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Home >> Infiniti >> 2012 >> G25 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P0443 To P1084 >> DTC P0451: EVAP Control System Pressure Sensor >> DTC Logic >> DTC Confirmation Procedure
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DTC Confirmation Procedure

NOTE: Never remove fuel filler cap during DTC confirmation procedure.
  1. PRECONDITIONING

    If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.

    1. Turn ignition switch OFF and wait at least 10 seconds.
    2. Turn ignition switch ON.
    3. Turn ignition switch OFF and wait at least 10 seconds.

      With CONSULT: GO TO 2.

      Without CONSULT: GO TO  5.

  2. PERFORM DTC CONFIRMATION PROCEDURE
    1. Start engine and wait at least 40 seconds.
      NOTE: Do not depress accelerator pedal even slightly.
    2. Check 1st trip DTC.

      Is 1st trip DTC detected? 

      YES: Go to "DIAGNOSIS PROCEDURE ".

      NO: GO TO 3.

  3. PERFORM DTC CONFIRMATION PROCEDURE-2

    With CONSULT 

    1. Select "EVAP DIAG READY" in "DATA MONITOR" mode of "ENGINE".
    2. Let it idle until "OFF" of "EVAP DIAG READY" changes to "ON".
      NOTE: It will take at most 2 hours until "OFF" of "EVAP DIAG READY" changes to "ON".
    3. Turn ignition switch OFF and wait at least 90 minutes.
      NOTE: Never turn ignition switch ON during 90 minutes.
    4. Turn ignition switch ON.
    5. Select "EVAP LEAK DIAG" in "DATA MONITOR" mode of "ENGINE".
    6. Check that "EVAP LEAK DIAG" indication.

      Which is displayed on CONSULT? 

      CMPLT: GO TO 4.

      YET:

      1. Perform DTC CONFIRMATION PROCEDURE again.
      2. GO TO  1.
  4. PERFORM DTC CONFIRMATION PROCEDURE-3

    With CONSULT 

    Check 1st trip DTC.

    Is 1st trip DTC detected? 

    YES: Proceed to "DIAGNOSIS PROCEDURE ".

    NO: INSPECTION END

  5. PERFORM DTC CONFIRMATION PROCEDURE-4

    With GST 

    1. Start engine and let it idle for least 40 seconds.
      NOTE: Do not depress accelerator pedal even slightly.
    2. Check 1st trip DTC.

      Is 1st trip DTC detected? 

      YES: Proceed to "DIAGNOSIS PROCEDURE ".

      NO: GO TO 6.

  6. PERFORM DTC CONFIRMATION PROCEDURE-5

    With GST 

    1. Let it idle for at least 2 hours.
    2. Turn ignition switch OFF and wait at least 90 minutes.
      NOTE: Never turn ignition switch ON during 90 minutes.
    3. Turn ignition switch ON.
    4. Check 1st trip DTC.

      Is 1st trip DTC detected? 

      YES: Proceed to "DIAGNOSIS PROCEDURE ".

      NO: INSPECTION END