Hello all. First off, this site is an amazing resource for repairing my trucks. Tech folder is in my favorites. Thanks for all the great info. I'm hoping this post may help someone out there with the same problem.
My 01 F-250's wipers would not shut off. As soon as the key was turned on they would come on. No delay but high and low only. Had to pull the fuse to drive it. I replaced the multi function switch as well as the relay with no fix. I did some reading on this problem and it is related to the "park" switch in the wiper motor itself. I took the black plastic cover off the motor which reveals the worm gear driving the plastic gear which acts as the switch. The contacts for this switch are hard to get to as they are on the backside. I blew compressed air into every little crevice and removed most of the grease. I regreased and put it back together. Sure enough the wipers work just fine now.
I am assuming the compressed air trick may be only temporary.Has anyone ever gone further to reveal the contacts for the park motor switch without destroying the plastic housing? Thanks for any input.