I was experiencing similar problems to a lot of people on this board, intermittent wiper function at first, then just a total loss of function. Weird thing about mine was that the Hi beam indicator would light up real bright when I pulled the on/off switch, but nothing would happen.
After cleaning everything and re-greasing the gears, I traced the wire and found the grounding wire for the wipers and a few of the lights was not attached to anything...
Simple fix and now I have my wipers back! At least for now, fingers crossed.