Hello!
first check is the ac compressor; does it engage when you turn AC on?
if so, have regrig/ checked; buy a cheapo test kit to diy or get it done.
get back here w/the engagement answer and we'll go on from there;
For now, here is Troubleshooting Guide, Air Conditioning, general by polarbearinc.com
http://www.polarbearinc.com/Trouble1.htm
yo!
May I suggest you register and ask anything you need answers to at:
http://forums.bucknakedoffroad.com/index.php
Ian (Stangmata) runs the site and there are many knowledgeable people over there incl. OX1 who has written many Bronco articles in the past!
be well,
