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Home >> Infiniti >> 2012 >> M37 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS U0101 Through P0153 >> DTC P0133, P0153: A/F Sensor 1 >> DTC Logic >> 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 more than 11 V at idle. 

      Do you have CONSULT? 

      YES: GO TO 2.

      NO: GO TO  5.

  2. PERFORM DTC CONFIRMATION PROCEDURE-I 

    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. Select "A/F SEN1(B1) P1278/P1279" (for DTC P0133) or "A/F SEN1(B2) P1288/P1289" (for DTC P0153) of "A/F SEN1" in "DTC WORK SUPPORT" mode with CONSULT.
    8. Touch "START".

      Is "COMPLETED" displayed on CONSULT screen? 

      YES: GO TO 3

      NO: GO TO  4.

  3. PERFORM DTC CONFIRMATION PROCEDURE-II 

    Touch "SELF-DIAG RESULT".

    Which is displayed on CONSULT screen? 

    OK: INSPECTION END

    NG: Go to "DIAGNOSIS PROCEDURE ".

  4. PERFORM DTC CONFIRMATION PROCEDURE-II 
    1. After perform the following procedure, "TESTING" will be displayed on the CONSULT screen.
      • Increase the engine speed up to about 3, 600 rpm and maintain that speed for 10 seconds.
      • Fully release accelerator pedal and then let engine idle for about 10 seconds.

        If "TESTING" changed to "OUT OF CONDITION", go to  "COMPONENT FUNCTION CHECK ".

    2. Wait for about 20 seconds at idle under the condition that "TESTING" is displayed on the CONSULT screen.
    3. Make sure that "TESTING" changes to "COMPLETED".

      If "TESTING" is not displayed after 10 seconds, go to  "COMPONENT FUNCTION CHECK ".

    4. Touch "SELF-DIAG RESULT".

      Which is displayed on CONSULT screen? 

      OK: INSPECTION END

      NG: Go to "DIAGNOSIS PROCEDURE ".

  5. CHECK AIR-FUEL RATIO SELF-LEARNING VALUE 

    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  7.

      NO: GO TO 6.

  6. 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.

  7. 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: Go to "DIAGNOSIS PROCEDURE ".

      NO: INSPECTION END