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SMI Stay-IN-Play DUO Braking System Installation - 2017 GMC Sierra 1500

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How to Install the SMI Stay-IN-Play DUO Braking System on a 2017 GMC Sierra 1500


Today on our 2017 GMC Sierra 1500, you're gonna be taking at look at, I'm gonna show you how I install the SMI Stay-IN-Play DUO Supplemental Braking System, part number SM99251. Here we have our G-force controller. This is gonna allow us to turn our system on and off. It's also gonna allow us to adjust the sensitivity of our braking pressure. When mounting this, it can be mounted on the driver or passenger side. You just gotta make sure that it's level with the direction of travel.

This is what our operating unit looks like when it's installed. And you can see here, we have it mounted in this extra battery tray. You just wanna make sure, if you don't have this extra battery tray, you mount it somewhere where it's not gonna get soaked with water. It can get wet, it just can not be soaked.Your operating unit is gonna give you all the power for your breaking system to function. You have your vacuum line that hooks directly into the braking system on your vehicle.

You have your airline tube that connects to the actuator mounted on the brake pedal. And you're gonna have a couple wires, two of them are gonna have to run inside, two of them are gonna run down to your break-away switch. This is our break-away switch, what this is gonna do for you, is while your vehicle is being flat-towed, you'll have a cable that is hooked up to this wire here, and in through the back of the RV. If this pin is ever pulled, it's automatically gonna set the braking system off in your GMC, bringing the vehicle to a stop. If we didn't have this, if your vehicle came disconnected, your vehicle would just bounce around down on the highway.

We don't want that to happen. This, if the vehicle comes disconnected, it's gonna pull the pin and operate the braking system.Now, the Stay-IN-Play DUO is gonna be one of five main component is a flat-tow setup. The other four are gonna be your safety cables, your tow bar, your wiring, and your baseplate. To start your installation on your Stay-IN-Play DUO, you need to find a place to mount your operating unit. Next, off of your operating unit, you're gonna have four wires.

