On my van I had a blown fuse. I am unsure what fuse because ford has no description of their fuses or locations on the fuse box cover. I beleive that in the manual they have a listing unfortunatly I did not have the manual. I just did a continuity check on each fuse untill I found a bad one. Once I replaced the fuse the problem went away. Good luck with yours!! I hope it is as easy as a blown fuse like mine was.