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Home >> Nissan-Datsun >> 2006 >> Altima Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing (Qr25DE) >> VIAS >> Diagnostic Procedure
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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: CONSULT-II Display - ACTIVE TEST
      G04166732Courtesy 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: Turning VIAS Control Solenoid Valve On And Off
      G04166733Courtesy 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: Identifying Power Valve Actuator Rod Moves
      G04166734Courtesy 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 SOL VALVE CHART

      VIAS SOL VALVE Vacuum
      ON Should exist.
      OFF Should not exist.
      Fig 4: CONSULT-II Display - ACTIVE TEST
      G04166735Courtesy 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.
      VACUUM CONDITION CHART

      Condition Vacuum
      12V direct current supply Should exist.
      No supply Should not exist.
      Fig 5: Applying 12V Of Direct Current Between Vias Control Solenoid Valve Terminals 1 And 2
      G04166736Courtesy of NISSAN MOTOR CO., U.S.A.

    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 ".
    Fig 6: Checking Hoses And Tubes
    G04166737Courtesy 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 harness connector.
    3. Turn ignition switch ON.
      Fig 7: Identifying VIAS Control Solenoid Valve Harness Connector
      G04166738Courtesy 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 

    Fig 8: Checking Voltage Between Terminal 1 And Ground
    G04148503Courtesy 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 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