I have an 05 Grand Prix and the air won't work for some reason. Some days the fan will blow and some days the fan won't. I have had the fan switch go bad in other cars before so I bought one from a wrecking yard and switched it out yesterday. The fan worked all of yesterday and I thought that I had fixed the problem but this morning when I went back out to the car it won't work again. I didn't know if anyone has had this problem and if it might be a resister because I have heard about those going bad but I don't really even know what that is... Any help would be much appreciated...