One problem related to ignition switch has been reported for the 1999 Ford Windstar. The most recently reported issues are listed below.
My vehicle was running (while parked) and quit. The lights were still on, the radio still worked, and the heater was still blowing. The ignition key was off and out. I had to unhook the battery to shut the three off. Replaced: ignition switch, pcm, control modual under the dash and nothing has changed the outcome. This is a 1999 Ford Windstar.