A/C port?

[koda2000]

While poking around on my new-to-me '01 ST today, I saw something on the back of the A/C compressor that I've never noticed before. It looks like there's something missing. There's a black metal hard-line coming from the back of the compressor that makes a sharp bend and heads toward the radiator. I haven't followed it, but I assume it goes to the condenser. Just before the line bends there's this port-like thing pointing up that has a red plastic thing inside it. It looks like something should attach to it, but I don't see anything hanging. I don't know if the A/C works as the truck doesn't run yet. Any ideas? I can take a pic of it if that helps.

Note the thing in the center of the second picture from the left... What is that?

http://s1303.photobucket.com/user/kodabear2000/library/?view=recent&page=1

 

[429CJ-3X2]

Should be where the pressure switch is, so there should be a wiring harness to plug in there. Looks like the switch itself might be gone too. Either way, your a/c doesn't work at present.

 

[koda2000]

Should be where the pressure switch is, so there should be a wiring harness to plug in there. Looks like the switch itself might be gone too. Either way, your a/c doesn't work at present.

That's not what I was hoping to hear... I'll have to try to find the wiring/plug for it.