Unless they have been changed, your lights are 12V. Which doesn't require the inverter. They will run off the battery.
Your rig probably has a converter, not an inverter. That is what they normally come with until you get into the higher end units.
2008 Cruiser CF26RK
2013 Ford Eco-Boost
Heavy duty payload - Max tow
read my answer on the other post you put up today. might help.
It was a rainy few days at Algonquin Prov park...tarps kept us dry.
Wayne --Belle River (Windsor), Ontario
2013 Sunset Trail Reserve 25RB..
2015 White Chev Silverado 2500HD 4x4 (6.0 l gasser)
2003 Mountain Star 890SBRX Truck Camper