I am having an issue with my headlight switch, I think its looking like a bad switch. When I turn the headlight switch to the left to turn the headlights on(from auto), nothing happens. Maybe one out of 20 times the parking lights came on only. But for the most part nothing happens. If I have the fogs on, the fogs stay on as it should when turning the headlights on and the fogs turn off when I turn the light switch again as they should. I am 90% sure its the switch, but this part makes me think there may be something else. If that function of the switch was bad wouldn't the fogs just stay on instead of turning off with the headlights? If I turn the switch to "On", the headlights come on fine. They also come on when set to "Auto" and the sun goes down enough to trigger the auto sensor. I don't think any of this matters but will mention it anyway - 2008 Sierra with HIDs projector CCFL Halos.