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Home >> Infiniti >> 2004 >> Q45 >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> DTC P1491: Vacuum Cut Valve Bypass Valve >> DTC Confirmation Procedure
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DTC Confirmation Procedure

CAUTION: Always drive vehicle at a safe speed.
NOTE: If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.

TESTING CONDITION: 

With CONSULT-II 

  1. Turn ignition switch ON.
  2. Start engine and warm it up to normal operating temperature.
  3. Turn ignition switch OFF and wait at least 10 seconds.
  4. Start engine and let it idle for at least 70 seconds.
  5. Select "VC CUT/V BP/V P1491" of "EVAPORATIVE SYSTEM" in "DTC WORK SUPPORT" mode with CONSULT-II.
  6. Touch "START".
  7. When the following conditions are met, "TESTING" will be displayed on the CONSULT-II screen. Maintain the conditions continuously until "TESTING" changes to "COMPLETED". (It will take at least 30 seconds.)
    Fig 1: Testing Conditions
    G00761225Courtesy of NISSAN MOTOR CO., U.S.A.

    If "TESTING" is not displayed after 5 minutes, retry from step 3. 

  8. Make sure that "OK" is displayed after touching "SELF-DIAG RESULTS". If "NG" is displayed, refer to DIAGNOSTIC PROCEDURE  .