tralier coupler on 2002 GMC Sierra 1500

getting no power to my factory trailer coupler to make my boat trailer lights there a fuse somewhere?

Asked by for the 2002 GMC Sierra 1500
Which lights are not working - all of them? There is not one fuse that would take out ALL of the trailer lights. If everything is dead there may be a problem where the trailer harness plugs into the junction block at the rear of the truck.
it was a fuse in the truck...thanks for the answer though...fixed....