I only had to undo the passenger side, I removed the glovebox and there are a set of regulator motors, two with green arms and one with an orange arm. I turned the air on and when you press various combinations, the motors all move. My temperature regulator (orange arm) didn't move when I changed the temperature so it was stuck to hot. I pushed it with my finger and it worked.
If you get hot air from all vents could it be a fuse?