Typically a blend door actuator will fail either the all the way to hot or all the way to cold position. Of course it would have been easier on you if it was stuck on the cold position given it is middle of summer.
The blend door actuator can be accessed by removing the glove box.
It is not terribly difficult, just time consuming. When you remove the glove box you will see the actuator on the top of the HVAC box.
Here is a helpful video of how to replace the actuator, this particular video is on a explorer, but the basic procedure is the same as your ranger:
Please let me know of any questions.
Images (Click to enlarge)
Friday, August 6th, 2021 AT 2:28 PM