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SMI Stay-IN-Play DUO Braking System Installation - 2017 Jeep Wrangler

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How to Install the SMI Stay-IN-Play DUO Braking System on a 2017 Jeep Wrangler

Speaker 1: Today on our 2017 Jeep Wrangler we're going to be taking a look at and showing you how to install the SMI Stay-IN-Play DUO Supplemental Braking System. Part number SM99251. Now our braking system is going to apply our brakes on our Jeep in proportion when we're flat towing it behind our RV. This box here is going to be our control box. It's not going to take up much room in our vehicle, and that's really all we're going to see. We do have an on and off switch and that's all we're going to have to do when we get ready to flat tow our vehicle.

Just switch this on and there's nothing else to set up.On the inside of our RV you can see when I push on the brake pedal it's going to activate the brakes on our Jeep in the same intensity and the same time. Now our G-force controller box, since it is a proportional braking system, we're going to need to have this inline with the direction of travel, because it's going to have an inertia sensor in there. It's going to read the deceleration and apply it to our Jeep. We are able to adjust the sensitivity on our brakes, and if we come to this knob right here, we can loosen it up, which will allow us to slide the knob up or down, applying more or less force depending on what we need.Our braking system's also going to come with an indicator light, so whenever the brakes are applied in our Jeep, it's going to light up. I decided to mount it right here so that when we're driving down the road our rear view camera on our RV will know that our brakes are working properly in our Jeep.

Our operating unit we mounted underneath our seat here. We're going to have a couple fittings that are going into the side of the unit here. We're going to have a vacuum line, along with an air line, and a few wires that are going to come out. The vacuum pump is inside the unit, and it's going to restore the car's vacuum each time it applies the brakes. It's going to result in a more natural braking process and have less risk of damaging any parts.Our unit also comes with a breakaway switch, and it's going to attach to our RV with this tethered cable here.

In the event of a catastrophic break in the tow bar or in a case where the Jeep gets disconnected, if we pull this, it's going to apply the brakes at full force and let the indicator light come on, letting us know that there's a problem and it's been disconnected. Now the way the brakes are going to be activated and applied, we're going to have an actuator right here that's going to be hooked to the brake arm. There's going to be an air line that's going to go from our control box to this actuator, and it's going to apply the brakes.Now that we've gone over how everything works, let's show you how we got it installed. First step in our installation is we're going to need to find a spot to mount our operating unit. I'm actually going to mount this underneath the driver's seat here.

