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Roadmaster Automatic Battery Disconnect Installation - 2015 Smart fortwo

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How to Install the Roadmaster Automatic Battery Disconnect on a 2015 Smart fortwo


Speaker 1: Today, on our 2015 Smart Fortwo, we're going to be taking a look at and explaining how to install the Roadmaster Automatic Battery Disconnect with switch for towed vehicles with supplemental braking systems, part number RM-766.This is what our Battery Disconnect looks like when it's installed. What this is going to allow you to do, this is going to allow you to separate the power from your battery. What I mean by that is in some vehicles, when they're being flat towed, the key has to be in the on position to put it in tow mode. The key has to remain in the on position. Once the key is in the on position, all of your accessories stay on inside the vehicle.What this is going to allow you to do is to get your car in tow mode, and disconnect your battery by the push of a button. How it does that is the original terminal that is mounted to your positive side of your battery is going to come off.

It's then attached to one of the cables that's going to the operating unit, or to the unit itself. You're going to have another cable that comes off the other side of the unit that connects to your battery.What that's going to do, it's going to block any further current from being pulled from the battery. As far as the installation goes, it is a fairly straightforward, pretty easy installation. You have to find a place to mount your operating unit. You're going to have two cables that come off.

You have your switch that you have to install, and then your ground wire. Other than that, that's all that needs to be done. Now that we've gone over some of the features, let me explain to you how easy it is to actually install.First thing you do is find a place to mount your unit. You can see right up here, passenger side, right up in the corner, we mounted it right to the front side, kind of off to the side of the firewall. The metal's a little bit thin there, so self-tapping screws that come in your kit will not work.

I just put some nuts and bolts through there with a couple of flat washers. Those do not come in your kit. Doesn't matter what size you use as long as they will fit through the hole in the bracket on the unit itself.Off the bracket, you can see the fuse holder. That's going to come down to your switch, which I'll show you where I mounted it here in just a second. You see the two red wires that are coming off the unit, you're going to have one that goes to the battery cable, and one that goes to the battery post.

You're going to have one more wire coming off there, and that's going to be your white wire. That white wire is going to be your ground wire. Now, let me show you where I put inaudible 00:02:22.Before you install anything on the battery post or cables, you want to make sure that the fuse is not in that holder. The gray wire here is running to your switch. Now, you can see, I put it right here. It tells you in the directions what size hole to use. That gray cable is going to have two wires in it. It's going to have a black and a red. They're both going to connect into the back of this. That's going to be your on and off button for the unit. Battery cable, they're going to be marked. It's going to say battery cable.What you're going to do is you're going to pull off the positive battery cable off your battery, then you're going to connect this to it. Now, you can see how this one is made. The only way that I can connect this to that is take off this nut right here on the top, put my cable coming from my unit on there and then put my nut back on. Then, you're going to have the other red one which sticker on the backside says battery post.Now, for this particular battery, because we had to remove this whole post to hook to our battery cable side, that left the positive stud or post on our battery open. We also are going to need to add a battery terminal or put a battery terminal on. Now, you can find it on our website using part number DW05310-1. Then, you can see where I added my cable coming off my unit right on the side there. Now, my ground wire, I just ran it around the back on the ground post right here, added my ring terminal on it and just connected it right to it.Next, we're going to test it out. What we're going to listen for is we're going to listen for the unit to click. When you hear it click, that means it's working. Now that we've tested it, we know it's working, we want to make sure we wrap this up really good with some electrical tape. Now, our kit's going to come with some heat shrink, but it's not going to fit around all of this. I'll zip tie all this together just like that, get it nice and tucked in back here. Clean up our install a little bit.That'll do it for a look at and installation on the Roadmaster Automatic Battery Disconnect with switch for towed vehicles with supplemental braking system, part number RM-766, on our 2015 Smart Fortwo.


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