1997 Explorer - No heat control

By saying "no control of air box damper" do you mean that it won't switch between heat, defrost, vent, etc. or that you can't control the temperature?

Here's a follow-up to my own posting. By doing some more internet research, I found that this is a very common problem in '97-ish Explorers & Aerostar's, etc. The constant heat (or cold) is caused by a broken drive mechanism of the air mix damper door. I found a few websites that discuss this problem which indicate that the repair could cost upwards of $1000. However, a simple fix was outlined on several websites that show you how to do a modification to the damper door servo drive by drilling a hole and installing a drive pin (common 3 penny finish nail cut to size) on the servo shaft. I tried this today and it works fine. Time will tell.