My left headlight went out the other day. I replaced the bulb (Xenon - which cost me $99) and hooked everything back up, but it didn't work, so I tried again, and still no go. Frustrated, I slept on it. The next morning I took it apart and put it back together again and, Eureka, it worked fine. But my wife took it to the store later that night and she said the light started blinking after about ten minutes and then it went out. So I took it apart and put it back together, and it worked fine - for about 20 seconds, and it hasn't worked since (three days).

I switched the right and left transformers, and that's not the problem.

Does anyone have any ideas?