2004 2.7T

I was driving down I-495 at night, it was about 80 deg outside and I had my "auto" air set for 75 degrees (both sides). As I continued to drive all of a sudden i felt an out pouring of hot air, I looked down at my temp control and it was on "HI". I tried to turn the temp down but the temp wouldn't change, so i tried turning the fan (and ultimately the air flow) off and that control wouldn't respond. So I turned the air to the window vents, which took it off "AUTO" and then i was able to turn off the system. I waited 20 seconds, turned it back on, turned the temp down from HI to 83 degrees when it wouldn't let me lower the temp anymore. I did the same thing again, turned on the fan for the window, turned off the fan waited 5 mins and turned the system back on. Haven't had a prob since (this was Friday of last week).

Anyone else experience a similar problem? i am getting ready to go on an 8-hour trip and I would hate for it to be 90 outside and my temp get stuck on HIGH and not be able to turn it off (anyone know which fuse controls the temperature?). Any suggestions or advice is greatly appreciated.