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Roadmaster Universal Diode Wiring Kit Installation - 2017 Ford C-Max

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How to Install the Roadmaster Universal Diode Wiring Kit on a 2017 Ford C-Max


Hey everyone, Shane here with etrailer.com. Today, I have a 2017 Ford C-Max and I'm gonna walk you through how to install Roadmasters Diode Wiring Kit. Diode Wiring Kit is gonna be more of a permanent install, and what it does, is it allows the motor home to transfer light signals back to your towed vehicle so that you're legal and safe. Whether it's braking, turning or driving at night. Once this is installed, the only thing you're gonna have to do is connect the umbilical cord from the front of the vehicle, to the back of the motor home. It's gonna be completely hidden.

Diodes are gonna mount behind each tail light. You're gonna connect the factory wiring. Now, what the diodes do is, they protect the factory wiring on the vehicle from back feed. If there's a short between where the diodes hook into your factory wiring and where they come out of the motor home, the diodes are gonna stop that short from getting to your factory wiring and causing more damage. Now, as far as some of the other kits that are available, for instance, bulb and socket.

Bulb and socket is gonna require a hole to be drilled in the tail light, which is not my favorite thing to do. Another one would be magnetic. Magnetic lights are easy cause all you do is set 'em in place, but you have a bunch of wiring hanging off your vehicle. Then you gotta find somewhere to store all that when you're not using them. So my opinion, I really like the diode kits.

Once they're installed, you don't have anything to do, again, other than hooking up your umbilical cord to the front of your vehicle and back of your motor home. As far as the installation process, installation process is very simple and straightforward. You simply run your wire from the front of the vehicle, back behind each taillight, connect your diodes, hook up your 6-pole plug on the front and you're basically done. Now that we've gone over some features, we'll walk you through how to get it installed. To start our installation, we're gonna come under our hood.

