Heater Start-Up Control
WARNING: This page is about a different car, the 2002 Isuzu Axiom. However, it is still accessible from the selected car via links, so may be relevant.
When the vehicle is parked in a cold area for an extended period of time, the heater core becomes cold. When the heater is turned on, cold air is blown into the vehicle until the heater core heats up. The heater start-up control prevents blower operation to the air outlets until the heater core is able to provide warm air. Air is delivered through the defrost outlets.