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SMI Stay-IN-Play DUO Braking System Installation - 2015 Smart fortwo

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How to Install the SMI Stay-IN-Play DUO Braking System on a 2015 Smart fortwo


Speaker 2: Today on our 2015 Smart ForTwo, we're going to be taking a look at and showing you how to install the SMI Stay-IN-Play DUO proportional supplemental braking system, part number SM99251.This is what our Stay-IN-Play DUO looks like when it's installed. This is going to be one of five main components in a flat tow setup. The other four are going to be your wiring, your base plate, safety cables and your tow bar. What the Stay-IN-Play Duo is going to do is, if you're a car comes dislodged or come separated from your RV while it's being flat-towed, the Stay-IN-Play DUO is going to activate the brakes in the car and bring the car to a stop, in turn not hurting anyone else on the highway or on a roadway.How it does that is the breakaway switch. When this is pulled, it activates the brakes in the car. Most states require a braking system in a vehicle while it's being flat towed.

The braking system is a nice safety feature on the vehicle when it's being flat-towed. Reason is, if you think about how heavy a car is, when it's being flat-towed, there is nobody inside of it to try to slow it down or stop it.This system's going to do that. If this car didn't have it in there, basically it would be, you know, you're driving 70 miles an hour down the road, this comes off of the RV, this becomes a rolling missile and can hurt a lot of people, so I recommend, highly, highly recommend getting a breaking system, if you are flat-towing your vehicle.Let's go a little bit more into how the braking system works. You're also going to have an actuator that hooks onto your brake pedal and mounts to your firewall. When the car is being flat-towed and you apply the brakes in the RV, there's an airline, too, that runs off the operating unit, that hooks into the actuator connected to the brake pedal.

When the brakes are applied in the RV, it's going to operate or turn the operating unit on in your towed vehicle, which then, in turn, is going to push air through there and activate that actuator, which it applies and breaks. That way the car is stopping itself. The RV's not having to stop both, and the same thing's going to happen if the car comes separated from the RV, pulls and breakaway switch.Now, as far as the installation goes, it is a fairly straightforward installation, really not that difficult to put in, can be done in your garage. A couple of jack stands to lift the front of your vehicle up. The picture can be intimidating.

Don't be intimidated by it. It's really not that bad.Now that we've gone over some of the features, let me show you how easy it is to get it in. First thing you want to do to is start your installation, is find a place to mount your operating unit. Now there's not a whole lot of places on this vehicle to mount it, so you can see where I put it. It's a pretty open space here.

Two self-tapping screws on this side. The aluminum is a little bit thin here, so what I had to do is drill two holes, put a bolt through it, and then a nut on the inside of the vehicle and then cut the top of that bolt off. Those bolts do not come with your kit. Doesn't matter what sizes you use as long, as it fits through the hole.Next thing you want to do is, you're going to have four wires coming off of it. You're going to have a blue wire, red, brown, and a black wire. