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Roadmaster Tow Bar Wiring Kit Installation - 2021 Ram 1500

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How to Install the Roadmaster Tow Bar Wiring Kit on a 2021 Ram 1500

Hey everyone, how's it going Today, we're gonna be going over and showing you how to install the Roadmaster diode wiring kit here on our 2021 Ram 1500. It's just gonna be one of the several things that we're gonna need to successfully flat tow our Ram here. So, in addition to that, we're gonna need our tow bar. We're going to need a supplemental breaking system, that's required in most states. We're also gonna need safety cables. And then last but not least, we need some sort of lighting system.

So, a diode wiring kit is gonna transfer the signals from the motorhome to our towed vehicle here. And the reason that's important is, while we're driving out on the road and we're flat towing our vehicle here, we can't always see the lights on our motorhome. Therefore, we need a way to signal other motorists on the road, the signals that we're gonna be making, so we can arrive to our destination safe and sound. So, there's actually a couple different kinds of wiring kits you can use. We have the diode kit, which is what we have installed here.

There's magnetic lights and there's also bulb and socket kits. Now, if you ask me, the diodes are really the best because they're the most seamless. They actually use the factory tail lamps there. The stop and turn signal and the running light circuits are all gonna come through your factory taillight, so they're really the most ideal. They do require splicing, however, but it's only a couple of wires, so really not a big deal.

The bulb and socket kits, they don't require splicing, but you have to drill into your taillights there and there's not a lot of room for air with that. And then the magnetic taillights, you kinda have to deal with those unsightly bases on your roof there. You can risk scratching the paint, and you also have to run a wire down the hood. So, overall, the diodes are the best if you're gonna be consistently flat towing your vehicle. So, although you do have to splice into the vehicle's wiring, the diodes that we've been referring to thus far, what those actually do is they stop the backfeed of electricity.

