air condition not working

Can someone give me some hints on what could be possibly wrong. The heater works fine but if I put the a/c it blow air out but its just warm air, not sure what elese there is to say right now, ask me a question and I'll answer it. Thanks for any help. Brandon

A model year for your XJ would be helpful, as circumstance as to why the AC doesn't work varies....

His profile says a 1991 XJ.
My first guess would be low refrigerant level.
Does your Jeep use R-12 or R134a refrigerant?
R-12 has threaded high and low pressure connectors, and R134a has quick-disconnect connectors.

Some A/C systems have a dryer with a eye on it. If you see a lot of bubbles in the stream, then you’re running low.

You could just have a leak. If you have a R134 system, you can buy a pressure gauge at the local auto store. Be careful and good luck!