Hey everyone. I just picked up a 2008 nightster with low miles. Loving the bike so far but have a question that maybe someone can help me with. I bought a no school choppers side mount plate kit with a taillight. I want to be able to wire up the taillight to work as a running light/brake light and also keep the factory setup working as well. I'm having a hard time figuring out where to splice in the wires for the new light so that it works as a run/brake light and doesn't blink when I turn the blinkers on. I'm guessing if I tap into the wires going to the left brake/signal light it will flash with my left blinker on. Anyone have a good idea of where to splice in? Any help would be greatly appreciated

 

Test with the orange/white or the red/yellow with the black as a ground and see if it works for what you are trying to do.

 

Thanks I will try that. I figure in going to have to tap in before the module and see if that works.

 

Nightster was the OG sportster with no center brake light. They are set up,with lights that are run/brake/turn. If you are trying to splice into the stock wires, you'll run into problems. I'm fairly sure that the signals are all generated by the TSSM into the rear lighting harness. I've never tried to 'downgrade' a Nightster to 'traditional' wiring. However, all of the wires for the lighting are in the connector leading to the TSM (or TSSM) under your seat ... Tap into the wires there ...
MAYBE (check for yourself) yellow/red for brake and blue for run ...
MAKE SURE that the brake light is active for both brake switches (front and rear)
Good luck!