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There's something about wiring that just freaks people out. I think many people who learned about cars from their dads, or older mentors, were warned never to mess with the wiring.
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0:00 Custom Automotive Lighting Wire Harness
0:04 Cutting Wire to Length
0:32 Components of the Harness
0:55 Why Make a Wire Harness?
1:40 OEM + Aftermarket Connectors
2:35 Tools for making a Wire Harness
3:27 Getting Started on the Harness
4:42 Why these types of Connectors?
6:07 Stretching out Heat Shrink Ends
6:55 Alternative Way to Solder Connectors
8:31 Heating the Heat Shrink
9:04 Preparing for Wire Loom
11:02 Braided Wire Loom Pipe Trick
13:20 Inch by Inch Braided Wire Loom
14:11 Heat Shrink the Wire Loom
15:28 Adding the Second Connector
17:41 Last steps for the Wire Harness

In this video, i'm going to show you how to make a custom automotive lighting wire harness all right. So i've got all four colors that i need. I've got my show mode colors, which are green and orange. I'm going to take a full arms length because i'm just over six feet tall, so that makes this about six feet in length and i want to go another foot past that.

So this should give me about the length from the passenger over to the driver's side of the car i'm using scissors use whatever you want to cut wire, sometimes that bugs people when i cut wires with scissors, let's just dive in i'm, going to show you the Components that we have right here and we're going to use stuff, that's a little bit different than what you would see on something like an engine management wiring or like a how to build a full vehicle wire harness we're not going to have to follow such strict Standards - this is just going to get you from start to finish in as simple and short a time as possible. I like that i kind of picked that up makes me more relatable and last but not least before we get into it. I just want to say why we're doing this, the reality is, if you look at a lot of custom lights that are being built, they have modules. They have all these extra wires stuff that freaks people out.

You don't want to see this if you order a pair of custom lights having stuff like this, come out the back of the lights. What are you even supposed to do with that? So what we're going to do instead is we're going to be working with little connectors like this and i'll show you what that would look like coming off the back of these lights in just a second one thing that you're going to notice is i'm just going To use some very kind of basic 18 gauge wire here, this is not hardcore high horsepower race engine management, wire harness like it's just simple stuff - we're just gon na send 12 volts from one part of the car to another part of the car, and it doesn't Have to carry a bunch of amps, so let's dive in i'll break it down for you. If you look at the back of a stock set of lights a lot of times, there are a bunch of wires already there. But what comes to the inside of the car is just this one little connector it just plugs right into the vehicle harness there's.

Nothing really scary about that. There's nothing to do wrong and that's exactly the way that we're going to approach our custom wire harness where one half of this connector is going to be attached to the actual light. So if you can imagine when you look on the inside of the car, it's just going to look like that. One connector that handles the stock function and then you're going to have another connector that handles all of the cool custom functions that we've built in and all you can do is plug it in one way.

You can't do it the wrong way at all and here's. Why there's five different little pins inside of this, but i can't do it upside down. I can't do it anyway, except for the way that it's supposed to go together and it just twists on tight. You got a nice waterproof connection there and we're good to go.
We have everything done. It's all been wired up. Let's talk about the tools that i'm going to use for this, i'm going to be doing a bunch of soldering, and so i just want to use these helping hands from quad hands to just keep the wires in place so that it's not difficult for me, as I'm trying to solder things up when i solder them up, i'm going to cover all of that stuff with heat shrink and to get the heat shrink to cinch over those wires into place. We're just going to use a heat gun.

If you don't have a heat adjustable heat gun, i think this thing is like 30 bucks or something on amazon grab. One of these - it just makes sense that sometimes you don't want to blast it with full heat, so heat guns, a awesome tool for custom lighting, automatic wire strippers, these from capri tools are killer. These things save me a ton of time, they're easy to use, and it just makes everything fast and last i don't know if you have some of these just some regular scissors is going to do the trick. All of this stuff is going to be linked up below i'm going to get it into place and we're going to put all this stuff together for our custom wire, harness first thing that we need to do.

We've got our seven foot section of wire, we're just going to unroll all of this and then our five foot wire as well, and bring the two ends together. Okay, now the reason we're gon na do this is because we have one wire that we want to go down to one headlight and then over to the other headlight so step. One is gon na be to strip the ends of all eight wires that we have here and then we're gon na join them by just twisting those ends together. So we'll start with this orange wire, i'm just gon na pull the ends off twist these guys and then put them right back in the quad hands so that it's ready for solder next step is going to be we're going to solder right to them.

