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Roadmaster Battery Charge Line Kit Installation - 2021 GMC Sierra 2500

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How to Install the Roadmaster Battery Charge Line Kit on a 2021 GMC Sierra 2500


Hey everybody. Ryan here at etrailer. Today, on our 2021 GMC Sierra 2500, we're gonna be showing you how to install the Roadmaster battery charge line kit for towed vehicles. But before we do that, why don't you check it out and make sure that this is gonna work for you. So, whenever somebody is flat towing their vehicle, a battery charge line kit is something that I almost always recommend. And I say that because whenever you're towing your vehicle down the road, the majority of the braking systems, the supplemental braking systems, are gonna run right off your vehicle's battery power.

And that's fine, that's how it's designed to work. But one of the things that can happen is if you start to tow for quite some time and, you know, you don't want to start your vehicle off every now and again, and things like that, what can happen is that breaking system can slowly diminish your battery. It uses a little power, and a little power, and a little power, and over time, it can drain your battery. And that can cause a couple of things. I'm sure pretty much everyone has experienced a dead battery.

It's not fun, vehicle won't start. And not to mention, it kind of, it kind of hurts the life expectancy of the battery too. If you run a battery all the way down, it might take a charge again but it's going to kind of go through one of those cycles where it can shorten life expectancy. So, a charge line is going to really combat all those issues. And what it's gonna do is essentially, more or less trickle charge your battery whenever you're towing it down the road.

So, how it's gonna work is whenever you're hooked up to your motorhome, the 12 volt auxiliary power coming from your motorhome is gonna run up through here, through the circuit breaker, and into the positive battery terminal. And so, everything's gonna be protected with the circuit breaker. If a short or something like that would happen, this would trip. And also, it's not gonna affect your motorhome's batteries or anything like that. Since it's using the exalt, auxiliary power from the seven-way in the motorhome, it's not gonna drain those batteries because your motorhome has its own charging system and everything else like that.

So, this is a great way to make sure that your battery stays topped off whenever you're towing it down the road. One thing that I do wanna address is a lot of people ask, "I have this braking system or that breaking system." That's not the same brand as our Roadmaster charge line. They're wondering if that charge line is gonna work, and the answer is yes. Charge line really don't care. It has one job to do, send power from the back of your motorhome into the battery. But other than that, this is a great way to kind of help build your confidence whenever you're towing, knowing that your truck's battery is in tip-top shape, and truck's gonna start whenever you get to your destination. Now, as far as the installation goes, really straightforward. Essentially, hook up or bolt down our breaker, we run a couple of wires. So, really shouldn't give you too many issues or take up a bunch of your time. So, why don't we go ahead and knock that out all together now. To begin our installation, we're gonna be here underneath the hood of our truck. And in our case, we're gonna be working on the driver's side. First thing that we need to do is mount up our circuit breaker. So, here's our breaker. I just secured it down to this part of the frame rail here, just using the provided self-tapping screws, so pretty straightforward. When you mount this, make sure it's gonna clear your hood and everything like that. And generally speaking, you wanna get this close to the battery. In our case, since we have a diesel, we have two batteries. But since our braking system and everything runs or is connected to this one, I opted to put it, our charge line, connected to, to this side. But with that said, what we need to do now is run this wire down to our six-way. So, I already done that. I'll show you how to crimp these on in a minute and everything. But what you're gonna do is crimp on a small ring terminal to one end of your wire, the full length of it. Don't cut it yet. Put it on this brass colored post that's labeled battery, but this one is gonna go to the front of our car. So, that's because essentially, the motorhome is acting as your battery. But tighten this nut down, and then this wire is simply just gonna drop straight down through this opening, and it's gonna come out on the underside of our truck, more or less. So, our wire dropped down through here and I just ran it over to our existing six-way. So, in this case, this post here in the middle, we're gonna connect it to that. So, back our set screw out, so I can get to it here. And you're gonna strip this wire back a little bit. Push that one in. Simply tighten our set screw back down. Once this is tight, you can go ahead and reassemble it. Mount it back up to your, your base plate or, or your bracket. So, back up top now. We didn't use that whole length of wire that we ran down to our six-way. So, there's about a foot or so left of it. And what you wanna do on one end of it, crimp on a small ring terminal, connect it to the silver post on your breaker. And the other end is actually gonna go to the battery. But first, we have to get it set up. So, I do all the terminals. Strip it back and give it a good twist. This one, we're gonna take the larger one. Just slides on, and you crimp it down. So, that's all there is work. But once that's done, if you take off, if take off your lid here, this wire is gonna get routed to this post. So, what I've done is just used a pair of snips, cut out a little square there. Same thing in the lid. That way, it doesn't pinch the wire when we close it. Gonna get that ready. Gonna take this nut off using a 10 millimeter. Slide our ring terminal on it, and then simply just tighten it up back down. So, from there, I went ahead, put our cover back on. And then I took some of the included wire loom and just covered up our wires to help clean up our install look. And that'll finish up our look at and our installation of the Roadmaster battery charge line kit on our 2021 GMC Sierra 2500..


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