I have a Ford Taurus 1996 wagon. My windows (all) will fog up fast making for a very dangerous situation! My defroster both front and rear are not working. I have had no problems with the ac and heater with either temperature control, settings, or with the fan speeds. When I turn the defroster on, I have to use a towel to clear my window to see to drive because it does nothing to defrost the windows. Cracking the windows in the car does not help either. I have noticed a difference with the defroster when the car is parked vs. When driving. When car is parked nothing happens and when I drive it is like the defroster is trying to work but has no significant difference. Please help!