Roadmaster Universal Diode Wiring Kit Installation - 2021 Jeep Wrangler Unlimited
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How to Install the Roadmaster Universal Diode Wiring Kit on a 2021 Jeep Wrangler Unlimited
Hey everybody, Ryan here at etrailer. Today, on our 2021 Jeep Wrangler Unlimited, we're gonna be showing you how to install the Roadmaster diode wiring kit. But before we do that, why don't we check it out and make sure that this is right for you. So, before we actually start to check out our diode wiring kit, I figured it'd be useful just to kind of touch base and refresh yourselves on the main components that we're gonna need to flat tow our Jeep down the road in the first place. There's going to be a total of five main components that you're going to need. The first one is gonna be the base plate.
And what that's gonna do is provide us with a solid and reliable connection point. That way, we can hook our tow bar up to it. The tow bar is gonna be the second component. And this is more or less gonna be the physical link that connects the front of your Jeep to the back of your motorhome. The third main component is going to be safety cables.
And these are there in the event of an unlikely disconnect. These are gonna keep your Jeep paired up with your RV. The fourth main component is going to be tow bar wiring. And what this is gonna do is transfer the lighting signals from the back of your coach to the back of your Wrangler. That way, people around you will know what's going on and you'll be safe and legal.
And last but not least, the fifth main component is going to be a braking system. And what this is gonna do is apply the brakes in your Jeep, whenever you hit the brakes in your motorhome, helping to give you a more predictable and safe stop. And with all that said, this is gonna be a great example here of how the diode wiring is going to work. So, in our motorhome, whenever we're flat towing, the Jeep behind it, say, if we hit our left turn signal, we have it going on our motorhome as well as back here on our Jeep. And that holds true for the right turn signal, the taillights and the brake lights as well.
So, whenever you're flat towing, people are gonna know what your intentions are whenever you're going down the road and be able to plan for that. With that said, when it comes to tow bar wiring, you do have a few choices. And honestly, the diode wiring is probably my top pick. And I say that because once you have it installed, you're not even gonna be able to know it's there. It looks pretty much 100% factory. And just as important, it's super easy to use. Whenever you're getting ready to flat tow, all you're gonna have to do is plug the cable in from the back of your motorhome to the front of your Jeep, so it's really simple. And compared to some of the other kits available out there, like, let's say, magnetic lighting, for example, that's the one I'm sure a lot of people have seen it where you have lights kinda stuck up here to the top of your Jeep, or the sides, you know, wherever there's metal. A lot of these Jeeps now, they're fiberglass, so you might even have a problem trying to use them. But even ones that are similar to that, the problem is you have to set them up every single time, run wires all the way up to your motorhome. Do the same thing when you're done, you know, take it all back off and everything else. And then when you're over the road, you know, what's really important, storage. You know, you don't have a ton of spots to keep things. And that type of magnetic wiring, it's a big bundle of wiring and some lights, so you're gonna have to find a place to keep it too. So, with diodes, that's just something you're not gonna have to worry about. And once you're in, they're in, and you're ready to use them. Whenever you are ready to hook up, like I said, all you're gonna have to do is plug in. So, you'll take one end of your cable, plug it into the front of your Jeep. And the other end of that cable is gonna get plugged in to your motorhome. With that said, there is several different kits available. And which one is going to be best for you is pretty easy to figure out. So, in this case here today, we're showing off the kit that has the coiled cable. And you would use this kit if you we're planning on using a tow bar, like this one here, one that does not have any channels in the bottom of it. With the coils, you know, it's gonna keep it high and tight off the ground, but still stretch out and give you that extra length whenever you're going around turns and things like that. Another kit that is available has a straight cable. And it's gonna look like this. And you're gonna use this kit if your tow bar has those channels in it, so that on the side here, you'll have those channels. That way, you can run your wiring through it and use the tow bar like it's intended to be used. With that said, too, there's also a hybrid kit, which essentially is a straight cable, like this, and then here at the end, maybe the last foot or so, is coiled. And you would use that one, again, if your tow bar has channels. And with that one, the hybrid one, it's a little bit longer than the other kits. So, let's say, if you had a really long tow bar or maybe you had a really long high-low adapter here that you had used, so you have quite a bit of space, that might be a kit worth looking into. And then there's a few more. There's a kit that has a seven-way round for your motorhome and a four-way round for the Jeep side. Little less common, I feel like if you're gonna go through everything to wire it up, you might as well get the six-way round. That way, if you ever wanna add things in the future, you have it, but this is an option for you. There's also a kit that uses a four-way flat to four-way flat. So, you know, pretty uncommon. You don't see a lot of that here. But if that's what your motorhome has and that's what you wanna use, that's perfectly fine, it's another option. And then last but not least, I do wanna mention, there's a kit that comes with the wiring and the diodes, but no cable at all. And they make that kit because some of the higher-end tow bars actually come included with the cable as well as the connector plug. And so, if you end up picking up that