Therefore, we don't have to worry about any issues with the lights on our motorhome affecting the lights on our vehicle and vice versa. Everything is gonna be protected from one another, so you don't have to worry about any pesky lighting issues. So, a Roadmaster diode wiring kit comes in a few different configurations. Now, those configurations, the variances, are gonna be what umbilical cord it comes with, or if it comes with any at all. There is a version of this kit that'll allow you to use an umbilical cord. Some tow bars actually come with their own, such as the Roadmaster Nighthawk. So, in which case, you wouldn't need an extra one, and you would just purchase the diode-only kit. But if you don't have that tow bar, you don't have an umbilical already, you will need one, and that's where the different options come into play. Now, there's actually three different umbilical options. And the right one for you is gonna come down to what tow bar you are using. So, over here, we have a coiled umbilical cord. This is fully coiled. And this is gonna be designed for tow bars that don't have the integrated channels on the bottom. If you don't have any integrated channels to run your safety cables and your wiring through, then you're gonna wanna consider the fully coiled umbilical cord. This is gonna ensure that the wire doesn't drag on the ground. In the center here, we have the hybrid. And then to the left of that, we have the straight. Now, these two particular ones are designed for tow bars that have that integrated channel in the bottom that we just talked about. The main difference is the hybrid is gonna provide more protection than the straight, because we still have sort of that hybrid design where we have the coiled at the motorhome side between the motorhome and the tow bar. Whereas a lot of the times, you actually have some slack there with the straight cable, so both of them will still go through the channels, but the coiled hybrid one is a little bit better. However, they're all, three, are gonna work for you. You just need to make sure you'd pick the right one, depending on your tow bar. So, if you go with the kit that has the umbilical cord with it, you're also gonna get this six-way trailer plug. So, our umbilical cord is actually a seven to six-way. Therefore, it's gonna plug into the seven-way on your motorhome, and then the six-way which will install on the vehicle. Now, what I like about this is, although, most of our applications are only gonna require the four-way, the seven to six-way allows us to route a battery charge line from the motorhome to the vehicle there. That way, we can as the vehicle's battery while it's in tow. So, in regards to installation, as we said, we do have to splice into a couple of wires, but really don't let that guys, don't let that scare you. It's really not a big deal. We're not gonna damage the vehicle in any way. The bulk of the installation is gonna be routing our wiring harness from the front of the vehicle to the rear of the vehicle. But aside from that, everything's pretty straightforward and we can actually walk you through this entire process step by step now. Make sure you give yourself, guys, a couple hours to get this done. So, the first thing we're gonna do to start our installation, we're gonna take our bonded four-pole wiring harness, which is this here. And we're gonna find the spot on the front of the vehicle where we're gonna be installing the trailer connector. Now, for this particular vehicle here, most of the base plate installations have integrated trailer connector mounting brackets. Ours is gonna be over here on the driver's side. You can see these two little standoff pegs here. So, these are welded to the base plate, and these are designed to mount our trailer connector. So, yours may be a little bit different, depending on what base plate kit you have. But with that being said, we're gonna come up, I'm gonna reach out back, behind the bumper there, and I'm gonna feed the wire through the tow hook opening. And then I'm just gonna secure it here and give ourselves a little bit extra to work with. Probably, I'll secure it around the safety chain tab. Like we said, we wanna make sure we have plenty to work with here. And then I'm gonna begin running the wire from this point here, all the way back to the rear of the vehicle. And now that we have our excess secured outside of the vehicle here, now we're gonna jump underneath there and begin running the wire underneath, all the way to our taillights. So, we've got our wire in now, so we'll go ahead and show you how we routed it to the rear. Now, for starters, we actually made a loop into our engine bay here, and that's because our specific supplemental breaking system we're using actually ties into this. So, if you have one that does tie into the diode wiring, you just make sure to make note of that and give yourself some extra wire. But if not, you could obviously just proceed going to the rear here. This is where the end of our loop comes down. Now, we did use some of the wire loom that comes in your kit, and just these first couple feet of the wire here just to make it look a little better. But now, we're gonna go up and over, you can kinda see the colors of our wires here. So, we're gonna go up and over this crossmember, and it's actually gonna come out here. So, we need to be very careful when we're working in this area here because we have our steering box and we have the front axle there. So, any moving suspension components or steering components, we wanna make sure we avoid, 'cause we obviously don't want the wire tangled up in those. But now, we're gonna go up and over. And throughout, we're gonna have zip ties. You should be able to see these. I left all the ends on there just to give you guys a little bit better view, but you wanna make sure you use plenty of zip ties there just to keep the wire from falling down, so it stays in place. And we're gonna jump all the way over here, back, behind our front axle. And if we look up in this area, you should see our wire coming out. The starter is actually right over there, just for a frame of reference. And we actually came up and over this way. And at this point here, I snake the wire into the frame, because we have this very large resonator here, or this is actually the catalytic converter and these get very hot, so we wanna make sure that wire stays as far away from it as possible. So, from here on, all the way back, we have it snaked through the frame, all the way in here. And this is where we're actually gonna come out of the frame here. There's a nice large hole there. Now, if you're wondering how we got the wire into the frame and out on this point, we actually just used a piece of airline tubing. We snuck one in, all the way through here, pulled it out this hole. And then we tied our wire to the other end and just pulled it the rest of the way through. Pretty simple process. But now, we're gonna be tying it to the brake lines. You can see, we have some more zip ties. We're just gonna be tying it to these existing lines here. These are already secure to the frame, so we don't have to worry about them moving. So now, we're gonna come between the frame and the gas tank. It's gonna be a little hard to