I live in the OK flatland. My wife and I drove our 2009 Honda Accord (w/about 7000 miles on it) up to the Sangre de Christo mountains in New Mexico on a fly fishing and horseback riding trip. The air conditioner went out at some point. The fan was blowing fine, and cooler air (cooler than outside) was blowing, but it wasn't cold. Then on the way home, after about six or seven hours on the road, (just outside of Oklahoma City) it got cold again. Since it got cold again, it wasn't a freon problem. It's obviously not a bad fuse. Does high altitude screw with a car's air conditioner?