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Diagnostic Procedure

WARNING: This page is about a different car, the 2008 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK OVERALL FUNCTION 

    With CONSULT-III 

    1. Start engine and warm it up to normal operating temperature.
    2. Perform "VIAS SOL VALVE" in "ACTIVE TEST" mode with CONSULT-III.
    3. Turn VIAS control solenoid valve ON and OFF and make sure that power valve actuator rod moves.
      Fig 1: Identifying Power Valve Actuator Rod
      G04915901Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-III 

    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 (2) moves as shown in the figure.
      • Power valve actuator (1)
      3. Fig 2: Identifying Power Valve Actuator Rod
      G04915901Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: INSPECTION END 

    NG (With CONSULT-III): GO TO  2.

    NG (Without CONSULT-III): GO TO  3.

  2. CHECK VACUUM EXISTENCE 

    With CONSULT-III 

    1. Stop engine and disconnect vacuum hose connected to power valve actuator.
    2. Install the vacuum gauge as shown in Fig 3.
    3. Start engine and let it idle.
    4. Perform "VIAS SOL VALVE" in "ACTIVE TEST" mode with CONSULT-III.
    5. Turn VIAS control solenoid valve ON and OFF, and check vacuum existence under the following conditions.
      Fig 3: CONSULT-III Display - Active Test
      G04915902Courtesy of NISSAN MOTOR CO., U.S.A.
      VIAS SOL VALVE SPECIFICATION

      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-III 

    1. Stop engine and disconnect vacuum hose connected to power valve actuator.
    2. Install the vacuum gauge as shown in Fig 4.
    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: Identifying Power Valve Actuator And VIAS Control Solenoid Valve
      G04915903Courtesy of NISSAN MOTOR CO., U.S.A.
    6. Check vacuum existence under the following conditions.
      VACUUM CONDITIONS CHART

      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 ."
      3. Fig 5: Checking Hoses And Tubes Between Intake Manifold And Power Valve Actuator
      G04897448Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  5.

    NG: Repair hoses or tubes.

  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.
      • Power valve actuator (1)
    3. Turn ignition switch ON.
      Fig 6: Identifying VIAS Control Solenoid Valve And Power Valve Actuator
      G04915743Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between terminal 1 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

      5. Fig 7: Checking Voltage Between Terminal 1 And Ground With CONSULT-III Or Tester
      G04897281Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  8.

    NG: GO TO  7.

  7. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E131, M92
    • Harness connectors M70, F58
    • 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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