FLOOR Mode
WARNING: This page is about a different car, the 2002 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.
When the driver selects the FLOOR mode, air is delivered through the floor outlets with some toward the windshield and side vents. Vacuum is applied to the mode actuator through the Blue vacuum line, and to the defrost actuator through the Red vacuum line. The mode actuator will retract, closing the vent door. The defroster actuator will retract, closing the defroster door and open the heater door through mechanical linkage.