hi I am having some issues with selecting either floor or vents seems to be defaulted to defrost, not sure if it is a blender door issue or maybe electrical, i checked fuse 24 in the fuse panel it was ok, I don't hear any thing trying to happen when you change the selector and if you select a/c i don't here the fan speed up like it usedto. just hoping some other reader may have some ideas as to what to check next, I don't have a manual for the truck yet, soon though.

Thanks in advance Warren in the great white north!

 

Welcome to the site Warren..

The 'default' position for the venting is 'defrost'.. Since you stated that your truck is a 7.3 in yourother thread,, they have a vaccum pump on the right/passenger inner fender that supplies vacuum for the climate/vent system as well as ESOF 4x4 if equipped.. If you pull the small vacuum hose off of the pumps nose, it should run with the key ON to prove it's function.. Also the reservoir connnection if removed should 'bleed' off the stored vacuum and the pump will run. Without a working vacuum pump and the stored vacuum depleted, or if there's no power distribution to the pump, the vents will always default to the defrost position..