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Home >> Infiniti >> 2021 >> QX80 Premium Select, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTCS) (2 Of 5) >> Engine (ECM) >> DTC P014E: A/F Sensor 1 >> Confirmation Procedure
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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 more than 11 V at idle.

    Do you have CONSULT?

    YES

    GO TO 2.

    NO

    GO TO 6.

  2. PERFORM DTC CONFIRMATION PROCEDURE-1 

    SYMBOL With CONSULT

    1. Start engine and warm it up to 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 1 minute.
    7. Increase the engine speed up to about 3, 600 rpm and keep it for 10 seconds.
    8. Fully release accelerator pedal and then let engine idle for about 1 minute.
    9. Check the items status of "DATA MONITOR" as follows.
      NOTE: If "PRSNT" changed to "ABSNT", refer to Component Inspection .

      DTC

      Data monitor item

      Status

      • P014C
      • P014D
      • P015A
      • P015B

      A/F SEN1 DIAG3 (B1)

      PRSNT

      • P014E
      • P014F
      • P015C
      • P015D

      A/F SEN1 DIAG3 (B2)

    Is "PRSNT" displayed on CONSULT screen?

    YES

    GO TO 4.

    NO

    GO TO 3.

  3. PERFORM DTC CONFIRMATION PROCEDURE-2 

    SYMBOL With CONSULT

    Perform DTC confirmation procedure-1 again.

    Is "PRSNT" displayed on CONSULT screen?

    YES

    GO TO 4.

    NO

    Refer to Component Inspection .

  4. PERFORM DTC CONFIRMATION PROCEDURE-2 

    SYMBOL With CONSULT

    1. Wait for about 20 seconds at idle.
    2. Check the items status of "DATA MONITOR" as follows.
      NOTE: If "CMPLT" changed to "INCMP", refer to Component Inspection .

      DTC

      Data monitor item

      Status

      • P014C
      • P014D
      • P015A
      • P015B

      A/F SEN1 DIAG1 (B1)

      CMPLT

      A/F SEN1 DIAG2 (B1)

      • P014E
      • P014F
      • P015C
      • P015D

      A/F SEN1 DIAG1 (B2)

      A/F SEN1 DIAG2 (B2)

    Is "CMPLT" displayed on CONSULT screen?

    YES

    GO TO 5.

    NO

    Refer to Component Inspection .

  5. PERFORM SELF-DIAGNOSIS 

    SYMBOL With CONSULT

    Check the "SELF-DIAG RESULT".

    Is any DTC detected?

    YES

    Refer to DTC Diagnosis Procedure .

    NO

    INSPECTION END

  6. CHECK AIR-FUEL RATIO SELF-LEARNING VALUE 

    SYMBOL With GST

    1. Start engine and warm it up to normal operating temperature.
    2. Select Service $01 with GST.
    3. Calculate the total value of "Short term fuel trim" and "Long term fuel trim" indications.

    Is the total percentage within +/-15%?

    YES

    GO TO 8.

    NO

    GO TO 7.

  7. DETECT MALFUNCTIONING PART 

    Check the following.

    • Intake air leaks
    • Exhaust gas leaks
    • Incorrect fuel pressure
    • Lack of fuel
    • Fuel injector
    • Incorrect PCV hose connection
    • PCV valve
    • Mass air flow sensor

    Repair or replace malfunctioning part.

  8. PERFORM DTC CONFIRMATION PROCEDURE 
    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.
    4. Start engine and keep the engine speed between 3, 500 and 4, 000 rpm for at least 1 minute under no load.
    5. Let engine idle for 1 minute.
    6. Increase the engine speed up to about 3, 600 rpm and keep it for 10 seconds.
    7. Fully release accelerator pedal and then let engine idle for about 1 minute.
    8. Check 1st trip DTC.

    Is 1st trip DTC detected?

    YES

    Refer to DTC Diagnosis Procedure .

    NO

    INSPECTION END