The Climate control switch you mentioned in your first post is probably the auto head unit, sometimes called the Climate Control Unit. I would say that, short of a loose ground or broken wire, it is probably this unit. Try checking the ground wire and check the 10A HVAC fuse and replace it, be sure and clean the contacts in the fuse panel before installing the new fuse. If all this fails then check ebay for a new control unit.
Below is a link to a control unit on ebay that will be over in approx. 2 days. It is at $9.99 right now. I have seen them go for less than $20.00 for a used one all the way up to $175.00 for a (supposed) new one.
Do a search on Ebay motors and there is almost always one for sale.
http://cgi.ebay.com/ebaymotors/1998-...QQcmdZViewItem