Blackbird51

Hi everyone,I'm new here,sorry if there is already a topic for this issue but I have an issue with my air conditioning overall.I have a 99 2.2 coupe base model with a sunroof to start.Recently I was out driving at night and I noticed a burning smell coming from the A/C,I didn't think much o it that moment but now when I shut off my car,my a/c can come on without the engine or accessories off,in other words,it has power with no key in the ignition.The light for the A/C button remains on and can be pressed to turn it on and off freely,including the **** for which vents for air to run through.

I have to disconnect the battery all the time now because I am unsure as to how much it will drain my battery and I am unsure of the range of cost it would be to take it in to a shop,I've heard 99's were notorious for this issue.Any help is appreciated,as of right now,the only thing I have to go on is a wiring diagram.

Blackbird51

Now the rear defroster doesnt work as it should figure its a wiring issue now