Ozzy88

Hi all, I'm new to this site, and new to Lexus. I just bought a 2001 IS 300, as is of course. Air conditioner worked great, and the heater. I turned on the heat to defrost the window, and tried to cut on A/C later that day. Only blows hot, like the gate is stuck. Compressor works and runs great, so what's a way to check the gate? Is there a fuse to the gate? Is it an elec motor that turns it, vacuum line? I have no idea. I would like to fix it myself, as I am short on time, and can't really go without the car, I travel a lot. Please help!