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Roadmaster 6-Diode Universal Wiring Kit Installation - 2008 Honda Fit

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How to Install the Roadmaster 6-Diode Universal Wiring Kit on a 2008 Honda Fit


All right, today on a 2008 Honda Fit we're going to install part number 154-792-118158. This is a Roadmaster 6 Diode Universal Wiring Kit for towed vehicles with separate lighting. To start of, let's go ahead and open the back hatch. Now we're going to remove and loosen some interior components. First off, our floor covering for our spare tire, we're just going to scoot that forward. Now we need to go ahead and remove our threshold. It's a good idea to peel back on the weather strip just a little bit, and using a trim panel tool, pop it loose.

Now the panels behind the tail lights we'll go ahead and remove as well. All right, we're going to loosen up this panel here, and we'll go ahead and remove this screw. This pulls back pretty easy. Now we just need working room to run our wires, you don't want to really completely remove it. We're done with our driver's side, let's go ahead and do the same thing on our passenger side. Okay, now we've got our vehicle ready to install our wiring. Okay, now when we do wiring on a vehicle that's getting towed behind a vehicle, every time we put electrical or power into the system we need to use a diode.

Now we'll go ahead and find the circuits we need to use and install our diodes first. All right, to help us find the wire initially, we'll just turn on the running lights and you can see how the socket glows in the background, so for running light circuit, we know that this bundle of wires is what we need. We'll go ahead and remove the loom from our wire so we can work with it. Now we've got easy access to the wires. We'll use a light tester to verify which wire it is. We'll take our tester and ground to the latch, and we'll go ahead and check to see which wire.

So it looks like a red wire with a black stripe and silver bands is going to be our running light circuit. So we're going to cut this in half, add some terminals to each end, and then install our diode. Here's our diode, and here's the terminals that come with it. We'll go ahead and remove the terminals from the diode and then go ahead and put them on the wires, okay Now we'll go ahead and put a diode in place. Now it's labeled input and output. So the input will be from our vehicle into one of these tabs here, and then our output always goes towards our tail light. Of course this is the unit that goes to the tail light.

