[DAB]

I’ll test the circuits today with a multimeter

Originally Posted by Y2Kvert4me

Imagine the potential liability an automaker would face supplying a vehicle optioned out for towing, with a factory-installed brake controller *but not connected to power*, with only a brief mention of that rather critical detail buried in the owner's manual.

This thread seems to confirm that suspicion:
https://www.silveradosierra.com/towi...on-t53137.html

I'm willing to bet you're already good to go. But even if not, unless you're hauling it back from TX full of water, I can't imagine the empty weight of the trailer being significant enough to need trailer braking for that trip anyways.
Like towing an empty car hauler, you'll basically need to dial the braking down to zero to not watch the trailer tires lock up and go up in smoke every time you tap the brakes.