I'm having problems with my new 3 speed wiper motor on my 70 barracuda. It goes on full speed when I turn it on, and uses a very long time to stop when I shut it of. It does not react on the other speed levels. I've tried two diffrent swiches, and it burned one of them, so I have disconnectet all the contacts on the swich now. The motor is new from Year One, had a 2 speed berfore, it worked, but the parking was not working on that one. Any ideas?