You're gonna have a black and red wire and a blue and brown wire. Take your black and red wire, and you're gonna set it right up here to the side towards the firewall of the vehicle. Your blue and your brown wire, you're gonna route down and to the front, right behind the bumper, or where your bumper would sit. Next, you wanna mount your break-away switch. You want this as close to the center of the vehicle as you can get it. I woulda had a hard time putting it in here 'cause I couldn't get the nut on.So, there was an open spot here in the license plate bracket. I just drilled a hole straight through it and you can see how I have it in there. And, you can take it, fold it underneath your bracket when you're not using it, so it's not sticking out. So, you can see, off our break-away switch, we're gonna have a blue wire and an orange wire with a black stripe. What I did, is I just drilled a hole straight there, and bringing them right in behind my bumper. You're gonna take your blue and your brown ire coming from your operating unit, you're gonna connect your blue wire to the blue wire coming off the break-away switch. You're gonna connect the brown wire to the orange wire with the black stripe. Now, this wire has to be extended up to the battery. So, how I did it was, I cut it short, tied them together like this. I am using heat-shrink butt connectors, if you don't have any of those, 'cause those are not gonna come in your kit.You can find them on etrailer.com. What I did, is I just took an extra piece of wire, brown wire here. I'm gonna extend it up to my battery 'cause my battery is on my passenger side. Next, you're gonna have a roll of airline tube in your kit. There's a grommet right here on your firewall. You take a small screwdriver. I actually slit this side. And run your small screwdriver through the inside first. Once you make your hole, run your airline tube inside the vehicle. We're gonna use this to pull our wires back and forth. You can see this bundle of wires here that's going in and out. Your red and black wire that I had you hang over to the side, you're gonna take that, and you're gonna tape it to your airline tube. And you're gonna use your airline tube to pull that wire in, or pull those two wires inside the vehicle. Next, you're gonna mount your G-course controller, you're gonna make sure that it's level with the direction of travel.It's either gonna be mounted on this driver side kick-panel, or the passenger same side kick-panel, which would be the center console. Again, make sure it's level when you mount it. It comes with two screws to tap it into your panel here. Off the back of that, you're gonna have a green wire, yellow wire, white wire, and a black wire and a red wire. Next, you're gonna take your red wire coming from your operating unit, red wire from G-force controller and you're gonna connect them together. This butt connector does come in your kit. Once you've made that connection, you're gonna take your yellow wire, you're green wire, and your white wire, use your airline tube. Tape those to your airline tube and pull them out through the grommet into the engine compartment. Next, you wanna mount your indicator light.Your indicator light in this case, is gonna let us know if our vehicle comes disconnected from our RV while we're traveling. If it does, the brakes are automatically gonna be applied in the towed vehicle or in our GMC. And this light is gonna come on, so we can see it in our rear camera on our RV. To run it, I took my wire, and I ran it right up above my head liner, I came right over to the aid pillar, I popped this top part off, there is an airbag in here, so you wanna make sure when running that wire you run it back behind the airbag so that it does not interfere with the airbag deploying, if it actually has to come out. Anyway, you run it over, I pulled off this rubber seel and ran it right behind everything, right down the backside edge, or this outside edge of my dash. And then, went down underneath where my G-force controller is.Now, I'm gonna try not to confuse you. Your red wire that we ran in earlier with our black wire, you're gonna connect to the red wire coming off the G-force controller. The black wire coming off the G-force controller is gonna connect to the black wire coming off your indicator light and the black wire coming from your operating unit. You can see how we have three of them tied together here. Next, because we're gonna be installing a battery disconnect, normally the red wire in your instructions is gonna tell you to connect this red wire from your indicator light to your stop light switch. However, we can't do that because we're gonna be disconnecting the battery and all power. So, we're running this out to our break-away switch. What I did, is I added red wire onto it. Took my green wire, my yellow, and my white wire, and this red wire that I just connected, and use my airline tube and pulled them all through the engine compartment.Now, my green, my yellow, and my white wire, I tapped it into my dialed wiring that was previously installed. You can see I just color matched all of them. The white wire, the white wire is your ground. So you we're gonna have to take a third one, take it off of that and you're gonna ground it to the body somewhere. The red wire that we brought back out from the cab of the vehicle, from our indicator light, we hooked that to the blue wire coming off our operating unit that's going down to our break-away switch. Once you get all your wires connected . And then your airline tube, one side of your airline tube's gonna connect right here into the front side of your operating unit. The other side that is inside is gonna connect to the actuator, which I'll show you here in a minute. But you can see how I have all my wires ran, I like to run them all the same direction, or in the same area because what I'm gonna do when I'm all completely finished, is I'll take some wire loom and I'll cover all of that up.And make it all look as clean as possible and as factory as possible. Here's our actuator and it's gonna mount to the brake pedal arm. You're gonna have a bracket right back here, it's gonna come with a self-tapping screw that's gonna attach to your firewall. What you want, is you wanna mount this to your firewall in a direct line, from where the back of this is when the pedal is compressed. So, if I push on the pedal, this'll kinda drop and then go in a straight line, straight toward it. When doing that, you're gonna have an adjustment screw, it's an Allen head screw, right here on this back side, that's gonna tighten this wire inside of the bracket. Before doing that, tighten it just enough to where you can move this just a little. Try and get an idea of where your firewall or where this is gonna sit on your firewall and you mount your actuator.What I like to do is mount my actuator, or put my actuator on my brake pedal first, do it loose or do it tight enough where it'll stay there, but loose enough where you can adjust it if needed. And then, you're gonna adjust the length of this to where you have about a 1/4" of play in your line. We don't want this so tight that the brake pedal is being pushed. Once you have found that, take your Allen wrench, tighten that bolt up so that this wire will not pull out anymore. If it pulls out, then your