MY HEADLIGHTS WILL NOT COME ON WHEN THE SUN GOES DOWN....HOW DO I FIX THIS??? PLEASE AND THANK YOU! :rolleyes:

RTFM. I remember reading in the owners manual about how to change all of those automated activities, but I don't remember the specifics.

If they're broken... you can always get some decent headlights at us auto lighting here: Yukon Headlights (http://usautolighting.com/gmc/). I've bought from them before... their quality is great and their support chick sounds hot :P