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Choosing the Right Trailer Wiring

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Choosing the Right Trailer Wiring

Hey, everybody, Ryan here at etrailer. Today we're gonna be talking about how to choose trailer wiring that's gonna be the proper setup for your particular application. This'll primarily be geared more towards the vehicle side but we will touch base on the actual trailer side as well. But when it comes to actually picking out what's gonna be right for your situation a lot of people get overwhelmed and confused and rightly so. There's a lot of different options and things to pick from. So the goal today is to kind of break those down, simplify them, and hopefully get you going in the right direction.

As far as the types of wiring we're gonna be talking about, we're gonna have 4-way flat-type wiring, 7-way round, there's a 5-way flat option, and then we'll even talk about kind of some of the ins and outs adapters and things like that that you could use in certain situations to allow you to get the job done. But with the 4-way flat probably being the most popular and what the majority of you guys are gonna need why don't we go ahead and just start with that. What the 4-way flat type wiring is going to do is give us essentially just our lighting functions, right, enough to be able to keep us safe and legal. And so with the 4-way you'll get your turn signals, your brake lights, and your tail lights. So you'll have all your bases covered there.

And essentially a 4-way, this is really common for kind of your average type of trailers, you know, your smaller utility-type trailers, smaller boat trailers, things along those lines. And a lot of times these will even work for, there's certain cargo carriers or lighting kits you can get for cargo carriers. This type of wiring will power those up as well. That's really about it though, as far as what the 4-way wiring is gonna do. It's pretty simple, right Not really a whole lot to it.

The thing that I wanna elaborate on because it seems like a lot of people struggle with this, is making sure you get the best kit for your particular car. 'Cause there are a couple or few different configurations and this is where you definitely want to use our fit guide. Make sure, you know, to punch in all the information correctly, that way you have something to work off of and be able to choose what you actually need. So we'll have factory tow package type deals where essentially they just plug into a connector. Then you'll have powered converter type ones which will tee into the back of your tail light connectors and they'll have a dedicated power source from the battery.

