windsheld wiper problems

I replaced the switch after talking to the engineer that designed the switch and it did no good. I have no idea as to cost. I did not pay for it. I had been complaining to the manufacturer from the very first time I turned the wipers on. it was replaced, actually for the second time, in the spring of 2012. I really did not complain the last time when it was replaced. I just resigned myself to the fact that I was going to have to pay and told them to fix it and I would pay regardless of cost because I paid 100's of thousands of dollars and any fix they could do would be small by comparison. They did it as "good will", but there was many many documented failures over 4 years for which they had paid for warranty work that was totally unsuccessful .