I have done a search for this and have come up empty. I've been having this weird issue with my 03 Lancer ES. Whenever I turn the vent on to just bring in some cold outside air, the AC kicks on. I do not actually hit the AC button yet it still kicks on. Once I press the AC button, it lights up green, and continues to blow out cold air. I can press the AC button again to turn it off and it still keeps the AC on. The only way I can actually get it to turn off is to the fan speed to off. I have not tried anything as I am completely lost on this issue. Any help would be greatly appreciated.