And then you'll have some universal ones which are essentially the same as this. But instead of having custom style plugs for your tail lights, they'll just be a bare wire and you'll have to splice those in. But those are relatively uncommon. Probably one of the more common ones is the factory tow package plug, especially on these late model cars. Just because it says factory tow package don't automatically assume your vehicle don't have that because it doesn't have a hitch on it from the factory and things like that. Becoming more and more popular now for a lot of these manufacturers to essentially have the wiring already back there for you where you can utilize it and just plug this in and it makes it really simple. Manufacturer did a lot of the hard work for you and, you know, it'll get you your 4-way signal. So definitely double check that if a factory tow package is an option for your vehicle through our fit guide. Take a couple minutes, check and see if you can't find the connector plug. A lot of times it'll be located right underneath the vehicle by the back bumper maybe just inside of the hatch. So chances are pretty good if that is an option we probably have a video on it and you could use that to kind of get you going to help you locate that plug. If you ended up checking and you don't have that factory tow package plug or it's not even an option for you, this is where this style of wiring would come to play. It's like I said, it plugs into your tail lights and you'll run a power wire up front and, you know, it'll get the job done. Works just fine. We do a ton of them. But you do again wanna make sure you have stuff entered in correctly because even with these, in some cases, you know, you wanna make sure you're getting the right thing. So for example, this is for a Chevrolet Equinox, the late model Equinox. The higher end sub models have LED tail lights the other ones have incandescent or kinda your standard style bald tail lights. And that matters, right Because those tail lights have different type of connector ends. So you know if that's an option and our fit guide, you know for different types of sub-models or or things like that. Be sure to make sure and and check your vehicle to see what you actually have. That way you can get the wiring the first time. And in terms of that universal kit I talked about you mainly see those on higher end, kind of European style cars. You get a lot of the Audi and Mercedes and BMWs and things along those lines that there's not a custom kit for. You know they're just not super popular and that's where that universal type one would come into play. With those, it kind of is what it is. You will have to splice into your factory wiring. Like I said, they won't have a custom connector on it. It kind of is what it is. If you want the wiring, that's what you're gonna have to do and a lot of times take your time, you never really run into any issues. There are some kits available that just use snaps where they'll snap over the factory wire. Those I haven't had great luck with. It seems like the signals very finicky and and works half the time. So if it we're me that was my scenario, I would get the splicing kit. Take your time, do it right and you'll be good to go for quite some time. Well regardless on what your vehicle has from the factory whether it be a tow package plug or not, there's gonna be a solution for you to allow you to be able to have this 4-way flat wiring. But kind of moving on, we'll go ahead and kind of jump into the next popular type of wiring which is a 7-way round like this. The purpose of a 7-way round type connector is to allow you to plug into this type of trailer wiring. So if your trailer has this style end on it this is what you're gonna need. That way you can plug them two in. And what this style is gonna provide you with is your basic lighting functions your stop-turn tail lights, but it'll also give you the ability to run some additional signals back as well. One of them being electric brake output, another one being a 12 volt auxiliary power, and the other one being your reverse lights. This style of connector is gonna be more popular on larger type trailers, okay Campers, goosenecks, fifth wheels, larger utility type trailers, enclosed trailers, things of that nature. And a lot of times you'll see them on those larger type trailers because many of them will be equipped with electric brakes to help slow you down and other batteries and things like that that you can use the 12 volts auxiliary power that this provides for. If your trailer has this type of wiring, something like this, a 7-way round is is what you're gonna need. And so when it comes to picking out a 7-way wiring for your vehicle it's kind of similar to that that what we just talked about with the 4-way flat. Some vehicles are equipped at the factory tow package plug and a 7-way is available where it'll just plug in and you'll be good to go. So you see that on a lot of the late model trucks, bigger vans, you know, larger SUVs. So that's always an option for you if that's available definitely be the way to go cause set you up really quick. If not, there's a couple of things that you're gonna have to do to allow you to have a functioning 7-way. If your trailer does not have electric brakes or you don't need that 12 volt auxiliary power. So if your trailer don't have a battery or something on it that can be charged while you're towing it or you don't need reverse lights. A simple adapter like this one here would get the job done. Now you are gonna have to start out with a 4-way flat, okay So all these types of 4-way flats are gonna be a good starting point to build off of. So get the 4-way flat and then you can build up to a 7-way with some of the parts that we're gonna talk about. So, if you don't need the brakes or the 12 volt simple adapter this will just plug into your vehicle's 4-way flat wiring and just give you the bare minimum lighting signals. I do like this style of adapter though cause you get the 7-way around and then it still maintains a 4-way flat as well. So if you got different types of trailers you're able to hook up to them. Now with that said if you're gonna be needing a brake controller, so you plan on on putting a brake controller