Code Enable Criteria

• System voltage is 9-16 volts.
• Intake Air Temperature (IAT) is less than 95°F (35°C) at start-up.
• Engine Coolant Temperature (ECT) is less than 95°F (35°C) at start-up.
• IAT and ECT are within 11°F (6°C) of each other at start-up.
• Average Mass Airflow (MAF) for sample period is less than 24 grams/second for VIN K.
• Average MAF for sample period is less than 27 grams/second for VIN 1 (Bonneville, LeSabre and Park Avenue).
• Average MAF for sample period is less than 29 grams/second for VIN 1 (Grand Prix, Impala, Monte Carlo and Regal).
• DTCs P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0125, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0410, P0440, P0442, P0443, P0446, P0449, or P1441are not set.

For Bonneville, LeSabre and Park Avenue, HO2S 2 voltage remains within 150 millivolts of bias voltage, or approximately 450 millivolts, for more time than necessary. Time ranges between 2-3 minutes for VIN K, or between 1.5-2.0 minutes for VIN 1, depending upon engine coolant temperature at start-up and on average airflow since start-up.

For Grand Prix, Impala, Monte Carlo and Regal, HO2S 2 voltage remains within 150 millivolts of bias voltage, or approximately 450 millivolts, for more time than necessary. Time ranges between 95-130 seconds, depending upon engine coolant temperature at start-up and on average airflow since start-up.