I recently purchased a 2000 STS. When I test drove the car it was the middle of the day and blue skies and sunny. I thought nothing of testing the wipers. When I was driving back to town I tried my wipers and they didn't work. I left to go to work later on that day and they worked just fine. The rainsense was working and everything. When I left work that night, they worked, when I left the restaurant later on that night, it didn't work and it was pouring down rain. The next morning, the windshiled had frosted over and when I got up to warm the car up, they worked. I tried them later on that day and nothing and they haven't worked since. I have checked the fuses, relays (they are all getting power), bought a new switch, that wasn't the problem. So I am not sure if it's the motor or if it's the wiring harness. As far as the headlights go, they worked up until a few days ago. My fog lights worked and always have and when I first noticed the issue, the only thing that worked was my fog light and passenger high beam. I stopped at the auto parts store and bought new low's and high's, put them in and still the same thing, just the passenger side high beam worked. I left the grocery yesterday and it was starting to get dark and I turned on my low beams, they still didnt work but both of my high beams worked. I am not sure if there is a short or what is going on but I am stumped.