This is weird and I never thought this would come back to haunt me, but I use to repair and fix TRUCK winsheild wiper modules on a CO-OP when I was in school. The tracks may have burned out. There is a metal slide that sometimes burns out.
I would check Ebay first or hit a junk yard.
How many miles on the car, do you get a lot of rain where you live for yours to be used sooo much?
Peace
