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Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - 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: Displaying ACTIVE TEST With Mode Consult-II
      G00779548Courtesy 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.
      4. Fig 2: Ensuring Power Valve Actuator Rod Moves
      G00779549Courtesy 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: Ensuring Power Valve Actuator Rod Moves
    G00779550Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: INSPECTION END 
    2. NG (With CONSULT-II): GO TO 2.
    3. 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.
      5. Fig 4: Displaying ACTIVE TEST" With Mode Consult-II
      G00779552Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 5: VIAS Solenoid Valve Vacuum Table
      G00779551Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: Repair or replace power valve actuator.
    2. 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.
      6. Fig 6: Applying Current Between VIAS Control Solenoid Valve Terminals 1 & 2
      G00779554Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 7: Condition & Vacuum Table
      G00779553Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: Repair or replace power valve actuator.
    2. 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 8: Checking Hoses & Tubes
      G00779555Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 5.
    2. NG: Repair hoses or tubes.
  5. CHECK VACUUM TANK 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK: GO TO 6.
    2. NG: Replace vacuum tank.
  6. CHECK VIAS CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT-I 
    1. Turn ignition switch ON.
    2. Disconnect VIAS control solenoid valve harness connector.
    3. Turn ignition switch ON.
      Fig 9: Disconnecting VIAS Control Solenoid Valve Harness Connector
      G00779556Courtesy 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 

      5. Fig 10: Checking Voltage Between VIAS Control Solenoid Valve Terminal 1 & Ground
      G00779557Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO  8.
    2. NG: GO TO 7.
  7. CHECK VIAS CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT-II 
    1. Turn ignition switch OFF.
    2. Disconnect ECM relay.
    3. Check harness continuity between ECM relay terminal 7 and VIAS control solenoid valve terminal 1.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    4. Also check harness for short to ground and short to power.
      5. Fig 11: Disconnecting ECM Relay
      G00779558Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 8.
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
  8. CHECK VIAS CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT-III 

    Check voltage between ECM relay terminal 6 and ground with CONSULT-II or tester.

    Voltage: Battery voltage 

    Fig 12: Checking Voltage Between ECM Relay Terminal 6 & Ground
    G00779559Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO  10.
    2. NG: GO TO 9.
  9. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E10, F48
    • Fuse and fusible link box connector E22
    • 15A fuse
    • Harness for open or short between ECM relay and battery
      1. Repair or replace harness or connectors.
  10. CHECK ECM RELAY 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK: GO TO  13.
    2. NG: Replace ECM relay.
  11. 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 

    1. OK: GO TO 12.
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
  12. CHECK VIAS CONTROL SOLENOID VALVE 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK: GO TO 13.
    2. NG: Replace VIAS control solenoid valve.
  13. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    1. INSPECTION END 
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