Wiring problems of the 2003 Nissan Xterra

I own a 2003 Nissan Xterra with 7400 miles on it. On Wednesday, February 25, 2004, I attempted to roll down my windows and all four windows were powerless. I called conicelli Nissan service in conshohocken, PA immediatley and brought it in for service the next day (February 26, 2004). During the first service check, the technician could not duplicate the concern and did not fix anything. On February 27, 2004, the exact same thing happened to my windows. This time my front, right, driver-side window was down and I was not able to get it up. I immediately called conicelli, explained the situation, and drove directly to the dealership. This time the assistant service manager and technician were able to see for themselves the problem. They had to connect a charge to the wire to roll the window up. I was told to come back on Monday, March 1, 2004. On March 1, 2004, they replaced the master panel switch and tightend up a wire that was apprarently loose. The service was done from the direction from a Nissan techincal call. On March 3, 2004, while I thought my car was fixed, I once again attempted to roll down my windows and they were powerless. I called conicelli Nissan and drove directly to the dealership where my car remains today (March 4, 2004). I have not heard back from the dealership yet. I am completely baffled that my car has been looked at three times in six business days and my windows are still not working properly. Maybe the fourth time will work.