I'm going to pull our seat all the way forward. I'm actually going to be able to just slide this right underneath the seat, just like that. Just going to run my wires to the outside, close to the threshold here. That way I can route them to wherever they need to go a little bit later.Our next step is going to be finding a location to mount our G-force controller, and right here on the kick panel on the driver's side seems like it would be a good location. We can take a couple of the self-tapping screws that are provided in the kit and we can screw it right into the plastic. Now our unit's going to come with an indicator light. I'm going to be mounting this to the back of my rear view mirror. That way I can see it from my RV when we're driving down the road. I'm just going to take the backing off of it. It's got some double-sided type tape on the back, I'm going to go ahead and I'm going to apply it directly to the back of my mirror. Then we're going to need to run our wire, and I'm going to follow along the factory wiring here, and go along the headliner and drop it down to the panel over here.You're going to want to tuck your wire behind the panel as much as you can, once you get down to this corner right here you've got a couple different things you can do. I'm going to continue to run the wire, tucking it in between the panels until I get to this side panel over here, and then I'm going to pop this side panel off making it a little bit easier to route my wires behind the dash. I'm going to drop my wire down. I'm going to go ahead and secure it to some of this factory wiring here, that way we don't have to worry about it banging around or moving on me.With our interior components installed and wired, I'll go ahead and show you where and how we connect them. Our red wire coming from our indicator light I wired closest to the brake switch on the cold side of the brake switch wire. That's going to be the wire that only gets power when the brake pedal is depressed. Now the black wire, I went ahead and got my butt connectors and I connected the black wire coming off my indicator light, the black wire coming off my G-force controller, and the black wire coming off my control unit itself, and connected all three together.When I pulled up this panel along the edge here and ran my wires out the side for my control unit, and that's where I ran my black wire running up and then also my red wire from my control unit and went in and connected it to the red wire on my G-force controller box. The white, yellow, and green wires coming off the G-force controller box I ran out the grommet on the firewall. Now the grommet's going to be right down there. A little hard to see but that's where you see those white, yellow, and green wires coming out.I took my yellow and green wires and I tapped into the yellow and green wire for our lighting circuits coming from our RV and then my white wire I went ahead and grounded it at the chassis, right here. It's going to be a factory ground point right against the edge and then I put a butt connector in and I ran it down to the ground that's on my 4-pole wiring that I also had for my lights. Here's where our wire dropped down. It attached to the ground right here at the frame, and then it goes up front to the connector. This is also where the green and yellow wire are coming from, and that's what I mean by the lighting circuits or lighting wiring for our vehicle.Next we're going to need to find a spot to mount our breakaway switch. They do provide us with a nut, bolt, and washer so we can get everything in place, but I don't want to drill into my bumper. What I'm going to do instead is I'm going to take a self-tapping screw and going through my breakaway switch, I'm going to apply this screw right into the bottom of my base plate here, just off to the side of my electrical connector. Our blue wire's going to end up going to our operating unit, with the blue wire coming off of there. Our black and orange wire is going to go to a 12-volt power source, with our fuse holder attached, and then it's also going to connect to the brown wire coming off of our operating unit.My blue and brown wires I ran across the threshold here, and then went up to the grommet that I used earlier and went into the firewall. My brown wire here, I hooked up to my orange and black wire, but then where it came out at the firewall I took one of the extra black wires in our kit and I connected it to the other end of my brown wire and then I ran it across the firewall, zip tying it along the way. I ran it over to my battery to where I hooked a butt connector in so I could put my fuse holder in place, and then I attached it to the positive post of my battery. For right now I'm going to leave the fuse out of the fuse holder.My blue wire, I didn't have enough so I took the excess green wire that I cut off from earlier and I ran it down towards my blue wire and went around my washer fluid bottle and I met up with my blue wire. This wire, this end of the blue wire, is coming from the breakaway switch. With all of our wiring done, I'm going to go ahead and take some zip ties, a little bit of electrical tape, and the wire loom that they provide in our kit and I'm going to tidy everything up and make sure it's not going to be rubbing against anything, or against anything hot.Now we can get ready to work on our vacuum line connections. We're going to want to find the vacuum line that's directly connected to the brake booster. That's going to be right here next to our brake reservoir. One thing I do want to mention, when you go to cut your vacuum lines, you don't want to use a pair of side cutters. You want a clean, flush cut. You want it to be straight as possible, so you're going to want to use an air line cutter or some kind of tubing cutter so you can get a nice straight cut. We're going to have to put in a check valve along with a T. Our T is going to reconnect our vacuum line back together but then the third part, we're just going to go back into the cabin area and it's going to connect