This has happened twice now in the last week. First time, we were at my sisters house and she told me I had left my lights on. I always just leave my lights on auto, so I know that wasn't the case. Last night at 3 am my lights shinning into my bedroom window woke me up. The only way I can get them to turn off is to start the truck and then stop it. If there is a thread that has already been started on this, please post a link. Otherwise, if you have any thoughts or ideas, please help before I don't catch this and it toasts my batteries. I've done nothing new to the truck in the last month other than a service.

Anyone?

I don't have experience with this, but looking at schematics below, on pages D-242 and D-243, if both headlights are going ON, they are supplied +12V when Relay-HD LP LO/HI is energized. This relay looks to be controlled by the BCM.
Maybe the BCM has issues. Are you under warantee?

http://www.gmupfitter.com/publicat/2008_BB/08REV_LDCKFST_Elec_D3.pdf

Now, I have no low beams at all. No daytime driving lights or low beams when I try to turn them on or wait for dark. Both fuses are good, so it almost has to be a module.