LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Infiniti >> 2008 >> G35 Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P0137 Through P0430 >> DTC P0138, P0158: Ho2S2 >> DTC Logic >> DTC Confirmation Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC Confirmation Procedure

  1. PRECONDITIONING

    If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.

    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. Start engine and keep the engine speed between 3, 500 and 4, 000 rpm for at least 1 minute under no load.
    4. Check 1st trip DTC.

    Is 1st trip DTC detected? 

    YES: Go to "DIAGNOSIS PROCEDURE ".

    NO-1: With CONSULT-III: GO TO 3.

    NO-2: Without CONSULT-III: 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 °C (32 to 86 °F).
    1. Select "DATA MONITOR" mode with CONSULT-III.
    2. Start engine and warm it up to the normal operating temperature.
    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. Make sure that "COOLAN TEMP/S" indicates more than 70°C (158°F).

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

    7. Open engine hood.
    8. Select "HO2S2 (B1) P1146" (for DTC P0138) or "HO2S2 (B2) P1166" (for DTC P0158) of "HO2S2" in "DTC WORK SUPPORT" mode with CONSULT-III.
    9. Start engine and following the instruction of CONSULT-III.
      NOTE: It will take at most 10 minutes until "COMPLETED" is displayed.
    10. Touch "SELF-DIAG RESULTS".

    Which is displayed on CONSULT-III 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 ".

scientia non olet · About LEMON Manuals