Hello,

I have a 2005 F150 Lariat. I ususally run the HVAC on auto and noticed this winter intermittently hot air blowing out the dash vents instead of the floor. When I would try to change it to the floor or any of the blend modes nothing would happen. If I would choose the defrost the air would change from dash vents to defrost and then I would be able to choose the floor or blend modes. Again 9 times out of 10 when I start the truck in the auto mode the heat will blow out of the floor and all functions of the HVAC system work fine...just that 10th time or so that it get hung up on the dash vents and will not let you change to anything but the defrost. Temperature control and fan speed controls work just fine. Ford dealer found the control module to be faulty and change it under an extended warranty but issue still there. Any ideas as to what could be going on would be appreciated. Thanks