Hi I own a 2018 Ford edge sel, it has L. E. D tail lights. I have bought 3 different types of wiring harnesses that plug into factory plugs, then plug it into the tail light plug, one set even had a wire that had to be hooked to the positive on the battery, neither of the harnesses would work the lights on my trailer, the wiring on my trailer is good, as for the bulbs, what do I need, or have to do to get this problem resolved

 

What are you trying to do? Sounds like you are trying to splice a trailer wiring plug into the vehicle lights harness.
If you are trying to wire up a trailer harness plug what brand wiring kit did you buy?
Did any of the three come with instructions?

 

They were Curt brand, and yes they all came with instructions, I followed the instructions, they didn't work, all three kits were plug and play

 

Ok so youve tried three different trailer wiring harness for your vehicle and none have worked.
Are you looking for someone to walk you through installing one of them or are you looking for suggestions of what others have installed on Edges?
I have installed two Curt splice in harnesses on my vehicles. The part that was most important was getting a good ground for those.
I have installed quite a few Ford harnesses, mostly on explorers but I did one a Edge that I had to splice into the wiring harness.
Are you decent/good at electrical work? Can you splice in a trailer harness and know how to find which wire is which on the vehicle to attach the trailer harness to?
I am more then happy to give you wiring diagrams for where to splice into the lights if you need.
Do you want to share the part numbers for the three harness youve tried and we can look at them.

 

I will have to wait until I get home after work, I only have the last harness I bought, the guys at the store said they would work with my led lights, and I grounded them right to my frame, all 3 harnesses were plug and play, with module packs on them, I'm not trying to splice into my factory wires on my edge

 

Ok so this is the number for the last wire harness that I got, I was told by the guys at the auto parts store that this one should work for sure curt#58953, RV HARNES

 

Ok so Curt 58953 is for towing your vehicle behind a RV. Not for towing a trailer behind your vehicle.
Based off the information you provided about your vehicle the Curt website says you need 56272.
And yes you will have to run a wire from the battery to the included add a fuse then through the firewall then all the way back through the interior to the rear of the vehicle. Getting the wire through the firewall will be the hardest part, a metal coat hanger works well but I have also used a thick guitar string to get wires through tricky places.
DO NOT INSTALL THE FUSE UNTIL YOU ARE DONE RUNNING THE WIRE.
https://www.curtmfg.com/part/56272

 

Thanks I already tried that harness set, it didn't work either

 

Do all your vehicle lights work? Didn't asking before
Did you run the fused power wire from the battery when you installed 56272?
Did any any of the trailer lights work with 56272?
I take it you have another vehicle to test the trailer lights with since you said you know the trailer lights are good.
Its possible that the kit you got was bad and should try another but generally something like this would be a user error issue.

 

Yes all the trailer lights worked before, I used a buddies truck before to tow the trailer, I did run the wire to the battery after harness was hooked up to tail lights, like the instructions said to, once hooked up we tested them with a four flat tester, didn't work right, I thought it was a faulty harness as well, took it back to the store, got another same thing, didn't work, so I'm am stumped not sure what to do now