On a 1999 Ford Windstar is there fuse in the temperature control slide?

No, there's no fuse *in* the temperature control slide itself on a 1999 Ford Windstar. The fuses for the climate control system are located in the fuse box (usually under the hood and/or inside the vehicle, depending on the specific model). A malfunctioning temperature control slide is more likely due to a problem with the slider itself (worn out, broken connection), a faulty control module, or a wiring issue, rather than a blown fuse.