Ford five hundred a/c problems

Yes, I can always get hot air when I set it to hot and it does always get cooler when I go colder. I do have auto climate control, is the diagnostic test something I can do myself or just the dealer? I dont know what my pressures are at this time, (no gauges). I did find a TSB for 2005-2006 five hundreds #19107, mine is an 2007, for noise in the passenger compartment-air inlet door inoperative (recirculation). Could this possibly explain my problem? Are TSB’s handled at Ford’s expense? or are they just guidelines for the tech to work on. If I would still have to pay, I would try to put it on myself. I called the dealership and the door actuator is only $33.00, I would try to put it on myself if I knew were it is, anyone know?