Look at the bulb used in your fixtures. If automotive bulbs, then they are 12vdc. If screw in household bulb, then 120vac.
2012 F350 6.7 L dually, 2013 3800RE with 6 pt leveling, Sumitomo 17.5" load range h tires, Samsung 18 cu ft residential fridge, 8k Morryde I.S. with disc brakes. Full timing since 2012.