see our wire, but it is up there and we're just, again, zip tying it to those existing brake lines. They're gonna come all the way here, again, another zip tie. Come all the way here. And then once we get past the gas tank, if we look up in this little pocket there, you should see our wire. And again, they're up a little bit higher now, but we're just, again, securing it to those same brake lines. Then we're gonna go up and over the jounce spring, and this is gonna be up and over the rear crossmember. And then we actually switched around to the outside of the frame, and we'll jump around to the back there and we'll show you how we routed that there. So, we're on the outside of the frame now. And as we said, we just kinda came up and over the frame there, we have a large wiring harness we secured it to. And then it's coming back here. So, keep in mind, if you made a loop in your wiring harness earlier, you're probably gonna run out of wire around this point. Therefore, you will need to extend it. But if you didn't make that loop, chances are, you can still reach the rear. And here you can see, we have the rest of our slack. We're gonna leave this here for now. I'm gonna go back and remove all of those zip tie ends and then we're gonna remove the taillight, so we can make our connections. So, in order to do this, we're gonna take a T25 Torx bit. We're gonna have two screws on the inside there. We'll remove those both. And then what we're gonna do is we're gonna take a flathead screwdriver. And we have these little push fasteners here at the top and bottom. And you're just gonna pry up that center section there, and the rest of it should come out as well. Just like that. And we have one at the top here. In order to get this one at the top, we actually have to lift the tailgate up a little bit. That way, we can move that cable out of the way. But this one will come out the same way as well. And once we get that one out, we're ready to pull the taillight assembly out and away from the vehicle. So, we're just gonna grab in there as best as we can. So, we're gonna pull out to release those clips. So, at the top here, we're gonna have a connector that we need to remove in order to get the taillight assembly off. So, there's gonna be a red locking tab that's gonna stop us from depressing that tab there, so we do have to put that locking tab back. And then we should be able to squeeze that connector and then pull out. Some of these can be pretty tight. So, what I recommend doing is, I'm just taking our screwdriver here, so we can depress that clip. And then we can pry it out there at the bottom. Just like that. Now, we'll go ahead and set this aside. So, what we're gonna do next is you're gonna have all kinds of fabric tape covering our wiring. So, we actually need to splice into these wires. So, what we're gonna do now is we're just gonna take some time and we're just gonna remove the fabric tape here. You wanna be careful not to pierce any of the wires. And also, I'd like to point out, this little red wire here, this customer has something spliced in behind here already, so just disregard this. But with that being said, we're gonna go ahead and take a knife now and just take our time to remove all of that fabric tape there, so we can expose the wires. So, as you can see here, we got quite a bit of that fabric tape pulled back. I actually went ahead and undid one of those connectors, too, that was holding your wire to the body, just to give ourselves more room to work. So now, the two wires we're gonna be interested in are pin one and two, these two wires here. So, we're gonna have a white wire with an orange stripe. That's gonna be for our running light circuit. And then we're gonna have a white wire with a green stripe, directly next to it, and that's gonna be for our stop and turn signal circuit. So, we have identified both of those wires. What we're gonna do now is we're gonna take that wiring that we showed you running underneath the vehicle earlier. Actually, I was just able to reach down in there and pull that the rest of the way through, it's just a fairly short distance. So, you wanna go ahead and get this behind the taillight pocket here. And then what I'm gonna do is I'm gonna begin splitting each of these ends back, separating the wire from the harness there. And then we can go ahead and start making our connections to the diodes. So, now that we have all of our wires separated, we're ready to start making our connections. So, the first thing we're gonna do is we're gonna be grabbing this white wire with a green stripe. And about halfway down, I'm gonna go ahead and cut that in two. And once we do that, we're gonna strip off some of the jacket on either side of that wire. Just like that. And then we're actually gonna be crimping on the blue spade terminals that come preattached to the diodes. So, we'll just take one here. I always like to twist the wire strands there, just to make sure they don't fray. And just stick that through, crimp it on. Give it a wiggle, make sure it's on there nice and good. Go ahead and do that for this other wire as well. So, once we get a terminal on both sides of this wire, what we're gonna do is we're gonna grab the wire out of the harness that we're gonna be using for this side. So, that's gonna be the yellow wire here. So, I've got plenty of extra. I'm gonna go ahead, just give ourselves more than I think we're gonna need, but not too much where it's a pain to work with. Let's just go ahead and cut the rest of that off. And then on this wire here, we're going to attach to one of the final diodes. Just like that. Now, we'll go ahead and hook up our diode to all of these spades. So, the outside is gonna be going towards the connector, so this one here. And in regards to the inside, we can do either one, it doesn't matter. One can be our yellow wire, one can be the white/green. But there we go. That's gonna be it for this circuit here. Now, the next thing we're gonna do is repeat those same steps here for this white and orange wire using the brown wire that comes from our harness. But before we connect our final wire there to the brown wire, to one of these, we're actually gonna be making a jumper wire that goes from this side to the other. So, we're gonna go ahead and fast forward through all of those steps until we get to there, so we can show you that. So, as you can see now, we already have our other diode in place. And I just simply cut that white and orange wire, which is for the running light circuit. The one that goes to the connector, goes to the outside. The other one going back into the vehicle, goes to the inside. So now, we're gonna take our brown wire here. We're gonna go ahead and cut off some of that excess, just like we did with the yellow wire. I'm just gonna kinda match the link that we took off. So now, what we're gonna do is we're gonna strip back the jacket on this end of the wire. And before we attach that to a spade terminal and attach it to our diode, as we said there, we need to make a jumper harness to go to the other side. So, what you can do is you can take this wire that we just cut off, the brown wire that we just cut off, and we're gonna use this to tie into this wire here and then run it to the other side. Now, you