And then we've got one more tab for input, that will be fed in from our RV, when it tows it, but we'll leave that one alone for now, okay Now we'll go ahead and look for our brake signal, and we'll basically do the same thing. All right, now we'll just temporarily push it back into place and we'll look for our brake signal. So it looks like our brake signal circuit is going to be white, with a black stripe and silver bands. Just like before we'll go ahead and add a diode. Just like before, our input from our car, back to our tail light. Now for this set of wires we'll go ahead and mark them. "B" for brake, and this is our running lights, so they'll be, running light, "RL". We'll set those aside for now. Now we'll go ahead and look for our turn signal. All right, we'll go ahead and do the same thing, we'll see which wire we need for turn signal. It looks like for our turn signal it's going to be green, with a red stripe and silver bands. Okay, just like before, our output will go to out, and one of our inputs. All right, we'll make this one left turn. Now basically we're done with our driver side, we're going to repeat the same process over on our passenger side. One more time, let's go ahead and look for our running lights circuit. Now we're going to sneak out our wire harness from the back side to get easier access to it. So for our running light on the passenger side, will be red, black stripe, and silver bands. Once again, out to our tail light, and either input, it doesn't matter. Let's go ahead and mark this one for running light circuit for passenger side. All right, now let's go look for our brake signal on passenger side, and it looks like white, with a black stripe and silver bands. All right, out to our tail light, and input. All right, now well go ahead and look for right turn signal, and again we'll go ahead and turn it on and look for a socket to glow and then we'll go ahead and pull it out. It looks like our right turn signal is going to be green with a yellow stripe. Output, and input. Our next part is to go ahead and install this component here. This is the input that will be coming from our RV so we'll be working with this side for output going to the car and the cars wiring harness. These will all go out to our diodes. We'll go ahead and start off our first wire, which will be our easiest one. This will be left turn signal. We'll go ahead and put a terminal on it. So we're going to go ahead and run our wire underneath the plastic to our diode, and we will simply connect that to our input on our left turn signal. Next up is our red wire. This is for our stop light, and we'll go ahead and follow that around as well. Okay, this will go to our brake light, so we'll run it to the input there. Now we have our brake wire going over to our driver side, we also need to run this over to our passenger side, so we're going to get an extra length of wire. We use a quick splice connection to attach to our red wire, and then go across to the other side of the car. Now we'll be using part number 34466000-5 This part number has 5 of these splices and it should be more than enough. We'll take a quick splice connector, attach it to the wire we're going to tap off of, take our new wire that we're going to extend it with, put it right next to it, and just squeeze it together. Occasionally you'll mess one up, so it's a good idea to get some extra terminals in case you mess up. We'll take this end of the wire and attach it to our brake signal on the passenger side. Now since the terminals are unprotected, let's add some electrical tape, just to give it and extra layer. Next we'll go ahead and work with our green wire. It's a little short so we'll extend it as well. We'll use another piece of scrap wire, and we use a butt connector, part number 05731-5. That added plenty of length to it. Then we'll go ahead and add our terminal to it. So we'll go ahead and hide this behind our plastic and go up to our turn signal. Input for right turn. All right, just to recap what we've got so far, we've got our left turn signal, our brake signal, and our right turn signal. Now we're also going to need running lights. Now running lights aren't included in this module, that will be part of the wiring harness that goes up towards the front of the car. So, to do that, we're going to need to make a running light circuit. We're going to run it from our running light circuit on one side, and we're going to run it over to the other side, so we'll have a wire going for both diodes for both tail lights, and then just like we did on our red wire, we use a quick splice connector, and that will supply our running lights circuit. Okay, a quick idea is this role of wire is what we're going to use to connect up to the front of our vehicle. Now this has more than enough length than we need, and plus, we need to cut off one end, so the rest of this wire can be used as our extension for our green and brown wires. So one end we're just not going to need, so we're just going to cut it off. It might be a good idea to keep the cap for future reference. So let's go ahead ahead and take some of our wire, enough where we can go from each end, and then some, and we'll just cut off what we need. Well need our brown wire. We'll go ahead and add a terminal. This will go to our passenger side. Okay, and our other end will go to our running light diode here. When you notice, when you get with the diode kit, when you get one of these terminals that's extra big. The idea is you put one of these two brown wires into it and it makes the junction. We could easily do that, but we're using a quick splice connector so you can see it our in the open. We'll just use a smaller one since we don't need to use our yellow one for a junction. We're almost done with the back of our vehicle. Let's take a few moments and go ahead and reinstall our wiring that goes in back of the tail light. This end will go to our wires in the back right here, and we need to run it to the outside, however the grommet we are going to use, the hole isn't big enough to accommodate this, so we're going to go from underneath and run this up through back to our wiring, and this will stay on the outside. To do that, there's a grommet on the driver's side, from underneath we'll have to get access to. All right, now if you look underneath the vehicle, you'll see this piece of sheet metal right here, okay If you look on this edge and feel towards the top, you can find a grommet. Just pull it out, and we'll make a slit in it, and then we'll go ahead and run our wire through it. Let's go ahead and take this and put this back into the body, then into the inside. We'll go ahead and feel for a little opening and go ahead and just push our wires in, a nice healthy chunk of it to make sure we can find it on the inside, then reinstall the grommet. We can pull out the wire, and let's go ahead and run it behind our plastic, okay We'll go ahead and split our wires and get it ready to work with. We'll split our wires up. Remember that brown wire I was talking about a few minutes ago Let's go ahead and make our connection. This is our wire that went from left to right, and now this new wire we're adding to it, will supply the power. Okay, so now, on our wire harness, three wires left: right turn, left turn, and our ground. Get the ground out of the way, we'll leave that for the last. So at this point we need to connect them up to our input for our module, so it's going to be a simple color for color. We'll use the yellow butt connectors that came with the kit with the diodes for this. Okay, this will be from the RV and into our module. Now let's go ahead and deal with our white wires or ground. For our white wires we'll use a couple ring terminals, part number Dw05702-1, and we'll go ahead and use a self-tapping screw to attach to the sheet metal right here. It's a good idea to use the sheet metal that overlaps so you have plenty of material to dig into. All right, now all of our electrical connections are done at the back of the vehicle, we'll leave all the interior pieces open, so that way we can, after we test it, we don't have to tear it all apart again, in case something's amiss. Now let's go underneath the vehicle and run our wires from the back to the front. When we do that we want to stay away from anything moving, like suspension components, and anything hot like the exhaust, and going up front we want to stay away from the steering components as well. We'll lower this panel and let it go ahead and hold up our wire for us. We went underneath the bottom of the car, and reached in and pulled out our wire from the grill, where we have plenty of it left over. In this case, you can see how we came down here and zip tied as we needed to go towards the front. We ran it behind some plastic holders and shields to help hold up our wire and just followed some existing lines all the way toward the front. We've got our wire routed up to the front of the vehicle. We'll go ahead and take some extra steps to run it the way we want it. I want mine over the base plate a little bit, and then we'll take our extra and just bundle it up, just make sure we leave enough for reasonably easy access to our forepull 00:17:22. All right, now when we're not using it, typically our wiring harness can just sit back in the grill here, just tucked away, and when we need to use it, just pull it out. So now, we've got everything ran and electric connected, let's go ahead and apply some power to it and make sure it works. First we'll go ahead and try our running light circuit. Now we'll go ahead and try our left turn circuit. Okay, now our right turn circuit, and then our brake circuit. We've verified everything's working, let's go ahead and put the rest of the vehicle back together. Take a moment to take our module and attach it to the sheet metal by the spare tire. Okay, we'll take adhesive and we'll go ahead and put this into place, and then we'll simply take our wires and secure them out of the way. Okay, now one thing we did on here is, actually, we kept our zip ties a little bit on the loose side so when we put our cover back in place, they'll all press down, because it's going to be a really tight fit. We try to stay the same thickness as the factory wiring. Okay, and with that, that will finish it for our install of part number 154-792-118158 on our 2008 Honda Fit. .


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