towing question

If I remember correctly there is a pin in the plug if you are running the 7 pin for the reverse lights to be hooked to, I'm not sure it is actually hooked up from the factory, I know mine isn't.

I would chaulk your wheels, turn the key on (don't start the truck) and put the truck in reverse, if your lights on the truck are on and you don't find a hot pin in the plug more than likely it isn't hooked up.