7 pin plug

[submirj]

I have a new gmc truck , how can I tell if the battery charge pin is hot and will charge my new airstream battery.? Will it show on the monitor gauge? Since it is a new truck , i amnot sure the batery pin is hot.

[robert claus]

Start the truck and check the pin with a test light. Turn the truck off and see if the pin is still hot (some vehicles are constantly hot and feeding off of the tow vehicle battery, others turn off the circuit with the ignition).

[lsbrodsky]

Agree, you need to put a test light or voltmeter on that pin and ground. Recent GM trucks, maybe always, have that wire not connected through the ignition so that once connected it is always hot. Beware, that means that you must unplug when not running the truck or you risk running down your truck battery.
My truck came with the towing package and the trailer charging battery connection was connected under the hood. Most descriptions/instructions lead you to believe that this wire is not connected from the factory and tell you how to connect the wire. Plenty of stuff on the internet about how to do it.
Larry

[sb55]

I had to hook up 2 wires to the studs next to the fuse block, and also buy 1 fuse. For some reason , GM leaves out that 40 amp fuse. I found the several videos on e-trailers.com, but every video does not mention that fuse.

[ROBERT CROSS]

The Power Distribution Center, under the hood, left side under the plastic cover.

If yours looks like this.

The charge wire connects to 'stud #2', top right.

Bob