may or may not have enough of this wire left over. For our particular application, we didn't, just a base on how we ran the wire. So, in this case, we actually need to grab a longer wire or you can extend the wire that you have. It doesn't make any difference. But we do need to make sure we have enough wire to get to the other side. So, I'm gonna go ahead, I'm gonna connect these two wires here. And then instead of the blue spade terminals, we're gonna have a yellow one. And once I get that crimped on there, I'm gonna attach that to the other side of our diode. Just like that. And what I'm gonna do next is I'm gonna peel back the backing tape there on the diodes, and I'm just gonna stick them together. And if I can, I'm gonna try to zip tie them to a harness in there, so they're not banging around as much. But whatever we can do just to sorta secure them an extra step. That's pretty much gonna finish up the diodes here over on the driver's side. So now, the next thing we're gonna do is we're gonna take this white wire here. So, I'm gonna route this around and pull it out this way. So, this is gonna be for our ground. In your kit, you're gonna get a ring terminal along with a self-tapping screw that we can use to secure this wire. So again, I'm gonna cut off some excess 'cause we don't need this much. And then I'm going to strip some of the jacket off, so I can attach that ring terminal that we told you about. So, it looks like, and then we'll take the self-tapping screw that comes in your kit, it looks like this. And we'll attach this to a bare metal part here in the taillight pocket. Just make sure, wherever you do attach it, it doesn't interfere with the reinstallation of our taillight. So, now that we have our ring terminal crimped on, we need to find a bare metal spot inside the taillight pocket here to attach it using the self-tapping screw. So, you gotta be careful when you're drilling into this back panel here, 'cause if we feel along the backside edge, some of it is double walled. But there is a section there where it's only single walled, so that's gonna be the easiest to drill into. But just predrill your hole with the step or the self-tapping bit there and then we can come back to secure the ring terminal. So now, all that's left to do is to take our two remaining wires. We have our brown jumper wire and our green wire. We're gonna route those down, back underneath the vehicle, over to the passenger's side, and then we'll show you the connections once we get over there. So, here you can see, we have our brown and green wires that we routed over here. Now, basically, it was pretty simple to get it over here. We just ran it between the trailer hitch and the spare tire and just zip tied it to some existing wiring. It's pretty much a straight shot over here. There really isn't too many obstacles. I did go up and over the frame, but with that being said, pretty easy. Now, we have both the green and brown wires here into the passenger's side taillight pocket. So, basically, we're just gonna be doing the same thing we showed you on the other side, for the exception of we're not gonna have a jumper wire going into our running light wire. That's just gonna go straight into the diodes, but our wire colors are gonna be the same. The white and orange wire here in pin one is gonna be for the running lights. And then the white and green wire in pin two is gonna be for our stoplights. So again, just clip both of those wires and we can strip back some of the jacket, so we can attach our diodes. So now, all that's left to do is to simply resecure our taillight here. Tuck our diodes away, and then insert our fasteners. So now, what we're gonna do is, once we got the taillights resecured and all of our diodes are in place, we're gonna come back to the front of the vehicle here, where we started at, we're gonna take this extra wiring and we're gonna be attaching our trailer connector here that looks like this. So, what we're gonna do now is I'm gonna go ahead and start splitting these wires, just separating them from the harness. And once I've got them all separated here, I'm gonna take the boot that comes on the back of the trailer connector. So, your kit may or may not come with this trailer connector here. So, if not, if you just get the basic version, there's a couple different styles that we explained earlier. So, if not, you'll just need to get your trailer connector and put it on there. But now, we have plenty of extra here, so I'm gonna go ahead and cut some of this off. And then I'm gonna begin stripping back the jacket on each of these four wires here. We don't need to strip back a ton. So, now that we have each of our wires stripped, we're gonna take our trailer connector here. And on the back of your trailer connector, again, depending on if you have the kit that has it or not, but it should be labeled for our individual circuits. RT, for example, that's gonna be for right turn. We're gonna go ahead and loosen the screw of that terminal, and then we're gonna stick our green wire in there. And we're just gonna repeat the same process for our other circuits there. They should all be labeled. The next one we'll do is ground, so GD. And then left turn will be LT. That'll be your yellow wire. And then taillight or the running light wire is usually labeled TM. Yep, that's TM there. So, that'll be the brown wire. And then before I seal up all of these connections, we're actually gonna test it out to make sure it's working. And then once we verified this, that's when I'll come back with our silicone here and cover up all of these circuits, so I don't ever have to worry about water getting in there. So now, we actually have a tester box that we can use to test out the taillights. You guys could obviously just hook up to your motorhome as well, though. But nonetheless, we'll go ahead and show you, we should have the taillights. And we're gonna have the left turn, followed by the brake lights, and then the right turn. So, now that we've verified that all of the circuits are working correctly, we can go ahead and seal up all of these contact points in here. This being on the front of the vehicle, a lot of the times, when you're driving and it's raining, water can get in there. And if water gets in between those contacts, it's gonna corrode it, and that's gonna give you lighting issues. So, not something we want. So, in order to prevent that, we're gonna take some silicone here. We're just gonna fill it in between all of those little slots and crevices as best as we can. And then once we do get them all filled up, that looks pretty good, we're gonna take our boot here, and we're gonna slide that over the back of the connector, and then we're ready to mount the connector to the two tabs on our base plate. Now, that could vary little bit, depending on which base plate kit you have. Our particular one is a Roadmaster, so it has these two little standoff tabs here that are designed to attach the trailer connector. But if yours doesn't, you're gonna have to find a different way to mount it. And there we have it. And that's gonna do it today for our look and installation of the Roadmaster diode wiring kit here on our 2021 Ram 1500..

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