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How to Splice and Extend a Wiring Harness

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Hey friends. It's Len here at 1A Auto. Today I want to show you something super cool. We're going to be splicing in a wiring harness from having one light pod to having two. It's going to be super easy. I can do it. You can do it too. As always if you need any parts, you can check us out at

Thanks. Okay, friends. So we have a kit. You can get an light pod, a little mounting bracket, and all your stuff right here. The only problem that I have with this wiring harness is it's set up for one pod. While that's cool and everything, but I don't want to run a whole wiring harness, you know, two of them running straight up and down the whole truck. Why do that? So I'm going to show you something very basic. We're going to splice it in another end here and it's going to be great because then we can use two pods, one for each side of the bumper under there, and it's going to be awesome.

Let's do it. All right, so let's open up this harness here. We have our battery connections. Positive, negative. We don't have to tell you. The positive has a built in fuse right here. It comes with a fuse right in it. If you need to replace it down the line, just grab it, pull it right out, replace it with another 30. We'll put that back in. Close this back up. Keeps it nice and water tight. Would I say it's waterproof? No, I wouldn't, but to continue. We've got our relay. This is super important. We'll follow this down. We'll take one of them. We followed it down. We have a connector here, which is great because on this side we have a switch.

If you wanted to, just squeeze this tab, you can separate this. Have you switched inside your vehicle obviously and then you can run your wire and you don't have to worry about trying to run this through a small hole. Okay. Find the other end. All the way down here. Ta-da. We have the end that goes into the light pod port right there. Okay. Like I said before, this whole wiring harness right here only comes for one light pod. While that's great and everything, but who wants just one light pod in the back or wherever you're putting it. Maybe you're putting it in the front, or the side, or you do you boo boo, whatever. We'll set the switch aside. Well, we did. You've got another one with the light pod connector on there just like this. Okay. We've got plenty of wiring because we're going to go from one side of the bumper all the way over to the other.

And then what we're going to do, we're going to take this wiring harness. We're going to cut into it and I'll show you how we're going to splice in some new wires so we can have dual pods mounted into the vehicle. So I just rolled it back up a little bit here just so we don't have a giant mess while we're trying to work. Okay. This is much easier to deal with. What we're going to do, we're going to come down this way. Maybe right about here. We don't have to go all the way super close to the connector. We'll go right about here. I'm going to cut it. I'm going to use some cutters just like that. Simple razor blade. Cut away from yourself. Obviously never cut towards yourself if you can avoid it. Grab these wires.

There we are. Wire strippers. All right in here. Give it a nice little twist. Like to maybe have a little bit more than that. Try one more time. I'm going to go with this one. That's exactly how I want it. I'm going to do the same to this one. Give it a little twist. Very nice. We'll set this aside and we'll continue. Here we are. We'll set this one aside. Got two ready. Grab our little extension cable we made here. And same for this one. So we're going to take our two sets of wires that have the pod connectors. Okay. We're going to have the other set aside. We don't need that right now. We're using the pod connector ones. Black to black. Just put them right up against each other. Give them a nice little twist. It doesn't have to be anything too crazy. This is just to get them up against each other. We're going to use a connector that looks like this.

It's got a single wire side and a nice big double wire side. That's going to be great because we're going to slide this right onto the double wire. Try to push it in there as far as we can. This is super important. You need to make sure that you get the metal parts of the wires down very deep inside there. It's in there as far as we can get it. Now we're just going to crimp this down. Right up here. Give this a nice little crimp. Okay, I'm going to give this a little tug. Sometimes with these, the inside just really isn't the best. I mean, I didn't make it so I can't really testify to quality. We'll set that aside. Let's try something a little different. We'll go with one of these.

Essentially, we're just going to put our wires inside. They're going to need to be a little bit shorter, I'm sure. But this just presses inside here. Just twist as you push. That's nice. I'm going to crimp it down. Right in the yellow there. It's important to make sure you've got a little bit of metal on the inside there, coming up past where your crimpers are going to be. Just going to crimp this down. Give it a nice little tug. Ooh yes, that's much better. You always want to make sure you give it a tug because if you have a loose connection there, what's going to happen with your LEDs driving down the road? Flick, flick, flick, flick. Okay. Do the same to this one. Okay. So this wiring that goes from the front all the way up by the battery, down and under, along the frame, up along here, and now all the way over there, just isn't quite long enough. And that's bound to happen because you know why? Maybe they weren't really planning on people putting pods in the back of their truck, or car, or whatever you're working on, right?

So we're just going to do something very simple. We're going to get ourselves a little bit of extension wire. We're going to go with approximately the same gauge wire as what we have, the closest we can get and we'll move along from there. All right, so we grabbed ourselves some extension wire. Just going to come right over here. This wiring, it's good to notice you've got writing on one side and no writing on the other side. So you can pick which side you want to be positive. And then just remember we'll go with writing positive. Take it, put it right inside the connector, get it in there as far as you can. It's super important to make a great connection here okay. It's going to go right like this.

Give her a nice tug. That feels great. Let's do this one. This is the plain old black wire and it's going into the negative. So we have both of our black negative wires for our pods going to the plain old black part of the extension wire. Both of our red extensions for the pod there go to the other side. We'll just trim off this. This one. There we are. We're going to go with something as simple as a little bit of electrical tape here. It'd be nice if you can get some shrink wrap over these. If you have access to that, then that's great. For me I'm just going to use a little bit of electrical tape. It's something that everybody has access to. Well, I would like to think most people have access to electrical tape. I don't want to say everybody because how do I know. We're going to make sure that these two split off.

Just rip that off. Rips very easily. Here we are. We have no exposed wire. The connector is nice and covered up. It's not waterproof. It's water resistant. It is what it is. All right, so now we're just going to connect it to our truck, then connect it to our light pods. Down the road we go.

Thanks for watching. Visit for quality auto parts shipped to your door, the place for DIY auto repair. And if you enjoyed this video, please click the subscribe button.

Tools needed for replacement:

    Materials, Fluids, and Supplies

  • Electrical Tape
  • Wires
  • Wire Butt Connectors
  • Heat Shrink Tubing
  • Wire Ties

  • Pliers, Cutters & misc Wrenches

  • Wire Cutters

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