2008 Buick Lucerne Owner's Manual - Page 160

Operation ( (Off): Turn the left knob to this position to turn the climate control system off. Outside air still enters the vehicle and is directed to the floor. The airflow direction and temperature can be adjusted, as indicated below. 9 (Fan): Turn the left knob clockwise or counterclockwise to increase or decrease the fan speed. The fan speed is temporarily reduced between the transition to a new mode. The fan will resume when the new mode is complete. ) (Bi-Level): This mode splits the air between the instrument panel outlets and the floor outlets. Slightly cooler air is directed to the instrument panel outlets and warmer air is directed to the floor outlets. This mode automatically uses outside air and directs most to the floor outlets. Some air is directed toward the side window outlets and to the windshield. If recirculation is selected while in this mode, it stays on for three minutes to reduce windshield fogging. 6 (Floor): h (Recirculation): If the airflow seems low when the fan speed is at the highest setting, the passenger compartment air filter may need to be replaced. For more information, see Passenger Compartment Air Filter on page 3-30 and Scheduled Maintenance on page 6-4. Temperature Control: Turn the center knob clockwise or counterclockwise to warm or cool the air coming through the outlets. Mode Control: Turn the right knob clockwise or counterclockwise to change the airflow direction. Press this button to recirculate cabin air through the vehicle. An indicator light below the button comes on to show that this mode is activated. This mode can be used to prevent outside air and odors from entering the vehicle or to help cool the air inside the vehicle more quickly. This mode cannot be selected while in the defog or defrost modes. If you try to select the recirculation mode, the indicator light flashes three times and turns off. Operation in this mode during periods of high humidity and cool outside temperatures may result in increased window fogging. If window fogging is experienced, select the defrost mode. H (Vent): This mode directs outside air to the instrument panel outlets. 3-22