Ok I've searched and searched but with no luck. Here's what's happening:

On my 1998 XJ when I move the climate controls TEMPERATURE **** to cold (fully counter clockwise) I still get heat coming out of the vents!

I had my uncle (who works at a parts yard) send me the climate controls from a '99 XJ. Here's what they look like:



However, notice the electrical connection on the temp control on the '99 controls, and the mechanical cable driven control on the '98. Here's from my '98:



So why doesn't the air temp from the vents cool off when I put the temp control on COLD?! Any thoughts? I bought the vehicle 3 months ago and everything worked fine then. I'd put the control on COLD and the AC compressor would engage and run fine. Now all I get is heat in every position. Thanks

 

Follow the cable to the blend door. It may have stuck closed on you.

 

Sounds like your blend-air door is not operating correctly, thats what switches your temp. I've never dealt with it in the Jeep so I'm not sure on the fix but I'm sure a search would bring up something.