I bought this same cheap light for my new to me Gen 1 and found the the 3-prong plug came wired wrong. After doing some testing with my test light, I found that IN MY LIGHT, the red and black wires were in the wrong spots on the harness coming from the light to match up with the harness feed from the bike. I simply pulled those two wires (there is a small clip that holds them in), plugged them in the correct locations on the harness and everything worked. The turn signals get their ground from the main ground in the 3-prong plug, so you will only need to use the hot lead from each factory turn signal lead to get the signals to function properly. I pulled the factory plug/harness off of the signal wire ends and used it since the signal wires came with the correct ends to slide in to it and you just need to make sure that it is in the correct slot then there isn't any splicing. The two black or one black and one black/white wire that come out of the bottom are to run the plate light. This needs to have power when the bike is on, so I hooked one wire to the black ground from the light's 3-prong plug and the other to the white wire which is listed as the running light wire from the light's 3-prong plug. This was not as simple as the plug and play that it was for my wife's FZ6R, but with a little bit of time AND some knowledge of wiring, etc you can get it to work. Hope that this helped some. Erik
Just hit left or right turn signal and touch wires and solve the mystery 