brake pedal is not gonna depress when the braking system is operating. Once you have this mounted and to make sure that this is tight, you can always loosen these four bolts and slide this in or out. As long as you don't have it set one way or the other, you can adjust it to put tension on that wire if needed. Once you have that done, you're gonna take your airline tube, you're gonna cut it to the right length and it's gonna go right on this end.You wanna make sure that when mounting this, it is up high enough that whoever is pushing on the brake pedal, their foot is not gonna hit that because that part is plastic and it will break. Make sure it's cut flat, it's not pinched or kinked or cut at an angle. If you don't have airline tube cutters, you can find some on our website here at etrailer.com using part number F9009. Now, how our actuator works, is when our GMC is being flat-towed behind our RV, we apply the brakes in the RV. It activates the brake lights. When it activates the brake lights, that signal is put into our operating unit, which causes our braking system in our towed vehicle to operate. When it operates, what it does, is it sends air through this airline tube that's connected to the top of this actuator. It's gonna fill this cylinder with air, it's gonna push this cylinder out, this bracket at the end of our cylinder is gonna pull back to that bracket on our firewall, in turn, applying the brakes in our towed vehicle.Now, I'm gonna clean up my install here. Bundle up my wires. There's some existing wiring or factory wiring right up here on top, I'm gonna zip-tie them right to that. And I'm gonna take a little bit of wire loom and this is completely up to you, I'm gonna cover up these wires. Just down here at the bottom, like that. Next, we're gonna run our vacuum line to the line coming off our brake booster. This line, you should only have one that comes off your brake booster, it runs to your engine. Trying to find the flattest spot to connect it. This is gonna be the best spot right in here. This is my vacuum line, it's gonna connect right there, coming off the operating unit. I think I'm gonna route mine with my existing wiring here. So, once I cover it all up and keep everything together, I'm gonna route it just like this.What we're gonna have to make, is we're gonna have to make a T-fitting to fit in the center of this when we cut it off. So, kinda get an idea of how long you're gonna need, I'll take my tube cutters and cut that section off. And we're gonna use this part. So, I'm gonna show you right now how to make the T-fitting that we're gonna be placing inside of here. In your kit, you're gonna need these two because we have a hard plastic line. This is gonna be your T and you're gonna need your check valve. We're gonna make that fitting out of this hose. What we need to do, is we're gonna cut. See, I have about 3" or so cut off. So, we'll cut three of those and you're gonna place one on one side of your T-fitting. Try and get that down as much as you can. What you might need to do is take a pair of needle nosed pliers, stick them down in there and stretch the end of that hose out a little bit.That will make it much easier. And then, spray some soap and water on it, soap and water works really well. And we're gonna take our check valve, black side's going towards the engine. So, we're gonna stick it on like that, green side facing towards the T. Now, we're gonna take these two, we're gonna stretch out our ends and we're gonna slide these over the plastic hose, over the plastic vacuum line on the truck. Once we do that on each side, we're gonna take this and we're gonna slide it in onto it like that. We're gonna run these clamps onto our plastic vacuum line and then our hose coming from our operating unit or vacuum line coming from the operating unit, will hook right into the bottom of our T. Now, we're gonna cut our vacuum line. We're gonna cut it right here in the center, but I'm gonna cut a little bit of extra out of it. Needle nose pliers or something, and we're gonna work that in like this.And then pull that. We're gonna do a half twist or quarter twist, and we'll just work the end of this hose off or out. Kinda get it stretched out enough. Take some soapy water. I'm gonna spray it onto my plastic line, spray some in our hose there. Want to get that slid on there. Make sure you get it on there far enough, when you put this on you tighten it down. It doesn't squeeze the end of this plastic tube and cause an air leak. And we're gonna do the same thing to the other side. And we're going to take our fitting, black side's gonna go towards the engine, white side's gonna towards the booster. Push that on there. Looks like we got quite a bit on here. Like that. We wanna take our other end, just like that. And our brown wire, I just ran it right up over top of my frame rail. And then right up behind this edge of my . it's kind of a brace that kind of holds all this together, right back through it and then up . I don't know if you can see it very well.See right there, it's pretty open down in there, so you can get the wire up pretty easy. And I ran it underneath everything, right up to this side. Next, we'll take our fuse tap, make sure the fuse isn't in it. We're gonna cut it in half. Strip back both ends. One end, we're gonna add a ring terminal and then we'll set that aside for a second. Take our brown wire here, we're gonna pop this cap off of our battery, should be able to just pull it, just like that. And next, you're gonna connect it right here. Before I do that, I'm gonna add a heat shrink butt connector to the one of my fuse holder or the other end of my fuse holder. I'm gonna take my wire, cut it down a little bit. We'll take our heat source, shrink up our butt connector. Go ahead and put the ring terminal right underneath that nut there. 10 millimeter socket. Remove our nut.And, what it looks like is that is not meant to come off. So, I'll show you how to connect this onto that without taking the nut off. We're gonna take a ring terminal and we're gonna cut a gap in it like that. We're gonna slide this right on there. Then we'll tighten it back down. We got that. And, add out fuse, reinstall our cap, just like that. Now that we have all of our wiring connected. We're gonna test it out to make sure it's working properly. What we should here when we pull out break-away switch, we should hear our operating unit come on. And our red light on our mirror indicator light come on. When our operating unit comes on, the actuator hooked onto our brake pedal should also be pulling our brake pedal through the firewall. Or at least in the direction, as it's applying the brake. Now, that we know everything's working correctly, we're gonna clean up our install, cover up all of our wires with the wire loom that comes in the kit.You can see here, this is where all of my color wires we're running back to my firewall in through my grommet. Color wires coming out of my operating unit here, and going down to the front of the vehicle. Once you've got your install cleaned up, go ahead and put your fascia back in place and your grill. That'll do it for a look at an installation on the SMI Stay-IN-Play DUO Supplemental Braking System, part number SM99251 on our 2017 GMC Sierra 1500.


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