Open up the tail light and move all the wires around. Then start the bike. If it works, It is a short back there just do further inspection and fix that bare wire that is shorting out to tail light case.
Yes i am serious.
Had I known you had that Module,
I would have directed you to disconnect it.
But everyone should know that when this happens, go to the rear. ESPECIALLY if you have added something, The extra wires cramp up in there and make things rub bare and short out. \
Yes I am serious.