Just wondering if anyone has installed on of these on a Sportster. I'm in search of some help. I'm not sure what wires to splice into back there since each brake light has its own wiring.

 

cockerhamsg;

I am not sure what the radiantz does, but I just install a Back off XP module(flashes 4 times when brake is applied) on my 08 Nightster. On mine I have separate wiring too, thru a tail light converter module. The Backoff XP splices between brake light switch and tail lights. The brake light switch has 2 wires, an orange/white and red/yellow.I spliced in on the red/yellow, while the orange/white is battery power. Hope this what you want......Jerry

 

I've got the manual and have done the figuring on the harnesses back there, but well, I went to splicing and I'm not getting what I need. The Radiantz has 3 wires, to be spliced into the ground, the "hot" wire (goes live when the brake is applied), and to the positive of the lights, which to me is the toss up wire. So right now I am spliced into the ground and thats it. I'm thinking I should splice the hot wire into the red/yellow, and the positive wire, which seems like the ignition source, into the orange/white. I hate wiring! Haha

 

So I just tried that, and all it does it make the brake lights come on without hitting the brake lever. So I switched the wires, and it makes the system cycle through its function upon contacting the wires, but again, this is without hitting the brake lever. So I'm lost even more now.

 

cockerhamsg;

When I was talking to Patrick from Signal Dynamics,in reference to which wire(red/yelow or orange/white) to splice into, he said

"If you have a test light handy, press your brakes while having the test
light hooked up to the yellow/orange wire. If that wire is constantly
lighting your test light without you touching your brake, that is your
running light wire. If it only lights up when the brakes are applied, then
that wire is your brake light wire."

this sounds like your problem. Also when I first hooked mine up, I had my ground wire spliced into the black brake ground wire, my backoff xp didn't flash, the brake light came on as normal. So I unspliced and grounded the wire to chassis with a screw and everything worked........hope this helps....Jerry

 

Yeah i dont want to sound smart , the test light is your best bet

 

Right on, thats a great idea. And I have a test light, so looks like I'm headed to the garage.

 

The orange/white wire is indeed the power wire, while the red/yellow is the brake hot wire. So upon reinstalling the correct way, again, it still doesn't work how it should. So I am left to believe that it is defective. if I switch the two power wires, it will work like I said before, upon contact it will cycle and stay lit but thats all. All I can figure is that I need to give 'em a call and get a new one.

 

To update this, I got a new module in, installed it and it did the exact same thing. I can't figure this thing out. Either the instructions are wrong, which I doubt, the bike isn't capable of running a device such as this (that has 3 wires) because of factory wiring, or there is some other combination of wires that need to be tapped into. Any more ideas before I send this thing back and call it quits?