GM Service Manual Online
For 1990-2009 cars only

Use the thumbwheel below the air outlets to change the direction of the air flow. Use the vertical thumbwheel next to the outlets to control the amount of air flow or to shut off the airflow completely.

Keep all outlets open whenever possible for best system performance.

Operation Tips

    • Clear away any ice, snow, or leaves from the air inlets at the base of the windshield that can block the flow of air into the vehicle.
    • Use of non-GM approved hood deflectors can adversely affect the performance of the system.
    • Keep the path under all seats clear of objects to help circulate the air inside the vehicle more effectively.
    • If fogging reoccurs while in vent or bi-level modes with mild temperature throughout the vehicle, turn on the air conditioner to reduce windshield fogging.