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Home >> Infiniti >> 2004 >> Q45 >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> DTC P1448: EVAP Canister Vent Control Valve >> DTC Confirmation Procedure
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DTC Confirmation Procedure

NOTE:
  • If DTC P1448 is displayed with P0442, P0455, P0456, P1442 or P1456, first perform trouble diagnosis for DTC P1448.
  • If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.

With CONSULT-II 

TESTING CONDITION: 

  1. Turn ignition switch ON.
  2. Turn ignition switch OFF and wait at least 10 seconds.
  3. Turn ignition switch ON and select "DATA MONITOR" mode with CONSULT-II.
  4. Make sure that the following conditions are met.
    Fig 1: Testing Conditions
    G00761156Courtesy of NISSAN MOTOR CO., U.S.A.
  5. Select "EVAP SML LEAK P0442/P1442" of "EVAPORATIVE SYSTEM" in "DTC WORK SUPPORT" mode with CONSULT-II. Follow the instruction displayed.
    Fig 2: View Of CONSULT-II Screens
    G00761158Courtesy of NISSAN MOTOR CO., U.S.A.

    If the engine speed cannot be maintained within the range displayed on the CONSULT-II screen, go to BASIC INSPECTION  .

  6. Make sure that "OK" is displayed.

    If "NG" is displayed, go to the following step.

    NOTE: Make sure that EVAP hoses are connected to EVAP canister purge volume control solenoid valve properly.
  7. Stop engine and wait at least 10 seconds, then turn ON.
  8. Disconnect hose from water separator.
  9. Select "VENT CONTROL/V" of "ACTIVE TEST" mode with CONSULT-II.
  10. Touch "ON" and "OFF" alternately.
  11. Make sure the following.
    Fig 3: Checking Air Passage Continuity
    G00761160Courtesy of NISSAN MOTOR CO., U.S.A.

    If the result is NG, go to DIAGNOSTIC PROCEDURE  .

    If the result is OK, go to "Diagnostic Procedure" for DTC P0442, DIAGNOSTIC PROCEDURE  .