I have my 09' Nightster and I am trying o add a set up for the brake lights called rear alert... www.rearalert.com, I see that each tail light is in its own independent wiring harness, but where does it split from. Is there a single wire coming from the brake switch thru the harness, then its splits up... any help would be appreciated. thanks...

 

If you're trying to get the flashing brake light feature, HD makes what's called a run/brake/turn module that will flash your brake lights, it just plugs in under the seat (~$.60.00). It was designed for standard Sporties with a fender (center) mounted tail/brake light, but should work on the Nighty.

 

Yes, there is one wire that comes through the harness and goes to the brake light. On an '05 it's the red/yellow one. I can't think of any reason why they would change the color on the '09s.
Say- you're not working on your bike without a manual, are you?

 

2006 is red/yellow as well.The manual kind of hides the diagrams in folded pages near the back of the manual.

 

What he said... spring for a manual. I've done a bunch of electrical stuff to my bike. EZ with a manual... PITA and potentially destructive without it. Just MHO of course. :-)

 

Manuel..... I know that fool..... LOL, I am gonna pick one up... I really need one to do it right. Thanks guys....