in your car and a factory tow plug isn't an option again you'll have to build off of a 4-way flat kit. Like I said, any of these will work and then you'll have to get into some more parts and we actually carry it's called the universal brake controller install kit. That's what you're gonna need to allow you to get you know, all your, your lighting functions your electric brake output as well as your 12 volt auxiliary power. In terms of how you're gonna live with your wiring or how it's going to affect the looks of your vehicle. It'd be very minimal in some cases. On a lot of smaller SUVs and stuff like that your wiring can actually stay inside. So I talked about, you know the factory plug is sometimes in the hatch, you plug it in you can leave it stored in there, drape it over the back when you're ready to plug your trailer up to it. Some other wiring kits will only be mounted outside. It's just gonna kind of depend on, on your particular application. You do wanna mount it up outside, you can always grab some no drill brackets and and some 4-way flat brackets that way you can mount this up real nice if you want to. You know, you can even go as far as to grab wire loom if you want it and cover the wires up to make it look a little more pretty. But that's entirely up to you and that's gonna kind of bring me to my next point. I'm gonna go, I said a lot of times the connector ends on the trailers especially end up getting chewed up just cause they're in the elements. To help prevent that you can always grab dielectric grease every now and again put a a coating over the terminals and that'll really help prolong the life of it. When you kind of find yourself in a little less common scenario but this definitely still applies to some people and that is if you don't need trailer brakes, right you don't need a brake controller but you still need that 12 volt auxiliary power to run let's say a battery on your trailer whether it be on a winch, something like that. Pop-up campers are really popular. A lot of times those won't have trailer brakes but they will have a battery that way you can operate you know, your uprights and your pop outs or if you're wanting to use a a wireless type brake controller. The current Echo for example which plugs into that 7-way connector if that's what you're trying to do there's another kit that we carry here at etrailer and it's similar to the brake controller install kit just comes with a few less components and what that'll do is allow those lighting functions to work as well as get that 12 volt power back here. That way you can charge up your battery on your trailer and and get all that going. Just wanna touch base on this real quick just to avoid any type of confusion. So if your vehicle is equipped with that factory tow package plug and a 7-way is available for it where you can just plug it right in, regardless on what you're trying to do that's really all you're gonna need. So say if it has that tow package plug and you're wanting to use a brake controller you're not gonna gonna have to worry about those other parts that I mentioned, right Because the factory already have all that stuff ran for you. That'll hold true with the 12 volt auxiliary power your reverse lights and so on. So if that's your case and you are trying to use a brake controller you'll have to pick one of those out. We got a ton of content on that and a lot of times they'll be underneath your dash a factory plug that that brake controller can just plug right into as well. So just wanted to avoid any confusion and not mislead you into thinking well if you got the factory tow plug, you're still gonna need all these other brake controller install kits and stuff and, and that's definitely not the case. For those of you that do end up having a factory type option, as far as the 7-way goes, you need to be able to tow a trailer that has a 4-way flat on it. There's an option for you as well. And that is using an adapter. So that's what we got going on here. We got the 7-way back here but we're pulling a trailer with a 4-way flat, you can use an adapter like this here. So that'll plug into your 7-way and then your 4-way flat end on the trailer can plug into that and you'll be good to go. You'll get all your lighting signals. And that even holds true for adapters that have a 5-way flat end on it as well. So that's available which is gonna kind of bring us to our next point. Why don't we talk about the 5-way flat and what you can accomplish with that. When it comes to the 5-way flat, this isn't super common but there are quite a few people out there finding themselves needing this style of wiring. And so what a 5-way flat's gonna do is just give you your basic signals, so your tail lights or your turn signals or brake lights, but that additional pin is gonna be for a reverse light circuit. And so you'll find this style of wiring primarily on boat trailers that have surge brakes, you know for their trailer brakes and you know you can use a style too let's say if you wanna put reverse lights on your utility trailer, something along those lines. Now that's where this will come into play and I've yet to come across a 5-way flat type kit that's custom fit for your particular vehicle. It might be out there, but I've yet to see them. They're not really a big deal. So if you're wanting to, to be able to use this what you're gonna have to do is build off of your 4-way flat wiring. So I talked about, you know there's tons of options as far as this goes. This is what you would need to kind of build off of and then you can use kind of a, I guess you'd call it an adapter like this one here. So the way this would work you'd have your 4-way flat set up on your car and to convert it to the 5-way that would plug in you know, to your car's wiring or vehicle's wiring. That'll give you that 5-way flat end and then what you're left to do is be able to hook this up to your vehicle's reverse light circuit, that would take the circuit from there. And so whenever you put it in reverse this will get power and send it out to your trailer. Kind of moving on, I want to talk about in bed wiring. And this is really only going to apply to those of you that have a big truck like this and that pull a a fifth wheel or a gooseneck