DTC Confirmation Procedure

2019 Infiniti Q70 3.7 Luxe, AWDSECTION 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.

    GO TO 2.

  2. PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A 
    1. Start engine and warm it up to the normal operating temperature.
    2. Turn ignition switch OFF and wait at least 10 seconds.
    3. Turn ignition switch ON.
    4. Turn ignition switch OFF and wait at least 10 seconds.
    5. Start engine and keep the engine speed between 3, 500 and 4, 000 RPM for at least 1 minute under no load.
    6. Let engine idle for 2 minutes.
    7. Check 1st trip DTC.

    Is 1st trip DTC detected?

    YES

    Go to Diagnosis Procedure .

    NO

    With CONSULT: GO TO 3 .

    NO

    Without CONSULT: GO TO 5 .

  3. PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B 
    NOTE: For better results, perform "DTC WORK SUPPORT" at a temperature of 0 to 30 deg.C (32 to 86 deg.F).
    1. Select "DATA MONITOR" mode with CONSULT.
    2. Start engine and warm it up to the normal operating temperature.
    3. Turn ignition switch OFF and wait at least 10 seconds.
    4. Turn ignition switch ON.
    5. Turn ignition switch OFF and wait at least 10 seconds.
    6. Start engine and keep the engine speed between 3, 500 and 4, 000 RPM for at least 1 minute under no load.
    7. Let engine idle for 1 minute.
    8. Make sure that "COOLAN TEMP/S" indicates more than 70 deg.C (158 deg.F).

      If not, warm up engine and go to next step when "COOLAN TEMP/S" indication reaches 70 deg.C (158 deg.F).

    9. Open engine hood.
    10. Select "HO2S2 (B1) P1146" (for DTC P2270) of "HO2S2" in "DTC WORK SUPPORT" mode with CONSULT.
    11. Start engine and follow the instruction of CONSULT display.
      NOTE: It will take at most 10 minutes until "COMPLETED" is displayed.
    12. Touch "SELF-DIAG RESULTS".

    Which is displayed on CONSULT screen?

    OK

    INSPECTION END

    NG

    Go to Diagnosis Procedure .

    CON NOT BE DIAGNOSED

    GO TO 4.

  4. PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B AGAIN 
    1. Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
    2. Perform DTC confirmation procedure again.

    GO TO 3.

  5. PERFORM COMPONENT FUNCTION CHECK FOR MALFUNCTION B 

    Perform component function check. Refer to Component Function Check .

    NOTE: Use component function check to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st trip DTC might not be confirmed.

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    Go to Diagnosis Procedure .

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.