GM Service Manual Online
For 1990-2009 cars only

The HVAC module contains a series of air doors. These doors are hinged parts that direct the airflow through various sections of the HVAC module. This action provides the proper airflow for the selected operating mode. Each air door is controlled by an actuator.

Ducts and Outlets

A system of ducts and outlets directs air to the passenger compartment.

If the air output is poor, inspect the following areas for obstruction:

    • The defroster
    • The heater
    • The air conditioning
    • The vent ducts