Hey everyone. I have a 06 Trailblazer ls ext with around 79000 miles on it, and I was driving around the other day and the heat and air conditioning switch stopped working (0-5). I tried playing around with what numbers it will work on and it has only worked on 0, 1, and 2. Before this problem the number 4 was the only one that would not work, and it was like that when I bought the car. I just want to know what I need to do to get it fixed, because winter is coming and I would like to be taken care of with some warm air in my car. Please help! Much appreciated.