AC Blowing through defrost only..

among other things. im having some issues with my A/C.

1. Im getting constant power to my ac clutch. followed the wire and its wired into my ignition switch. im sure it should go to a pressure switch somewhere..so i dont know where that is, or what original wire the ac clutch is supposed to connect to.

2. When my AC is on, it only blows out the defrost vent. i can hear the blower motor turning on, so i know thats working.

3. When the AC did blow through the dash vents, it wasnt strong at all.

94 International 9400 Dump truck
any help greatly appreciated!

 

i did pull the dash panel off. the levers move freely and i see the cables moving...but i cant see the other end where the cable goes. but it is a little stiff but it has always been that way

 

somebody definitely has been lazy. i dont think they even bothered looking for a pressure switch, which is what im hunting for, along with the the original wire thats supposed to be plugged into the ac clutch.

ill try and find a way to check the doors to see if its stuck. its the only thing i can think of...

 

does anyone have a wiring diagram that shows which is the original wire under the hood for the ac clutch? i pulled my seat off and found the preasure switches...now i need to find the original wire so when i jump the pressure switches i can see if the clutch comes on