Ok sorry I may be missing something because it was some time ago. I believe the remaining wire is to the running lights (LEDs). Sadly, those things are NOT on the Recon backup light. They are the little DOT lights for having a really wide vehicle. So the Recon light wont have that feature and you wont need that wire. I just sealed it up...
Here is my recollection of what I did:
- There are 3 plugs on the stock light. For the reasons noted above, I did cut off all 3 plugs. HOWEVER, if you are having some problems, I would start by just tapping the wires. If that works, you can cut and solder/crimp as desired...
- The 2 side plugs are black/white and just control the backup lights. As I recall, you will only need to use the black one there or whatever I said in my notes.
- The middle plug has 3 wires. One is ground, one is to the brake light and one is to the running lights. I dont recall the colors but I believe I used the ground and brake only. The other wire I just taped as noted above.
The way I tested all of this was to unplug the stock light and use aligator clips to attach to the wires I noted above. Once I confirmed that worked, I then taped into those wires to confirm it worked right (with no CELs or warnings). When that all worked, I then (and only then) cut wires.
I hope this helps...