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Roadmaster 4-Diode Universal Wiring Kit Installation - 2017 Subaru Crosstrek

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How to Install the Roadmaster 4-Diode Universal Wiring Kit on a 2017 Subaru Crosstrek


Ryan Hey everybody, Ryan here at etrailer. Today on our 2017 Subaru Crosstrek. We're going to be showing you, how to install the Roadmaster diode wiring kit. But before we do that, I want to check it out and make sure that this is something that's going to work for you. Ryan So before we get too carried away, really checking the diodes out and how they work and everything like that. I figured it'd be useful just to kind of touch base and refresh yourselves on the main components that we're going to need to flat tow our Subaru down the road in the first place.

Ryan There's going to be a total of five, that we're going to need. The first one's going to be our base plate. And what that's going to do is provide us with a solid and reliable connection point, That way we can hook our tow bar up to it. Ryan That tow bar is going to be the second component. And this is going to be the physical link that actually connects the front of your Subaru, to the back of your motor home.

The third main component will be safety cables, and these are pretty straightforward. These are just they're in event of an unlikely disconnect. They're going to keep everything paired together. The fourth main component, is going to be your tow bar wiring. And what that's going to do is transfer the lighting functions from the back of your coach, to the back of your Subaru.

Keeping you safe and legal. And last but not least, the fifth main component is going to be a supplemental braking system. And what this is going to do is hit the brakes in your Crosstrek, Whenever you hit the brakes in your RV, helping to bring you to a complete and more predictable stop. So this is a perfect example on how the wiring's going to work. You could see we got the left turn signal, going on our motor home, and that is sending it back to the left turn signal here on our Subaru.

