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Home >> Infiniti >> 2019 >> QX50 Essential, FWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTC/Circuit Diagnosis) (1 Of 12) >> DTC/Circuit Diagnosis >> DTC P0016: Intake Valve Timing Control >> DTC Description >> DTC Confirmation Procedure
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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.

    TESTING CONDITION:

    Before performing the following procedure, confirm that battery voltage is between 11 V and 16 V at idle.

    GO TO 2.

  2. PERFORM DTC CONFIRMATION PROCEDURE-1 

    SYMBOL With CONSULT

    1. Turn ignition switch ON and select "DATA MONITOR" mode of "ENGINE" using CONSULT.
    2. Start engine and warm it up to normal operating temperature.
    3. Maintain the following conditions for at least 13consecutive seconds. Hold the accelerator pedal as steady as possible.

      ENG SPEED

      1, 200 - 2, 000 rpm

      COOLANT TEMP/S

      More than 60 deg.C (140 deg.F)

      Selector lever

      P or N position

    4. Stop vehicle with engine running and let engine idle for 13 seconds.
    5. Check 1st trip DTC.

    SYMBOL With GST

    Follow the procedure "With CONSULT" above.

    Is 1st trip DTC detected?

    YES

    Proceed to Diagnosis Procedure .

    NO

    GO TO 3.

  3. PERFORM DTC CONFIRMATION PROCEDURE-2 

    SYMBOL With CONSULT

    1. Maintain the following conditions for at least 20 consecutive seconds.

      ENG SPEED

      1, 200 - 2, 000 rpm

      COOLANT TEMP/S

      60 - 120 deg.C (140 - 248 deg.F)

      Selector lever

      D position

      Driving location

      Driving vehicle uphill

      (Increased engine load will help maintain the driving conditions required for this test.)

      CAUTION: Always drive at a safe speed.
    2. Check 1st trip DTC.

    SYMBOL With GST

    Follow the procedure "With CONSULT" above.

    Is 1st trip DTC detected?

    YES

    Proceed to Diagnosis Procedure .

    NO

    To check malfunction symptom before repair: Refer to Intermittent Incident .

    NO

    Confirmation after repair: INSPECTION END