use an ohmeter to check all the wiring for starters, likely be a shorted wire between the switch and the lights, not likely the actual switch

Bill

Moved over to the Passing Lane

"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir
"When we tug a single thing on an old truck, we find it falls off" ~ me
Some TF series details & TF heater pics