type trailer. So with your trailer being hooked up in the bed, one of the issues you run into when you go to plug it in is you're gonna have to drape it over your tailgate and go down to your bumper and plug it in. Well then you scratch up your tailgate could potentially damage your trailers wiring. Not to mention too, you know, it's about safety. The chances of that plug coming undone is a lot higher. So to combat that, you can always get in bed wiring. So where your connector plug will be in here and allow you to plug in your 7-way from your fifth wheel or your gooseneck. And the way this works is this kit like this will just tee into the connector plug on your bumper. That way when you're pulling a a trailer that gets connected in the bed, you'll hook it up into there, but if you go to pull your bumper trailer, your bumper pull, you'll still be able to utilize that one on your bumper there. There's a couple things to look out for whenever getting in bed wiring. One of them is the type of material your bed's made from. So like a lot of the Fords, for example, have aluminum beds. If that's your case, make sure to get the kit designed to work with aluminum beds. A lot of times they come with different types of hardware that way you don't get corrosion and things like that going on. And another thing to look out for, a lot of the later model trucks too like these TMS here will have a knockout panel. So the whole, really in bed connector should go is there there's just a, a panel covering it, so you know, a kit like like this Curt one for example, it'll come with a thing to pop in there and then give you your your 7-way like that. So it really does a good job of keeping things clean and looking factory. So just a couple of pointers there to to think about whenever you go to pick out your your style of wiring. That will kind of wrap up and and conclude the vehicle side of things. The biggest takeaway that hopefully you get from this is to you know, ask yourself what you're gonna be doing. You know, what type of trailer you're gonna be pulling, what that trailer's equipped with, and things of that nature. That'll determine what style of kit you need, and then from there, you know again be sure to use our fit guide. Enter your vehicle in and see what's available. And you might have to do a little bit of homework on your side too to see if you got that connector plug or if you need the other style of tail light plug and wiring to make sure you get what you need the first time with the vehicle side of things out of the way let's just kind of quickly touch base on the trailer side. Talk about some of the common things that we see. So when it comes to trailers, you know, people are hard on them and especially the connector ends usually end up getting damaged or corroded, you know, they end up laying on the ground, whatever the case may be. So if your trailer's lighting was functioning and then you suspect the connector end going bad, there's no reason to replace all of it from here back. You know, you can always just replace this end or pigtail what I like to call it. And so whether you have a 4-way flat like this, you know there's gonna be an option available and a lot of these come in different lengths and stuff but you'd be able to splice that in and you would need some buck connectors to make that happen. So that holds true with the, you know, whether if your trailer has a 4-way flat, a 5-way flat, those pigtails are available as well as the 7-way round as well. So regardless of what end you need we're gonna have something that'll work for you. Something that's getting more and more popular now is actually adding trailer brakes to trailers that didn't come equipped with them originally and that's what Joe's actually doing here today. He's putting some brakes on the trailer to make it a little bit easier to stop but if that's what you're trying to do so you know if that's your situation that trailer you had is originally gonna have a 4-way flat connector on it, right Well once you install your brakes you're gonna have to change a few things as far as the wiring goes and to get it all wired up properly, a really good starting point is this kit for etrailer here. It gives you a junction box and a 7-way end here. So you get this set up on your trailer and then you'll need some wiring as well to run from your junction box to your trailer brakes. That way when you're in your truck or your vehicle and you hit the brake, the brake controller sends power out, send that power through here, through the wires to the back of the trailer where the brakes are and allow you to apply those trailer brakes. For those of you that plan on adding brakes to a boat trailer, your situation's gonna be a little bit different since boat trailers use surge brakes. All that electric brake stuff really isn't necessary. So the way these surge brakes work, whenever you're pulling this and you hit the brakes in the truck that force will push a trailer forward and kind of push the actuator in and and send hydraulic fluid back to the trailer brakes. So you really don't need an electric brake signal, so to speak, but I would highly recommend using an electric lockout type actuator. And that's where a 5-way flat, that's going to come into play. So when you have this set up and without an electric type actuator, what can happen is whenever you put the truck in reverse, the brakes are gonna try to apply and that's can be a big pain when you're trying to go down the ramp or back in your driveway or whatever. So you can, you get the electric brake actuator, I'm sorry the electric actuator. You get a 5-way flat and that reverse wire will actually tie into the actuator cylinder here. And when you put it in reverse it will, you know, prevent this from locking up. That way you can actually back the truck down the ramp or or into the shop or, or whatever the case may be. I did my best to kind of cover all the popular scenarios that a lot of people find themself in. And so, you know, hopefully my end goal here is to give you the information and insight you need to get you going in the right direction and get either your vehicle or your trailer set up and be ready to tow.

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