type of tow bar that comes with those components, you're just gonna need the kit that kinda has the bare bones. That way, you're not buying stuff that you already have and you really don't need, so really, you know, it's nice to have those options. I know that was a lot, but it's pretty easy to figure out what kit is going to be best for you and be the most ideal thing to use. But other than that, at the end of the day, a kit you really can't go wrong with. I definitely wouldn't hesitate to use it myself. We do a ton of these here at etrailer and rarely run into any issue, so I can say with some confidence that they're pretty reliable and, you know, they get the job done. Now, as far as the installation goes, I'm not gonna lie, it's not terrible, but it's not super easy either. You do you have to route some wires back and that takes up some time. And you do have to tap into your factory harness. But on the Jeep's, everything's pretty open, pretty easy to see and get to, so if you wanna follow along, I can show you how I did it, and hopefully it won't give you too many issues. But speaking of that, why don't we go ahead, pull them to the garage and hook it up together now. To begin our install, we're gonna be here at the front of our Jeep. And what we're gonna do is mount up our connector plug here and get it all hooked up. So, I took one end of the bundle of wire, kinda just brought it to the front here where we're gonna be working. You're gonna take the rubber dust boot off of the connector plug and slide that over your wire. And then we're going to separate each individual wires, so we'll carefully cut in between them. Kinda pull them apart a few inches. And what I like to do is kinda cut a little bit of the end off to just kinda give us a fresh start here, like so. And we're gonna strip back the ends of the insulation, about that far. And once you have it stripped, go ahead and give the wires a good twist just to keep them nice and tight. Now, we can grab our connector plug and prepare this. So, we're gonna be using four out of the six available terminals. And the way these are gonna work is these are gonna be set screws, so you can take a Phillips and just kinda back that screw out. But try not to take it all the way out, 'cause if it comes out, you usually drop it and then it's a pain to find. But it might be a little tricky to see here, but there is gonna be labels indicating you what wire goes where. This one here, it's labeled TM for taillights, so the brown wire will go to it. And this one here is GD for ground, so the white wire will go there. And this one is LT for left turn, so the yellow wire will go to it. And then RT for right turn, so the green wire will go there. So, you're just gonna take the appropriate color wire and push it down. These terminals are kinda shallow, so I think what I'm gonna do is shorten up that wire. We really don't need all that extra bare wire hanging out, so I'm gonna kinda cut these in half probably, and that should do the trick. So, we'll go ahead and get that plugged in. That's about how you want it. You know, about the wire insulation to be flush with the top of that. So, I will hold that in place and tighten down that set screw. I'm gonna go ahead and do the same thing for our remaining wires here. So, here's what the wires look like once they are hooked up. And for now, I'm just gonna put the cover over it. What you can do is apply dielectric grease and sealer to these terminals to help protect them against corrosion. What I like to do is wait till I have everything installed, that way, if I have an issue, I don't have to deal with, you know, all the stuff and grease and everything in the plug, so we'll wait to do that till our flat tow is set up. But for now, we'll just put the cover over it. Take our connector plug and secure it to the base plate. So, I have two small screws. I'm gonna run and grab some and get this secured. With the appropriate screws, go ahead and get this ran down. And now, what we can do is route the rest of our wiring towards the back of the vehicle. So, I'll go ahead and do that now and show you the path that I took to get there. So, I went ahead and got our wiring routed. So, here's where it comes out at the back of our six-way connector, it kinda just comes along through here. There's a lot going on here, so do your best to avoid any hot or moving parts, but we just shot this, choo, right over to here. And then right here in this area, there's already a factory hole in the frame, so I just pushed a grommet or a bushing into it. Took our wire, pushed it through there and continued to push it through our frame rail. So, that wire kinda, it's fed along through here. And this can be kind of tricky, so take your time with it, you know. Sometimes, you go from the opening in the frame and kinda pull it all through and whatnot. But this is going to continue on along our frame up until about this point. And if you come and look on the outside of our frame rail, we'll be able to see where it comes out and kinda goes up and over our fuel tank. So, it is somewhat tricky to see, but this hole here in our frame, it's about even with our back and front door, kinda where it meets, if you just we're to draw a line straight down. Right in here, the wiring comes through here and then there's a hole on the inside of the frame that I've pushed it through. And that wires have to come up on top of our fuel tank and kinda get routed diagonally towards the back of our Jeep. So, that wire is going to come right up through here. And I continued to push it towards the back of our vehicle over this rear subframe. And right here, our wires are gonna drop down. But at this point, we can go ahead and focus on our white wire. This is gonna need to get grounded, so we'll go ahead and do that now. So, once I get to this point, I saw these factory studs here, and figured this would be a great place to ground our white wire. And so, what I've done is separated the white wire from the rest of her harness, kinda how we did at the very front there, kinda carefully cut in between the wire and separated it. I brought it back here to the appropriate length and trimmed off the rest of the white wire that we don't need. Right this minute, you do wanna hold