I have a 2004 chevy trailblazer and for some reason when im driving my head lights will just cut off, and its at night and ive noticed during the day as well, how do i fix it??

Yeah these things suffer from that the wires tend to overheat too. I've had a few of these at the shop and the culprit is the body control module in the driver passenger side. The problem is that not many shops can reprogram the module. And if you don't reprogram the module the truck doesn't turn on. Hope this helps.

It's a simple fix, at least in my experience with this problem. It's a fuse relay that needs to be replaced. Open the hood, there's a large black fuse box on the drivers side by the windshield, squeeze the clips in to open the outer cover, the inner cover just pulls straight up and out, no need to take out the three bolts. On the outer cover there's a picture of all the fuses and description as to what each fuse controls. Look for #46 on the picture, find that fuse relay on your fuse box, it looks like a large rectangular piece with a small diagonal slant at one of the corners. There's an identical relay next to it, to test to see if the problem is the relay, pull out the one next to #46 and plug it into the #46 slot. Turn on your headlights, if they work, then you need to replace the relay. Pull that relay out and place it back in to its original slot, I think that one controls the fan. Place a new relay into #46, Reassemble the covers and you're done. It's like $35-$40 at the auto parts store. There's a problem with those relays, so expect to replace them every year or two