So we want to have a little bit of solder on the tip and then we're going to push it into the wire, and now the rest of the solder is just going to be sucked right into the copper strands. I hope this makes it pretty clear how easy it is and how fast you can solder up these wires. This is something that you might want to do if you're going to do a lot of wiring clean up as you go, it's so annoying to have all these little bits of wire everywhere after okay. The reason that we did that now is because we want to add the connector right to the ends of these wires, so we're gon na take our first connector and explain why we use the one that we do right now, so this guy's got a little twisty On it - and this can come off - we don't want that to be damaged in any way, because then these things aren't going to lock together, because it's so just fast.

It's just easy to use. So i want this part right here specifically to be connected to the wire harness instead of the light, because the light could be set on the ground somewhere. Somebody could accidentally step by and step on, the wire harness break that i think this one makes sense if we have to choose between that side or this side put the one with the little sliding locking connector on it to these actual wires themselves. So what we're going to do is just solder each of the wires that correspond to these colors directly to this, and for this orange one we're going to go right to yellow.
I want to put my marine heat shrink, which is it's going to have a adhesive on the end, so it's going to seal these against any water that could potentially go in and touch the bare metal where we solder it to these. But i need to have a little bit more length on these wires, so i could slide the heat shrink down. I'm just going to make a little slit on this and be very careful not to mess up the wires, i'm just going to open them up ever so slightly. That is great.

Now i don't need to cut this excess off, because i'm just going to lay it back into place. All i want it for right now is just a little bit of extra length so that, as i slide, this heat shrink over. It's not super close to the heat source right here, which would actually make it shrink up right where i need it to be fanned out, and on that note let me show you a little trick, so i want this heat shrink to fit really really tight over These wires, the problem is it's not quite big enough. I mean i could kind of work it on there, but because this is three to one heat shrink and it's got the adhesive on the inside.

If i take these really small pliers, i can kind of fan it out a little bit. You don't want to go too much, but if i do it just a little bit like that now, when i go to slide it over into place, it just completely covers that and it will shrink right back down and the adhesive will seal it tight. Now i do want to make sure that these things have enough solder on the ends, so i'm going to add a little bit extra to them right now, just so that they mate really really well with the wires from the harness. Now we're ready for our heat shrink to slide down, and i have fanned out the ends of all of these guys and last we're going to start connecting our wires up.

Now, i'm going to show you something this has actually been twisted together in a different way. So if that absolutely destroys you inside, and you cannot see a twisted and soldered wire laid over and then soldered to another wire, and you really have to have that hardcore mechanical bond. This is what a lot of people like to do as well, and i'm not one of them. They fan out the wires.

You can actually strip the wires a bit longer, which is one of the big issues that i have with it. You basically push the ends of the wires together and then you start to twist them and you make a mechanical bond before you ever add any solder to them. So these things are already kind of holding tight to each other. The problem is, if you're doing this on a ton of wires, it can get pretty insanely tedious and you can do a much better job than even that, but the trick that a lot of people like is what i'll show you right now.
So since i already have this mechanical bond, i am going to just slide over this connector, which is heat shrink, and it has solder in the middle, and i want to have the solder right in between those two wires and then i'm just going to blast it With heat personally, i'm not a fan of these things. A lot of people swear by them. For me, i know i've got decades tried and true using solder and marine heat shrink. I'm just gon na keep doing it that way, but again, if soldering it the way that i just showed you on this wire harness bugs.

You then just go ahead and do it that way: you'll notice that there's a fifth wire: it's because these are five pin connectors. So i don't need this wire, i'm actually just gon na clip it, but first let's hit these guys with heat so that they get that nice seal all the way around them because of the internal glue inside of the heat shrink itself. It's actually kind of nicer to do it on the ground, because the heat doesn't just blow right past it. It kind of concentrates, bounces off the ground, and then it gives that 360 coverage.

So this is what we wanted and we're going to add. Even more heat shrink over the top of this on the next step, all right, so we're just going to cut that guy there now. What i want to do for this next step is i'm just going to add a piece of heat shrink that goes up right over here and then we're going to slide it back over after we have the wire loom and everything else in place. So, let's start with that, first all right, so i think this is about a half inch heat shrink right here.

So i'm just going to cut this thing down to about that long and then we're going to go ahead and slide it all the way down. All of the wires and have it resting right here and waiting for the next step, i'm going to start with the long side. Add the other, shorter wires. Take this all the way down to the end.

