I had the same problem with a warranty fix. I didn't think that they would find it, because it happens imtermittently. I must be lucky with my ford dealership in Houston. Anyway, enough on that.
Getting the blower motor out is VERY easy. It takes about 5 minutes.
I can't remember if I had to remove a trim panel from underside of the passenger-side dash. anyway, the motor has two latches to disengage, then rotate it counterclockwise about 1/4 turn. It will then slide straight down. Very simple to get at.
Good Luck,
David
