my 3's in for service

[3Hummer]

well time for an oil change/ tire rotation...but had some things i wanted to get taken care of, most importantly my Air Conditioner. It only blows cold air when the temp meter is as cold as it could possible go, if not it blows hot air. So while iw as getting those things done, i decided ill just do everything while im at it...had a squeeking sound from my back right door everytime it was opened/closed, replacing the wiper blades, and taking care of a little ding that some got on my back left fender flare, and also doing a front end alighnment, so they have my car till either tomorrow or Saturday so in the meanwhile im driving my dads car which is pretty fun....anyway have any of you guys had the issue with the A/C???