Okay, now next step we're going to add our wire loom, and so to do that, we want to make sure that we have a left and a right side, a short and a long side for all of these wires. Now the other thing that we want to do is make sure that we don't have them all tangled up or anything and again we're not going to twist these or do anything fancy with them. I just want to make sure that they're separated and that it's a nice clean separation, instead of them being kind of slightly twisted up anywhere along the way and as you can see, i've got just a couple wires that are a little bit twisted up. So i'm just going to pull this one black wire out, set that to the side, and now there we go it's nice and clean separation between the two parts and we're going to start putting little pieces of tape on here to group these up.
This is instead of twisting it like you, would do with some sort of like a badass concentric twist engine management harness. We don't need all that just some tape. This is a little trick that i've been using for a lot of years, just because i've had to make so many wire harnesses. But when you're going to cut a bunch of pieces of tape, sometimes it just makes sense.

Just use your fingers and then just cut little pieces like that, and then you can just go through. You've got everything that you need to at least get this five foot section done, do them in about every foot and a half or so not because of anything scientific, but just to keep the wires tidy to keep them together. One of the next steps that we're going to do is run some loom over these wires, so it just makes sense to keep them at the same lengths. Not let them get bunched up and not overthinking.

It, i think, is a big win. You want them to be taped somewhat close to the ends just to make that next step easy too and you'll see why, in just a sec, okay, now we're gon na do the same thing on the other side. Okay, this is dope. This next little section is gon na be cool, so i'm putting the last piece of tape on our long section on our seven foot section, and now, i'm gon na take this little clear pipe now this is you're gon na have to find something that works exactly For the types of harnesses that you make - and you do not have to do this i'll show you the slow way after this, but i think this is badass.

My buddy jay showed me this and it just made so much sense. She was gon na feed that through this little tube a little bit - okay, full disclosure - i just messed this up, because i didn't put this piece of tape on there. So this time i'm gon na put my wires down there and then i'm just gon na put a little piece of tape that just holds ever so slightly onto this tube, as well as onto these wires, and the reason is when i start pushing this thing into Place it is going to put a little bit of pressure on those wires and they're going to want to slip off so this time, i'm going to start by putting this wire loom this braided wire, loom on, and i'm just going to slide it on this tube And it makes it so much faster than trying to go inch by inch on the actual wires, because if you see it's just going down that whole section and it's doing it without me - going inch by inch, it just got it over all seven feet and then At the end, here i can just take off a little bit of tape and now we're all good to go so. I've got seven feet of wire, loom completely brought all the way down to the end, and i'm even gon na reuse.

This little piece of tape right here at the end, to make sure that it stays nice and tidy before i put the piece of heat shrink over the top of this, and that's what i'm going to do right now. So this is my heat shrink. I am going to cut it in half and use one half for each of the wires we're going to do the same thing. This is just going to go all the way down to the end, and this braided stuff can get really frayed out and gnarly.
So this helps out a lot to make sure that this thing stays looking nice and there. We are nice and tidy right up against where these wires are going to go into this connector and then the last step is after we have the other heat shrink and loom there we're going to slide this over and it'll just look nice and clean. So, let's now do the slow method of inch by inch putting the wire loom over these wires, and this starts off pretty tedious anyway, because you have to get all four wires in the loom itself and then it's going to go for a little bit and it'll. Stop pushing in and we're going to have to start sliding it up on one part and then inch warming.

It all the way up literally inch by inch. So this doesn't seem like it's too bad of a deal. But if you're doing this for like 50 feet of wire, that sucks that's gon na take forever. This was only five feet and it still takes a good long time and you just feel dumb, like you're, just wasting your life away.

While you do it that tube trick can be very nice, it can speed things up big time, all right, i'm going to do the same thing, cut a piece of tape and then we'll slide over the heat shrink in a second. We will finish up this end of the wire harness okay. Here we go so i'm going to take these two bits hit them with the heat gun. You got ta, be careful not to hit the actual braided loom.

So you got ta watch how much it's shrinking down! That's also why the heat adjustability can help out big time with these heat guns. If i hit this with the heat gun, it'll just melt right through that wire loom, don't want to prove that to you right now and pull this heat shrink over the top of all of it, and that should give us not only a nice better. Looking connection, it's actually stronger now, when this thing is still really hot, the point of weakness is basically right before the bunch of soldered up wires. It's just right here, but that honestly does get a lot firmer after this thing.

Cools down and the reality is, is now we're good to go like this thing is already all set to connect to the first tail light, and it just looks so much cleaner than if we had a bunch of individual little wires or little connectors or anything like That and they have these things in bigger bunches, so you can get them with four pins or five pins, or i think i even have some that have eight pins on just a little connector like that. Okay, let's do the other side and then this wire harness is ready to go. This is a mistake. I've made a lot of times.

