I have a 1990 Lexus, and only blows cold at the lowest setting I believe is 65, and if I turn it up to 66 it'll blow super hot like it's up to 90 or whatever the max heat is so it's like it's blowing all AC, or all heat, I replaced the AC control unit with a used one so that one could have been bad too, but idk the issue, if anyone has a answer, please let me know. Thanks!