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Home › Infiniti › 2004 › QX56 AWD › Repair and Diagnosis › Engine Performance › System › Engine Control System › DTC P1444: EVAP Canister Purge Volume Control Solenoid Valve › Diagnostic Procedure

Diagnostic Procedure

  1. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect EVAP canister purge volume control solenoid valve harness connector.
    3. Turn ignition switch ON.
      Fig 1: DTC P1444 Locating EVAP Canister Purge Volume Control Solenoid Valve & EVAP Service Port
      G02691791Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between EVAP canister purge volume control solenoid valve terminal 1 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG

    OK: GO TO  3.

    NG: GO TO 2.

    Fig 2: DTC P1444 Checking Voltage Between EVAP Canister Purge Volume Control Solenoid Valve Terminal 1 & Ground
    G02691792Courtesy of NISSAN MOTOR CO., U.S.A.
  2. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E2, F32
    • IPDM E/R harness connector E119
    • Harness for open or short between EVAP canister purge volume control solenoid valve and IPDM E/R
    • Harness for open or short between EVAP canister purge volume control solenoid valve and ECM

      : Repair harness or connectors.

  3. CHECK EVAP CANISTER PURGE VOLUME 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 45 and EVAP canister purge volume 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 4.

    NG: Repair open circuit or short to ground or short to power in harness or connectors.

  4. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR 
    1. Disconnect EVAP control system pressure sensor harness connector.
    2. Check connectors for water.

      Water should not exist. 

    OK or NG

    OK: GO TO 5.

    NG: Replace EVAP control system pressure sensor.

  5. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR 

    Refer to COMPONENT INSPECTION .

    OK or NG

    OK (With CONSULT-II): GO TO 6.

    OK (Without CONSULT-II): GO TO  7.

    NG: Replace EVAP control system pressure sensor.

  6. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE 

    WITH CONSULT-II 

    1. Turn ignition switch OFF.
    2. Reconnect all harness connectors disconnected.
    3. Start engine.
    4. Perform "PURG VOL CONT/V" in "ACTIVE TEST" mode with CONSULT-II. Check that engine speed varies according to the valve opening.

    OK or NG

    OK: GO TO  8.

    NG: GO TO 7.

    Fig 3: DTC P1444 Perform "PURG VOL CONT/V" In "ACTIVE TEST" Mode With CONSULT-II
    G02691793Courtesy of NISSAN MOTOR CO., U.S.A.
  7. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE 

    Refer to COMPONENT INSPECTION .

    OK or NG

    OK: GO TO 8.

    NG: Replace EVAP canister purge volume control solenoid valve.

  8. CHECK RUBBER TUBE FOR CLOGGING 
    1. Disconnect rubber tube connected to EVAP canister vent control valve.
    2. Check the rubber tube for clogging.

    OK or NG

    OK: GO TO 9.

    NG: Clean the rubber tube using an air blower.

  9. CHECK EVAP CANISTER VENT CONTROL VALVE 

    Refer to COMPONENT INSPECTION .

    OK or NG

    OK: GO TO 10.

    NG: Replace EVAP canister vent control valve.

  10. CHECK IF EVAP CANISTER SATURATED WITH WATER 
    1. Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor attached.
    2. Check if water will drain from the EVAP canister.

    Yes or No

    Yes: GO TO 11.

    No: GO TO  13.

    Fig 4: Locating EVAP Canister & EVAP Canister Vent Control Valve
    G02691794Courtesy of NISSAN MOTOR CO., U.S.A.
  11. CHECK EVAP CANISTER 

    Weigh the EVAP canister with the EVAP canister vent control valve and EVAP control system pressure sensor attached.

    The weight should be less than 2.2 kg (4.9 lb). 

    OK or NG

    OK: GO TO  13.

    NG: GO TO 12.

  12. DETECT MALFUNCTIONING PART 

    Check the following.

    • EVAP canister for damage
    • EVAP hose between EVAP canister and vehicle frame for clogging or poor connection

      : Repair hose or replace EVAP canister.

  13. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

    : INSPECTION END 

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