00BUCKshot!

Wanted to get some input from you guys. My 2007 Silverado seems to be having some issues regulating temperature. In order to get warm/hot air to blow, the only temperature setting I can use is 90 degrees. If I drop it down to 89 or below, it will only blow cold air. My initial thought is that the climate control module is failing but before I go spending, wanted to see if anyone else has had a similar issue or knows of a way I can test it before purchasing a new one. Any assistance would be greatly appreciated.