1994 Suburban blowing stoplight fuse

My sub is blowing the stop light fuse when I put on my right turn signal. I have changed out the bulbs and changed the flasher relay because it was flashing fast on the left side. I have checked the trailer hookup and they look fine. This just started a day ago out of the blue. I can hit the brakes everything is fine. I can put on the signal with no brakes and everything is fine. Both at the same time is when I get into trouble. It also will blow if I turn on the sigal with the key off. I'm stumped. Any help anyone? Update ~ unhooked the connector to the tail lights. Hit brake, put on turn signal, smoke from steering column, fuse blew again! HELP PLEASE!!!!!

remove the trailer wiring if it is a T harness adapter, it might be shorted internally

Ok. here's a wild one for ya. Turn signal switch showed signs of heat. replaced it (thought I'd never get that connector through that little space down the column) and problem solved. Thank you for the reply.:)