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Home >> Infiniti >> 2003 >> FX35 AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1148: Closed Loop Control Function (Bank 1) & DTC P1168: Closed Loop Control Function (Bank 2) >> DTC Confirmation Procedure
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DTC Confirmation Procedure

NOTE: If DTC confirmation procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.
NOTE: Never raise engine speed above 3600 RPM during the DTC confirmation procedure. If the engine speed limit is exceeded, retry the procedure from step  2. Before performing the following procedure, confirm battery voltage is more than 11 volts at idle.

Using CONSULT-II

  1. Start engine and warm engine to normal operating temperature.
  2. Select DATA MONITOR mode.
  3. Hold engine speed at 2000 RPM and check one of the following:
    • HO2S1 (B1/B2) voltage should go above 0.70 volt at least once.
    • HO2S1 (B1/B2) voltage should go below 0.21 volt at least once. If check result is NG, go to DIAGNOSTIC PROCEDURE . If NG not displayed, system is okay at this time.

    If check result is OK, go to next step.

  4. Let engine idle at least 5 minutes.
  5. Maintain the following condition at least 50 consecutive seconds. During this test, P0132 and/or P0152 may be displayed on CONSULT-II screen. See Figure.
  6. If DTC is detected, go to DIAGNOSTIC PROCEDURE .
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