One problem related to defogger heater has been reported for the 1999 Ford Windstar. The most recently reported issues are listed below.
While turning on the defogger or heat it failed to come on. This caused poor visibility while driving. Consumer took vehicle to the dealer for inspection, mechanic advised consumer that the problem could be fixed, but the consumer would have to pay for the parts and labor. It was later determined that he blend air door was broken which would not allow heat to blow trough any of the vents.