I forget to pre-heat shrink this wire loom and then i make all the connections and then i'm like crap. Now i don't have a nice looking connection at the other end and look at that mess. That's what you're left with tape and that you don't want that. It's good to just remember to put that piece on there: okay, so i'm going to now strip the ends, and i don't need to have this little piece of tape on here anymore, but what i am going to do so that i don't accidentally mess up the Wire loom is, i am going to tape the wire loom itself, the braided loom down further down these wires and just to make sure that i'm being clear about this, this is the other end of the long wire right.
So this is going from passenger light over to the driver's side light with a little bit of extra slack to get anything from one side of the car to the other. And then the part that we're not messing with is the one that would be going up to the battery. If that makes sense now this only works if the battery's under the hood next to the headlights. In this case, it is because it's for a gtr all right, so we're just going to do the same exact thing as the other side, but this time it's a little bit easier because we don't have two wires to twist together, and so that means this will Go quite a bit faster, i'm just going to throw this solder right to the ends of those.

Now we're done soldering and last. We just have to tin the ends of these again before we put all those wires together. All right last is our heat shrink, and this harness is ready to use okay super important on this next part. I want to get all the slack out, so i'm going to come all the way down here to the far end of the seven foot wire and just pull tightly to make sure that it's pushing all that braided loom forward.

And you can see it even went so far that it started to cover up where we just put those uh those little bits of heat shrink on there and that's good. Now. We're gon na put a piece of tape right on the top, so that that fraying out never has a chance of slipping out of the heat shrink and we're ready to put the last little bit of heat on there boom. We're all set this last bit.

I'm not really too super worried about, because i'm gon na make a few changes, but i did already put my heat shrink into place so that once i've trimmed these exactly how i need them after i connect them to something like a remote control or something at Least, i've got everything here and ready, so this guy is ready to go. I could technically sell this thing as a ready-made harness with something that anybody that's already built. Some lights could easily just pop this little section off solder it onto their custom light and now the functions that are built into that thing. Custom can be controlled and you can hook them up to something like a little uh switch controller right here with the remote control.

This is how i'm gon na end up doing this is. I will have one of these little boxes. That's got all of these four buttons on there and i'll be able to turn on show mode 1 and show mode 2. Simply by connecting these two power wires to the output on that switch box, you could do it any way you want.
You could do a bluetooth setup, this could be used to control something that's rgb, so it's got power and then it's got red, green and blue. You can do anything you want with it, but just knowing how to make a harness like this. That doesn't have to be some hardcore engine management style. It's not mil-spec, it's getter done spec and it looks good - and this thing right here that you just saw me make is worth 200 bucks.

Why? Wouldn't you want to know how to do that yourself? So i have a bunch of paid courses that people can take on my website, but this is just a free gift that i want to show you, because it's something if you work with sequential specifically ghost lighting sequential modules, you'll want to know how to make a Harness like this so make sure you're signed up below for sequential squad. That's my free group. It's a bunch of us that design a bunch of cool lights together. I hope you enjoyed it and check out this video.

If you want to see more about ghost lighting.

By Chris

9 thoughts on “How to make a wire harness”
  1. Avataaar/Circle Created with python_avatars Brian G says:

    Love the tutorial.

  2. Avataaar/Circle Created with python_avatars Fatfreemilk says:

    Got a dumb question, how do you make the new headlight indicator strips you installed light up/flash when you unlock the car.
    I’ve got it powered by switched 12v but that only allows power when the car is on. Direct to the battery works, but the lights are always on. What is a better way ??

  3. Avataaar/Circle Created with python_avatars 280zone says:

    Since I finally got you to try the wire stripper, I'll throw a few more tips your way.
    When splicing multiple wires I like to stagger them to minimize the bulkiness.
    Grab a heat gun that has a wrap around nozzle for heat shrink tubing.
    Mount the heat gun to the wall facing down and you can switch it on and hold the wire in place. I added a foot switch for added ease of use.
    When you cut your wire loom material, put a slight singe on it to melt those together so they don't start fraying during install. This takes some practice, because if you singe it too much it won't expand as much to go over the wires.

  4. Avataaar/Circle Created with python_avatars Sean Pamer says:

    Nice step by step tutorial and I especially like the tips for making it easier.

  5. Avataaar/Circle Created with python_avatars Fablighting says:

    Real awasome video , I had to check to make sure Im on youtube not Kajabi🙈🤣💚

  6. Avataaar/Circle Created with python_avatars FlyRyde says:

    Workin n the blog post now 😅

  7. Avataaar/Circle Created with python_avatars Garforce II says:

    water resistant, i’m sure if you submerged it. it would get permeated by the water

  8. Avataaar/Circle Created with python_avatars Kustom LED Creations says:

    Good stuff

  9. Avataaar/Circle Created with python_avatars Garforce II says:

    question, where do you get your wire, is it all copper?

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