So not only we're we get our left turn, but our right turn as well. As well as our running lights and our brake lights. So we have all of her bases covered as far as that goes. So when it comes to wiring, you know, this isn't the only other option. There's also a kit called magnetic lighting. And we'll kind of talk to, talk about that in a second, but, I definitely think this is probably the best option. And I said it because, we've done a ton of these. And, always had pretty good luck with them. You know, you're not even going to be able to see it or know anything's been changed. Ryan You know, on the car once it's installed. And more importantly, it's super easy to hook up. And that seems like a big deal to a lot of people. You know, they don't want something that takes up a lot of time, and is confusing and things like that. With this setup, once it's on the car, all you're literally going to have to do is just plug it in. So, I mean, anyone can figure that out. Compared to that other type of lighting, that magnetic light, for example, You know, those are, those are kind of a hassle to do. You have to set them up and take them off, every time you're ready to flat tow. Ryan And so you're going to have to stick the lights, you know, they're they're magnets. So they're going to stick up on the roof. You've got to drape wires all the way to the back of your motor home, plug it in and do that every time. And not to mention, you know, as we all know storage, when you're over the road and things like that, it's a big deal. You know. You don't have a ton of space usually. And using those magnetic lights, you're going to have a big bundle of wire, and lights that you're going to need to store whenever you're at the campsite and, You know, want to cruise around in your Subaru or whatever. So with this kit, it's something you're not going to have to worry about. So whenever you are ready to hook up to your motor home, it's a really simple step. You're just going to take your wiring connector, your wiring plug railer, plug that into the connector, here in the front of your Subaru. And then the other end of the cable is going to run, up to the back of your motor home. So, plug that in. So, I mean, it doesn't get much more simple. But talking about this cable, kind of brings me to my next point. There's several different kits available, and they're all kind of purpose-built. And I just want to kind of go over them to make sure that you get the appropriate one for your particular setup. So, The kit that we're using here today, is actually it doesn't come with a cable or a connector plug, and that's because some of, some of the nicer tow bars actually, come with those components already. And so the kit that we're using, is just kind of the bare bones kit, is what I'd like to call it. You get the wiring and the diodes and a couple of connectors and things like that. And that's because it doesn't make sense to buy, another full kit and end up with two cables and stuff that you really don't need. So, if you have a tow bar that comes with the connector plug and the umbilical, that's the kit that you need. There's also other kits available, that have a couple of different type of cables, if you will. So, one of the kits available actually comes with this type of cable. And it's called a hybrid. So it's coily at one end and straight in the other. Ryan And you're going to want to use that kit, if your tow bar has channels in it. Okay And that's because the straight part of the cable is gonna allow you to run through those channels and utilize your tow bar properly. Now that kit that you could use, if your tow bar has channels is this one. And this just comes with the kit, comes with the straight cable. And again, it works the same way. If you know this one, the hybrid type one, I think this works the best if you're using what's called a high-low adapter. So I think that goes into your hitch and kinda makes it the, you know, the space between the motor home and your car a little bit greater. Because this hybrid cable is actually a little bit longer. So, keep that in mind. But then for those of you that don't have a tow bar with channels in it. You'd want to get a kit like this. So this is just a coily cable. And the purpose of this would be to, you know, it's going to stay nice and tight and high off the ground whenever you're going straight, but then, extends whenever you make those turns and give you the length that you need. So there's two available with this style, this one here, you have a seven to six way round, and then the other one has a seven to four way round. So, whatever you're trying to go for there. This is probably the most common, at least that we see. The seven to six. And then there's kind of the classic, just the four way flat connector, to four way flat connector. If your motor home only has a four way flat, this is probably the correct choice for you. Honestly, we really don't see them at all that often anymore. You know, these are kind of just starting to get a little old. And a much more common is that six way round to seven way. But you know, if your motor home has this, there's still an option for you. But other than that, you know, as far as getting the lights to work on your Subaru, whenever you're towing it behind your motor home, definitely going to be the best option. You know. It keeps your factory wiring protected, since it uses those diodes. And, you know, it's going to be really easy to use. So, what more could you really ask for out of a, out of a wiring kit. Now, as far as the installation goes, really not too bad. You know, you are going to have to splice into your vehicles wiring, not really a huge deal. I'll show you, kind of walk you through step by step and show you how I did it. But I'd say probably the most time consuming part is this routing the wiring from the front to the back. It does take up a little bit of time, so be prepared to do that. But, other than that, why don't we go ahead and pull them to the garage and, hook this up together now. Mechanic To begin our installation, we're going to be here at the front of our Subaru. And obviously we have the front end taken apart here. And that's because we're doing this the same time as we did our base plate. It makes it a lot easier. But that said though, you don't have to have all this stuff removed. It just takes a little trickier, a little more difficult to get to and see. But, for that said, I took one end of her wire here and have it running close to our mounting point here on our base plate. And what you're going to do is take the rubber dust cover off of your connector plugs, slide that over. Then we're going to separate these wires. So just take a pair of snips. And then carefully cut in between'em. Mechanic Gotta peel these back a few inches. Then what I like to do, excuse me, is just kind of cut the ends off here. Give me a fresh start. And now we can strip back all the ends of the insulation. So once we have all of these stripped back, what you want to do is give them a good twist, make sure the wires are nice and tight. Mechanic And now we can grab our connector plug. If you look on the back of it, we're going to have some terminals. And the way these work is you back out the set screw. Pretty much all the way, try not to completely remove'em. It makes it kind of hard to get back in. But, these are all going to be labeled. And we're going to be working with four of them. This one is labeled TM for tail lights, So the brown wire will go to it. This one here is GD for ground. So the white wire will go there. This one is LT for left turn for the yellow