You are correct, it sounds like the mode control actuator is not working correctly. Here is the location so you can swap it out which should fix the problem. Also, when the actuator is removed move the blend door pivot by hand to make sure there is not an obstruction inside the vents. Check out the images (below). Let us know what happens and please upload pictures or videos of the problem so we can see what's going on.
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Thursday, April 13th, 2023 AT 12:15 PM