Limbic

Hi guys,
With my camper plugged in yesterday I turned my headlights on (aftermarket HID), heard a buzzing sound under the hood, and now have a few electrical items not working.
Airbag light (red) is on on the dash, turn signals don't work (although hazards do), seat heaters won't work, and the climate control system is completely off line.
The headlights still work fine.
This sure sounds like a fuse/relay, but I have not been able to find anything that's blown.
Any thoughts on what could be the cause? I've heard of the body ECU as a possible, but don't know much about it.
Any help is much appreciated!