Two problems related to defogger controls have been reported for the 1999 Ford Expedition. The most recently reported issues are listed below.
My Ford Expedition stopped being able to control the temperature. I am now going into winter, and I cannot guarantee that I will be able to defrost the windows which could cause a very significant safety issue. The "blend door" is plastic in my year, and Ford changed it to nylon during the production run. I am left with a defective blend door, and vehicle and Ford has informed me that the fix ($1,700) is my responsibility not theirs. My research on the web shows that this issue is a common issue with Fords, and Expeditions and I believe that Ford has not resolved this issue because of the cost, not caring about the safety issues.
Electrical motor controlling the air blend doors located inside the air plenum has failed, and the plastic door(s) itself is cracked and non-functioning. I have been unable to direct warm air to the front window to debug causing dangerously decreased vision. 1999 Ford eddie bauer Expedition.