Where our fascia comes inside, we're gonna have four pushpin fasteners, we need to remove those four. All we're gonna do is pry up on the center and then pop out the base. There should be a little slot that you can fit a flathead screwdriver in, trim panel tool if you have one, to get the center of it up. Next, we're gonna take a 227 Torx bit, right behind our fascia next to our headlight, there's gonna be two bolts. We're gonna remove the inside one. We have one of these on each side. Next in each wheel well, 227 Torx bit, we're gonna remove this bolt here. We're gonna have one right here, and then right on top, going from our fascia to our fender, there is a pushpin fastener that needs to be removed. Your gonna do this on both sides. From right up here, this pushpin fastener, may be easier if you get a Flathead screwdriver, or you have a pick like this, so you can pull that center down a little bit. Next we're gonna come underneath the bottom edge edge of our fascia right here. We're gonna have six pushpin fasteners we need to remove. One here in the corner, one here, we have two in the center and then two on the opposite side. We want to remove all six of them. These, your gonna remove 'em the same way you did on the top ones, underneath the hood. What I like to do, is before I start pulling my fascia off, is where our front fascia meets our fender, is take some painters tape, and cover those two edges. So that when we are putting it back on or while we're taking it off, if these two pieces hit each other, we don't take a chance at chipping any paint. Next we can start pulling off our fascia. It's a good idea to have an extra set of hands, but if you don't, take the box that your base plate comes in, set it underneath the bottom edge of the fascia. We're gonna start on one corner and work our way to the center. Keep in mind, sensors, fog lights, or anything like that are gonna be plugged in. So as you're taking it off, you just don't wanna pull it off. Now what we're gonna do is, you're just gonna kind of pull out on it. You have a couple of clips in here that, may not want to release, and it's hard to get your hand in there. So it may be easier if you have a long screwdriver or something there, go in and just kind of push up on it and it will release it. So if you look right here, this piece goes over the top of that. All you can do is reach in with something long, pull that up just a little bit and it will release that. And we'll do the same thing on the other side. On our driver's side, we're gonna have a large plug here. You need to disconnect that. Sometimes these plugs don't actually, it came off easy. Sometimes these plugs can be a little bit difficult to get apart because they're out in the weather. And then push down right there, and then pull the two apart, and we'll set our fascia aside somewhere safe. You can run your wire from the front, the back or the back to the front. I find that it's easier to run it from the front to the back and then split your wires to each taillight. I did it because I taped some extra here on the front. Underneath this panel there's a hole right in the backside of it. There's a bolt here and a bolt here. If you take those two bolts out, that'll give you enough room to get back in here, around here underneath this panel, around my frame rail, cause I wanted to stay away from my engine side here. Right up here you have your brake line. You can see it. I went over the top of that. Stay away from my CV joints, Our axles. Went around my frame rail here, this panel, there's a bolt right here. I ran up above that and then came down to here. Once you get here, you can take this cardboard panel and kind of pull down the edge of it. Or you can take these out with a Phillips screwdriver, Pull on the edge of it and you tuck your line in all the way down to this end. There's another panel here so I fed my wire in and it came out the backside here. Once you get to the back side, you have a hard line here, went over the top of it. Over top of this brace, over top of my rear axle. You have a hole in the frame around here, and one on the outside. I fed it into that hole and out of this one, otherwise my line would have been coming straight across here. This is gonna keep it up. Run it over, zip tied it here, pull your white wire loose, cause we're gonna tap that right to the frame rail. Then what you're gonna do is you're gonna split all your wires apart, to this point. Your green wire, you can route it across over to the passenger side. How I did it, is you have your bumper beam here, right in the center and you have one over there. I just went over to the top of all of it to right here. And we're just gonna leave that hanging. We're gonna cut our white wire here. This is gonna be our ground. We're gonna hold on to this white wire, just extra, just in case we need it later. We're gonna strip back the end. We're gonna add on the ring terminal. It comes in the kit. And we're gonna take one of our self-tappers and go right into the frame rail right there. It doesn't really matter where you put it as long as you're on a metal surface. And if you really wanted it to, you can run your white wire up with the brown and yellow wire and put it in the body of the vehicle, up behind the tail light. I find it sometimes easier to do it this way. From here, we need to remove our taillights. There's a couple of ways you can do it. There's a rubber plug on the very bottom, but there's a bunch of padding inside and you're gonna have to try to get through., Not a whole lot of space there. We're gonna remove the tail lights and on the inside of the panel it's gonna look like this, pop it off, take a flashlight and look back there. You're gonna have two nuts that are gonna look like this. Twist those off and you're gonna pull straight back, right in this corner there's another pin that goes in. You put a trim panel tool, right in this edge and you just kind of work it out. Eventually that will pop out. And then we can disconnect our wiring to our tail light. And we'll set our light aside. So what I'm gonna do is, because this plug actually lives inside there, but this hole's big enough, I'm gonna bring my wires up. I'm gonna run them through the hole, and my diodes are actually gonna mount inside. Next we're gonna take a pull wire, I'm gonna use an airline tube, really use anything, wire hanger if you have one. Anything that you can get dropped down to where it'll come out the bottom side. You wanna make sure, there's a bracket right here that goes into the body. Make sure you're going to the outside cause if you come to the inside your wires are gonna cross right where your taillight attachment point is there. And we don't wanna damage the wires. Now I'm just gonna take my wires, my yellow and brown wire, and tape it to my pull wire. And then I can pull them back up. Then we can take them and we're gonna feed them right through that hole to the inside. Now our brake and turn signals are separate on this vehicle. So what we need to find, is we need to find a brake signal because the wiring that we just ran are combined. We're gonna find the brake signal, and we're gonna find the running lights signal. Brakes. Off. On. We know that this brown wire is gonna be our brake signal. Now we'll check for our running light signal. Off. On. Off okay. That means the brown wire is the break. This, looks like a purple wire with a green stripe. It is going to be our running light signal. We're gonna do that same thing on the opposite of the vehicle. So it doesn't matter which one you start with, we're gonna start with the brake wire. I'm gonna cut it back close to where this quick connect is, because remember this has got to go back outside to connect to the taillight. You wanna make sure we get plenty of room there. So we'll cut that. We're gonna strip back both ends. We're gonna add on a blue spade connector, and take one of our diodes. The single side, it's gonna go out towards the light. The double side is gonna go back to the wiring. That's gonna re-complete the circuit. We'll take our yellow wire, which is our brake and turn signal, we'll cut it to size. We're gonna strip it back, add on another blue spade connector. We'll add it on to the second terminal on our diode. That's gonna give us our brake and turn signal from our motor home. Do the same thing with a running light signal. We'll do the same thing with this end, with the exception, that our running light wire coming from our diode kit is gonna be just a little bit different. We're gonna take our running light signal from our diode or our brown wire. We're gonna cut it, or we're gonna strip back both ends of these. We're gonna put them together. You're gonna have a large yellow spade connector. Add it on. Then do the same thing with our diode here. Single side goes towards the light, double side goes to the factory wiring in the vehicle. We're gonna take this brown wire, this extra, and we're gonna run it back out through the hole. This brown wire is gonna get routed back down and it's gonna follow the green wire over, to give us our running light signal on the other side. Before we get our diode to mount on inside, and we may end up just zip-tying them to some factory wiring in there, we just don't want them bouncing around. We're going, go ahead and connect our tail light. Get it slid back into place and see how much room we got. So we don't have a whole lot of room in here. So wires are not really too long. On the backside of your diode you're gonna add two-sided sticky tape. What I'm gonna do is I'm gonna take one, I'm a flip it over and stick it to the top side of the other one. Then we have some factory wiring that runs right here, if needed to, I can run a zip tie, right around this factory wiring down here. That'll keep those from moving around. Now our wire colors on our passenger side are gonna be the exact same color as the driver's side. The only difference between driver and passenger side is you're gonna have a single brown wire going into your running light signal instead of two. Other than that, everything is exactly the same. Once you get your diodes put in on your passenger side, reinstall your tail light, and we can go up front. We can temporarily install our six pole plug, to test everything out and make sure it's working correctly. The front of the vehicle we'll strip back each one of our wires, we'll take our plug, and the backside of it, it's gonna be marked. RT for right turn, LT for left turn. DD for ground, TM for running lights. And you had two extra pins, which in another video, we're gonna be installing a battery charge line, which would go right to that center pin. These screws on here are very small. You don't want to take them out all the way. You can use a Flathead or a Phillips. I recommend using a flat head cause it seems that the small Phillips will tend to strip the heads out a little bit. Let's start with our right turn, which is our green wire. As I mentioned before, we're just temporarily installing this so we can test it. When you go to install it once your fascia's installed and you go to put this back on, this will get mounted here. You wanna make sure this boot goes on, or you send your wires through it before you connect them. This boot will slide right over the top of it. Run some electrical tape around there, wire loom on here and fill in between these connections with some silicone. Because if this gets any moisture, what happens is they will cross feed and you will get a short. So for now, we're just gonna leave it hang like this. We'll connect our cable to it and test everything out in the back. Now we're gonna test out our lights, using an alternate power source, which is gonna simulate being hooked up to your RV. Tail lights. Left turn. Brake lights Right turn. Once you've tested it out, you know it's working correctly, install any other components you may be installing. Re-install your fascia in reverse order from the way you took it off. So that way you only have to trim around it once and you're ready to go. That's gonna do it for a look at an installation on Roadmasters Diode Wiring Kit on 2017 Ford C-Max..


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