to our operating units.You're going to want to try to get a cut in a straight area as possible, so you don't have to deal with the bends. I'm going to come right past this curve and cut it right here. I'm going to take my T, I'm going to insert it into my hose. If you're having a little bit of trouble you can take a little bit of soap, a little bit of silicone spray, and you can apply it to the T so it will slide onto the hose just a little bit easier. Now that our T's in place we're going to come down the hose, we'll put our check valve right about here. We can go ahead and take our cutter, make sure you've got enough room between your fittings here that you're not going to interfere, I'm going to go ahead and cut the hose. When you're putting your check valve in, you want to make sure that the black section of the check valve is going away from the brake booster and it's going towards the engine. You're going to want this green yellowish color going towards the brake booster.Just so it's easier for you to see and we haven't actually bolted our operating unit down, I went ahead and pulled it out slightly. Just wanted to show you where we're going to be making a connection with our vacuum hose. This is where we're going to be plugging it in, so we'll go ahead and take our vacuum hose, we can push it onto the barb fitting. Once we have it connected, we're going to have to run this vacuum line out to the T that's in the engine compartment. We're going to route our vacuum line across the threshold here underneath the factory wiring here, and we're going to route our vacuum line through the same grommet that we've been going through. I'm going to go ahead and route our vacuum line and estimate about how much we need, and give it a little bit extra. Go ahead and cut our tube, cut the excess off, and then we can attach our vacuum line to our T.Our next step is going to be mounting our actuator. This part of our actuator right here, if we loosen up the nuts this is going to clamp around our brake pedal arm here, and the tethered piece right here is going to be drilling into the firewall with the provided self-tapping screw. You want your cylinder and your actuator to be high enough that it's out of the way of the pedal, but low enough so that it still has enough torque and enough pressure to actually move the brake pedal. What I like to do is I like to mount my actuator and then I can take my cable and anchor end, and you're going to want to cut away all the carpet and any insulation, you're going to want to go directly into the metal on the firewall with your anchor point. I'm going to go get this in and get it adjusted, and then I'll show you what it looks like when we're all done.Now that we have our actuator installed, you'll see the grounding anchor is going directly into the metal and I just cut that carpet around it. The cable is pretty straight. It's as level as I can get it, and now they do say that you can have up to an inch of difference between where the anchor is and where your actuator is. Another thing I want to mention is once everything's adjusted and tightened down, you want to have just a little bit of slack left in the actuator here. On our actuator we're going to have an air line fitting here. I'm going to take my 1/4" air line that's in our kit, you're going to want to push it into that fitting, and you'll feel it lock in. I'll go ahead and give it a good tug to make sure it's locked in.We're going to need to route this back to our control unit and it will go into the fitting inside the box. I'm going to do the same thing that I did with my vacuum line. I'm actually just going to tuck this underneath. Push the seat forward. Make it a little bit easier to see what I'm doing. The air fitting going into our control unit is going to be right next to our vacuum line right here. I'm going to go ahead and give myself a little bit of extra room. I'll go ahead and cut my air line tube, and then we can plug it in. Give it a nice little tug to make sure it's not going to come back out.Now with all of our connections made, we can go ahead and start tidying up all our wires and putting all our panels back. Now that all the panels are back in place, I'm going to take a couple self-tapping screws and I'm going to screw it into the side plate here. Just got a couple holes, I'm just going to go right into the floor. Now with panels back in place and everything tidied up, we can take our 20 amp fuse and we can put it in our fuse holder. Once we have this in place, we can go ahead and test our system to make sure everything's working properly.That will finish up our look at the SMI Stay-IN-Play DUO Supplemental Braking System. Part number SM99251 on our 2017 Jeep Wrangler.



cool , so the left right signal light will be working as well?

Etrailer Expert

Chris R.


All your signal lights on the towed vehicle should work during flat towing - but you'll need to install a separate wiring kit for this purpose. The Roadmaster # RM-15267 is a really good solution.

Maurice B.


I tow a 2018 2-0 turbo Wrangler Unlimited JL with a 2017 Newmar Baystar 3124 Gas Class A motorhome. I have installed the SMI Duo Braking system with Blue Ox Base plate and break away break. Question: because I have a full Bra cover , which includes the windshield, I need to install the brake indicator light in my coach. can you direct me to installation instructions or a detailed video on how to do this? I viewed 1 video which showed a wiring solution on a vehicle which required the battery disconnect to tow. This not my understanding for my situation.Thank you guys for your assistance.I did the install with your assistance and my mechanic gave me an A after he inspected my work.

Etrailer Expert

Rachael H.


We do have the SMI coachlink 9000 transmitter system (# SM99945) that is a brake light indicator installed in thecoach, and I have included the installation instructions, and an installation video we have on a similar Jeep for your reference.

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