onto it 'cause we'll probably use it in a little bit, but we're gonna strip the insulation back on the end. And what we're gonna do is take a ring terminal. Slide that ring terminal over the bare end of the wire and crimp it down. And now, that's ready to get hooked up. So, we'll come back with a 10-millimeter wrench here and get one of these nuts removed. It don't really matter which one we decided to go with. We'll pull that off. Put that ring terminal over the stud. And just simply tighten that back down. After the ground, I continue to route our wiring. So, I just brought it along through here, kinda up and over and this is where it comes down. Now, at this point, we can pull the green wire off of the yellow and brown. The green wire is gonna go up and over the frame and come down here. And if you remember, that extra piece of white wire that we had trimmed from the ground, what I did is actually just taped one end of it to our green wire. And this is gonna get pulled up into the taillight pocket in a moment. So, with that said, that white wire, here's where it comes back over the frame. And this is gonna get routed now along with our yellow and brown wire. So, I just ran it along through here, up and over the frame as well, and this is where it drops down. So, with that said, now we can go up and get our taillights removed, so that way, we can pull our wires up into the pockets and get them hooked up. So, now at the back of our Jeep here, we need to get the taillights removed, so I open up our hatch and our glass and everything. And if we look right inside of our Jeep here, we're gonna have this cover. And you can take a flathead screwdriver and just pop that up. Then underneath it, we're gonna have a plastic fastener. And I'm gonna take a 10-millimeter and get that removed. And we'll pull it out. And that's all that's holding the taillight in. Here's that fastener, so I used a 10 millimeter. It looks like you could also use what looks like a Torx bit as well, so either or should do the trick. But with this out, now we can get our light removed. We can grab our taillight. And you can kinda just pull that out and we can get it disconnected. Now, in our case, we already have some existing trailer wiring hooked up, that's what this T-connector is. Usually, you would just have one wire, you know, kinda this end plugged into the taillight, but the same concept. We're gonna disconnect everything. Pull back on the red tabs, push down on the clip. And with our light off, we can now set it to the side. We'll repeat the same process to get the other one out. So, now what I've done is reached down into our taillight pocket and grabbed our wires that we left below. I pulled them up and I cut some of the, you know, the extra off. You don't need another five-foot of wire hanging back here, so trim that off. I stripped all the ends back of the insulation. The yellow wire, I crimped on a blue terminal. The white and brown wire, we're gonna do something a little different. You're gonna take them and twist the ends together nice and tight. Then you're gonna use the yellow terminal here, so that's gonna slide over both ends and get crimped down. What I went ahead and done was remove the tape. There's some tape that goes over your factory wiring here. I pulled that off and tested the wires for their functions. And what we we're looking for is our brake light signal and our taillight signal. And what I found was this white wire here with the gray stripe, that's gonna be our taillight signal. And this yellow wire here, that's going to be for our stop and turn. So, about halfway up, I'm gonna cut them. And you're gonna strip back the ends of the insulation on all four ends there. Give the wires a twist. And all of those ends are going to receive one of these blue terminals here. We'll get this crimped on and do the same thing for those remaining ends. Now, we can get our diodes hooked up. So, what I like to do is peel this backing paper off and stick them together first. And then this is going to get plugged into all of our ends here. So, the ends closest to the connector plug, that's gonna go on the side of the diode that says out, and it's gonna have that single terminal. And then we'll just go color for color. So, the white and gray will get plugged into the white and gray diode. The same thing with the yellow. And now, we can hook up our new wiring. So, since the white and gray is gonna be our taillight signal, we're gonna take our brown and white wire, and plug that into that diode. And since the yellow is gonna get, gonna be our stop and turn, we're gonna plug it into that diode there. With these all connected, I kinda retaped up some of our wires. You know, I zip tied them to keep everything secure. And with that done, we'll go ahead and get everything plugged back on in. And with all plugged in, go ahead and reinstall our taillight the opposite way that we removed it. Over here on the passenger side, essentially, we did the same exact thing. Pull the wires up into the taillight pocket and get them hooked up. Really, the only difference is gonna be the color of the factory wires that we're gonna tap into. So, in our case, this green wire here, the factory one, that's gonna be our stop and turn circuit. And the white wire with the orange stripe, that's going to be your taillight circuit. So, with that said, the green wire from our new wiring kit, that gets plugged into the diode with that factory green wire. And the white wire with the orange stripe, that diode. Our new white wire is gonna get plugged into there since this is the taillight circuit. So, that's how it turned out. And with this one done, we'll go ahead and just get it plugged in just like the other side. It is a good idea to test your wiring to make sure everything is working properly, so I just hooked up to your test box. You can also use your motorhome. But keep in mind, if your motorhome has some issues of its own, you may get some inaccurate readings. With that said, we'll try out our taillights, our left turn, our right turn and our brake lights. And that'll finish up our look at and our installation of the Roadmaster diode wiring kit on our 2021 Jeep Wrangler Unlimited..
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