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Home >> Infiniti >> 2008 >> M45 Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (VK45DE) - Component And System Troubleshooting >> VIAS >> Diagnostic Procedure
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Diagnostic Procedure

  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 (1) rod moves.
      Fig 1: Identifying Power Valve Actuator
      G05211183Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-III 

    1. Lift up the vehicle.
    2. Start engine and warm it up to normal operating temperature.
    3. Make sure that power valve actuator (1) rod moves when changing the gear position to N and D alternately.
      Fig 2: Identifying Power Valve Actuator
      G05211183Courtesy 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. Start engine and let it idle.
    3. Perform "VIAS SOL VALVE" in "ACTIVE TEST" mode with CONSULT-III.
    4. Turn VIAS control solenoid valve ON and OFF, and check vacuum existence under the following conditions.
      VACUUM EXISTENCE CONDITIONS

      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. Disconnect VIAS control solenoid valve (1) harness connector.
      • <=: Vehicle front
    3. Start engine and let it idle.
      Fig 3: Identifying VIAS Control Solenoid Valve Harness Connector
      G05211008Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Apply 12V of direct current between VIAS control solenoid valve terminals 1 and 2.
    5. Check vacuum existence under the following conditions.
      VACUUM EXISTENCE CONDITIONS

      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.

    Fig 4: Applying Direct Current Between VIAS Control Solenoid Valve Terminals 1 And 2
    G04897447Courtesy of NISSAN MOTOR CO., U.S.A.
  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 MOTOR CO., U.S.A.
  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 (1) harness connector.
      • <=: Vehicle front
    3. Turn ignition switch ON.
      Fig 6: Identifying VIAS Control Solenoid Valve Harness Connector
      G05211008Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between terminal 1 and ground with CONSULT-III 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 MOTOR CO., U.S.A.
  7. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E12, F3
    • Harness continuity between IPDM E/R and VIAS control solenoid valve

      >> Repair open circuit or short to ground or short to power in 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