You'll need to replace the temperature blend door actuator, normally you have to pull the panel out to reach it but you might be able to see it if you pull a bunch of stuff from front of panel. Not a very easy job... No there aren't very many good pics of this, this pic was taken from the ford site and was about the best one. The motor will be on the outside but like I said normally the panel has to come out, not a very easy job.
Here is a guide to help you see what you are in for when doing the job.
Check out the diagrams (Below). Please let us know what happens.
Images (Click to enlarge)
Saturday, March 31st, 2012 AT 5:31 PM