2003 ultra classic I have no running rear lights or brake light. Blinkers work as should. Checked fuses, I can tell brake relay is engaging because I can hear it. This problem began with my losing the plug off tour pack harness.. I have since isolated wiring but have not replaced tour pack plug.

Put on your 4 way flashers, walk around vehicle to see all working. Stop/Turn goes through Signal Head(Combination Switch). If they work, wiring is good from switch to bulbs. Remove plug at brake switch, jump with a wire, see if brakes go on?
Good Luck