if a pen or pencil fell down the defrost, this could be it... and you'll have to dismantle the whole thing to reach it...
Or you can do this:
remove the center counsel once that is out of the way remove the push/pull plastic guard and you should see a floor vent, move the screws holding the floor vent, pull out the floor vent and you should see a motor on your right passenger area with a white circle, its held on by 3 screws remove the screws and replace
how to replace a blend door actuator on a 1999 ford ranger
If you have the 4.6 liter expedition then you dont have a heater control valve. The problem stems from a bad blend door motor or the blend door is broken where it mates with the blend door motor. Blend door motor is located under dash board behind the center counsel. Its white in color and has a plug with 3 wires. The problem is most likely with the plastic blend door itself. The same plenum box is used on the Expedition/Navigator/F150 and you can find information on the common problem on any of these models. There is a video on YouTube showing how to diagnose and repair the system. The actuator motor is hard to get to on the Expedition, but once you get to it, the full repair for the blend door and actuator is within the capability of most shade tree mechanics. This is an expensive repair at the dealer or any garage, so a little investigation of DIY methods may be useful. Check links through my bio page as a starting point.
It is possible the temperature blend door actuator has failed. Do you hear a thumping type noise when adjusting the temperature? If so, it is highly likely the actuator needs replacing. Very common
I believe you are looking for blend door actuator???
Take old one out put new one in
the actuator door is above the actuator motor which is above the floor vent ducts in the middle of the dashboard at the bottom easy fix on F- 150 on a Expedition you have to remove the middle console first to even get to that section of the dashboard.
The blend door actuator can go bad. Big job to replace it. Dash assembly must be removed to gain access to it.
A common problem is that the blend door actuator or the blend door itself will break. The blend door actuator is just a small motor that opens a vent to allow the warm air to flow, it is cheap and fairly easy to replace with a radio removal tool. A professional could do the repair in less than 15 minutes. See "Related Questions" below for more information on the actuator motor repairs many others have done. However, on my 1999 Ford Windstar, the blend door itself broke. This repair is more costly and more difficult, perhaps $700 to $1000 to replace. I just tied a shoestring to my blend door. When you insert the blend door actuator if there is no slot for it the door is broken and you are up sh... creak. Hope it is the former. Another option is from a company called HeaterTreater - a method to repair a broken blend door without removing the dash. I haven't tried it, but the ideas behind it seem to make sense - and they have lots of videos showing the processes. http://www.heatertreater.net/Windstar%20Listing.html
The Blend Door Actuator is stuck or has failed. Somewhat of a common issue.
If you are having heater/air conditioning issues in your Ford Windstar, the first thing to check should be the blend door. Broken blend doors are the main cause of heating issues in this vehicle. The Blend Door actuator on the Ford Windstar can be found by removing the glovebox. A broken blend door actuator is almost as common as a broken blend door itself. Typically, the fix requires disassembling the entire dash and replacing the whole plenum box, which can be a costly repair. Linked here is a video from www.heatertreater.net demonstrating how to access components of the plenum box for repair without disassembling the entire dash
Bad "blend door" actuator or stuck blend door on the driver's side.
Before replacing the thermostat or any other component of your Windstar's HVAC system, be sure to check your blend door for functionality FIRST. The most common issue with heat or A/C in the late model Ford windstar is a broken blend door. A broken blend door actuator is almost as common as a broken blend door itself. Typically, the fix requires disassembling the entire dash and replacing the whole plenum box, which can be a costly repair.