Hot air blowing out even when AC is set to cold

I have a 2001 Cherokee Sport. My heat is blowing out hot air no matter what setting I have it at and just today I noticed that my AC is blowing hot air even when it is set to the coldest setting on full blast. Any idea what the problem may be and what to check for? This just happened recently. The air blowing out seems to stay at a constant temperature and doesn't get warmer/cooler when the temp controls are adjusted...

Other things to note, and i'm not sure if this relates, but I just got a new serpentine belt put on and a power steering pump a few weeks back.

Any help would be greatly appreciated.

It's your blend door. Maybe the stepper motor's shot, or the motor attachment point broke off (very common).

I've got same problem - is there any easy way to see this blend door and see if it's broken, or do i have to tear the whole dash apart ?

check under the dash on the passenger side it may have changed seeing as mines an 1987 but on mine there is a slider that the ajuster cable conects to sometimes the cable slips of this adjuster all you have to do is put it back on

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