I'm trying to install an LED integrated light but neither the new or old light works when hooked up to the stock harness. I had to splice since the stock plug didn't fit into the aftermarket light's harness, but the original light doesn't work now either. When I hook the lights up directly to the battery they work, so its not the lights. What is the reason? could it be that the ground got lost from the battery to the rear harness, or the wires just got mangled on the way? If anyone can help please let me know, I've been puttin this thing together for too long now and I just want to get out there and ride! Thanks

 

Did anybody else have to splice into the wires or did the harnesses match together? Could it be the fuse(though I doubt it), or do all the wires from the harnesses need to be used simultaneously for it to work?(only used one harness for one stock bulb to fit to the LED taillight with only one harness(3 wires) coming out of it)

 

you did turn the ignition on right when you hit the brake right?