I have a Northstar 8.5 Arrow mounted on my 2015 Chevy 2500, 4X4, long bed, single rear axle. A friend told me that when the truck motor is running that it is supplying power to the camper's on boar...
Some GM trucks require termination of a wire either on pin 1 or 2 depending on the year, then the installation of the 30 amp fuse. I would suggest installing a relay to isolate this circuit to prevent running down the truck battery. A good example with instructions is this one from Tekonsha. Battery switch