My Lexus is blowing out warm air even my heat is off on a freezing old day. When I turned the air conditioner on, the air was still warm. My battery went out the other day, Firestone replaced it with a new one and said everything is good and fix. When I get home, my air vent is still blowing warm air. These people at Firestore was just trying to get rid of me and make more money off other people. I am sick of these technicians. Can someone recommend a good honest technician for me please? BTW, the hot air started after I changed my own air filter. So I don't know if that is the cause of the problem.