If you haven't had the bike since new, the first thing to do is look for a "Shade tree" wiring job, like when the turn signals are re-wired after the fender eliminator kit is installed.
Most folks have no idea how to properly re-route, connect and splice wires, even less on wires that are exposed to the elements.
You may find a short in such a place. Otherwise, it's detective work.
One trick is to work in very dim light. If it is a gross short, with a hot wire touching something, you can root around and you may see an arc when you move the offending wire.
Good luck! Keep us "current" on your progress!