C7500 Headlamps Intermittent On/Off

[NorthernX31]

I know this forum doesn't list the 7500 series but I'm hoping someone can help. 2011 C7500 box truck, headlights come on then go off. They'll come back on after a bit. I read that there's a cct breaker in the light switch itself. I'd like to confirm or rule it out but I need some help with a wiring diagram. There's a fuse box on the passenger side dash but no cover forma guide. Has anyone seen this problem before? Any help would be appreciated. I have a clamp meter for dc as well as a decent multimeter, and am hoping to save some time by asking here first.