Ok so here's the story. I bought my RG about 5 years ago. It had the box style tail light with the running light and brake light function. The turn signals were on the brake light bar and were turn signals only.

About 2 years ago I decided to repaint my bike so I wanted to upgrade the rear fender. So I bought a complete rear fender from a 2012 Street glide. It has the tribar light, and the light bar for turn signals, running light and brake light.

I bought the correct harness to go from the tribar to my stock lighting harness that used to run to the box style tail light. I put the correct plug on the new harness (male) and repinned the plug to match existing plug (female).

The tribar that came with the fender worked like this:
Running light worked fine - large filament lights up
Brake lights worked fine - small filament lights up both sides
Turn signals do not function correctly - when I push either turn signal button all the turn signals flash at once like hazard lights, front and rear together small filament

So I've bought two more and these to don't work either.
They both work like this:
Running light works fine - large filament
Brake lights don't work at all
Turn signals work correctly - small filament

So is it possible I've just bought 3 junk tribars and my issue isn't wiring related?

To me that seems like the issue but what do I know.

BTW all three tribars are the same part numbers.

This has been driving me crazy last couple years. I don't ride the bike much so I wasn't worried about it too much.

Any help would be greatly appreciated.