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Diagnostic Procedure

  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.
      Fig 1: Display Active Test Mode Screen
      G02527027Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Turn VIAS control solenoid valve ON and OFF, and make sure that power valve actuator rod moves.
      Fig 2: Checking Power Valve Actuator Rod Movement (With CONSULT-II)
      G02527028Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-II 

    1. Start engine and warm it up to normal operating temperature.
    2. Rev engine quickly up to above 5,000 RPM and make sure that power valve actuator rod moves.
      Fig 3: Checking Power Valve Actuator Rod Movement (Without CONSULT-II)
      G02527029Courtesy of NISSAN MOTOR CO., U.S.A.

      OK or NG

      • OK: INSPECTION END 
      • NG (With CONSULT-II): GO TO 2.
      • NG (Without CONSULT-II): GO TO 3.
  2. CHECK VACUUM EXISTENCE 

    With CONSULT-II 

    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-II.
    4. Turn VIAS control solenoid valve ON and OFF, and check vacuum existence under the following conditions.
      VIAS SOLENOID VALVE AND VACUUM REFERENCE

      VIAS SOL VALVE Vacuum
      ON Should exist.
      OFF Should not exist.
      Fig 4: Display Active Test Mode Screen
      G02527030Courtesy of NISSAN MOTOR CO., U.S.A.

      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. Disconnect VIAS control solenoid valve harness connector.
    3. Start engine and let it idle.
    4. Apply 12V of direct current between VIAS control solenoid valve terminals 1 and 2.
    5. Check vacuum existence under the following conditions.
      CONDITION AND VACUUM REFERENCE

      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 5: Applying 12V Of Direct Current Between VIAS Control Solenoid Valve Terminals 1 And 2
      G02527031Courtesy 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 6: Checking Hoses And Tubes Between Intake Manifold And Power Valve Actuator For Crack And Clogging
      G02527032Courtesy 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 harness connector.
    3. Turn ignition switch ON.
      Fig 7: Identifying VIAS Control Solenoid Valve And Intake Manifold Collector
      G02527033Courtesy of NISSAN MOTOR CO., U.S.A.
    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 8: Checking Voltage Between VIAS Control Solenoid Valve Terminal 1 And Ground
      G02527034Courtesy of NISSAN MOTOR CO., U.S.A.
  7. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E20, F32
    • IPDM E/R connector E122
    • 10A fuse
    • Harness continuity between fuse and VIAS control solenoid valve

      : 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