace VIAS control solenoid valve.

  10. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    : INSPECTION END 

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