wire. And this one here, our RT right turn for the green wire. So, take the appropriate wire, and, place it into the terminal. Hold it down. And simply just snug up that set screw. So I'll go ahead and repeat that process for our remaining wires. So this is what the back of the connector plug looks like. Once you have the wires hooked up. And with that done, we can take our cover, put it over. At the end, I usually like to come back with some dielectric grease, and, you know, put it over the terminals and tape this up, and seal it real good. But I wait to the very end, once we know everything is working properly. That way, if we have an issue, you don't have to come back in and undo everything. So, for now this'll work. And align that up with our bracket, get our screws going and get this mounted. And once we have this complete here,Mechanic I'm going to start to route our wiring, towards the back of the vehicle. So I'll go ahead and do that now. I'm going to show you the path that I took. I just ran it up through here. This portion I did put on some of that wire loom, just cause it's, you know, kind of going through the smaller opening. You don't want it rubbing up against anything, but, but that said, I just ran it right up through here. Here's where it comes out. And I just started to run it through this opening there. And at this point, what I've done, is cut the white wire in half. You want to do this very carefully, and strip back the insulation. And this end, this goes to our six way connector, there at the front, and we're going to ground that out. So I took on, took a ring terminal, maybe we can crimp this down. And I'm going to use this factory ground stud right there. If you could take a 10 millimeter, and remove that bolt, take our ring terminal here. And get it lined up. We'll take our bolt, and pass it back through. We can just tighten it back down. Once this is tight, you can grab the rest of her wiring, What we wanna do, for the rest of her wiring here. So here's the other end of our white wire that I cut. You just want to peel that off their whole harness. And hold onto this for later, it's ready to use it later. And now the rest of her harness, I'm going to continue to route towards the back. And again, I'll show you how I did that. So I continue to route our wiring. I just simply dropped it down and oop right down through the bottom there. Mechanic So I got our wires routed back. And, underneath the vehicle here, it is where it dropped down. Then I simply just ran it through, this little mount here. You're doing this, do your best to avoid any hotter moving or sharp parts. Ran along our frame rail. Really nothing to secure it to. So I just use some peak clamps. Just to help keep it from bouncing around and everything. But from there, and I want to mention too, there's panels that go up here. You can take them down and just some plastic fasteners and I think a couple of 10 millimeter bolts and drop them down. Well, I got it routed on through there, kind of below our fuel tank. And then right here, I put another piece of wire loom just cause there's kind of a sharp edge right here. And up through there, Up and over or some frame. Drops down through here. So, and when I've done our yellow and brown wire, it's going to go to the driver's side. And what I did was take that extra long piece of white layer that we had saved from our ground and taped till the end of it. And eventually this is all going to get pulled up into the driver's side tail light pocket. Mechanic The green wire and the white wire. I'm sorry, the green wire is separated. The green wire is going to run over to the passenger side and the other end of the white wire. Then I add it on, that's going to go with it. So in our case, a trailer hitch right here, I actually just routed those through the trailer hitch. And so runs, long through there, where it drops out right here. Now what we can do is go up top, get our tail lights removed and get all of our wiring routed up into the pockets. So get the taillights removed up top here, open up your hatch. And we're going to have two 10 millimeter bolts. Those pulled out. Then, we'll just kind of wiggle the light and pull back at the same time. We're going to have a connector to get it disconnected by pushing down on the tab. Usually, not this difficult. There you go. tab, we'll separate it. Set the slide off to the side, do the same thing to get the other one removed. This point, we can get our other wiring up in the taillight pocket. So I just used a pull wire, just dropped it down through the piece of tubing, but you can always use a coat hanger or something like that. It's taped your wiring to it. Mechanic And well, pull it up. What it's getting hung up on here. Let's do this all the way up. Well that slack pulled out of there. And obviously we're not going to need, you know, five extra foot of wiring here. So, I'm just here to cut this about here. And then, you can usher back the insulation. So, I'm gonna separate these wires. Mechanic For the white and brown wire, we're going to take those two ends and twist them together. Nice and tight. Takes the yellow terminal. Pop that over it. Crimp it down. For the yellow wire, you're gonna take the blue terminal. And crimp that one down. And then we can start to prep our factory wires here. So there's this, this is all taped up. I cut this back and I tested these wires, to figure out what signals do you want or wires do you want When I come up with the black wire here with the white stripe. That's going to be our taillight signal. And the brown wire. That's going to be our stop and turn. So, what we need to do, Cut those. About like that. In each end, we're going to strip back an insulation and crimp on a blue terminal. We're going to do that for our three remaining ends there. So with all those crimped on, you can take your diodes and the side here closest to the connector plug. I'm gonna put on the outside of the diode. Let me just turn and go color for color. So, brown to brown, Black with the white stripe to the other end, I think you can take our new wires and hook them, hook them on up. So, since the black wire with the white stripes is our taillight signal, we want to hook the brown and white wire to it. And since the factory brown is going to be her stop and turn, we want to take the yellow wire and hook it to it. So I went ahead and just stuck our diodes together there, using the sticky tape, that's on the back of them. And now we can go ahead and plug this in. Line it back up. And simply just reinstall it perhaps you would. Mechanic So now over here on the passenger side, I essentially did the same exact thing. Even the wire colors are the same. Black with the white stripe is your taillight. So you're going to hook your white wire up to that diode. The brown wire, it's going to be your stop and turn. And so you're going to hook your green wire up to that diode. So that's how it turned out. Again, I'll just do what we did on the other side, stick them two together. Get it plugged in, And re-installed. Mechanic That's a good idea to test your wiring and make sure it's working properly. So I hooked up to a test box. You can hook up to your motor home, but keep in mind if your motor home has an issue, with its wiring, it's going to translate to the back of our receiver here. But, that side will turn on her taillights. We'll hit our left turn signal, Our right turn signal. And our brakes. Ryan And that'll finish up our look at and our installation of the Roadmaster diode wiring kit on our 2017 Subaru Crosstrek..


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