My 08 Ranger has no temp control. I can freeze myself out or boil myself out of the cab but there seems to be no feathering of the temps? So it has full capacity to do eigthr I just cant set the temp to a temperature and control it. Looking on line I think I have the old white damper motor, Where is the most likely issue is it in the **** with the red/blue temp range or most likely the damper motor. seems odd to me that it woudl be the damper motor if it will do both heat and cool to full but I dont know how that plays a role in the process.

 

It's called the Blend Door motor, its an electric motor, and it is the only thing the Temp Control **** adjusts, so that would be your problem

Its possible the ****'s resistor is the problem but its a long shot since the Blend Door motor is a common issue on all Fords

Google: Ford Ranger blend door

Loads of videos and how-to's

Yes, it could fail as an all or nothing, the blend door covers the heater core, so when its wide open ALL air from the fan goes thru the heater core, so HOT air
When blend door is fully closed then NO air from fan goes thru the heater core, so COLD air

Once you have the Blend Door motor out you can plug it back in and turn on the key, then adjust the Temp **** to see if motor moves just a little(so would move the blend door just a little) if so then it could be the blend door it self is broken, the door could have a broken tab so air flow holds it open fully until motor turns all the way to force it closed

You won't know which it is until you disassemble it to get the motor out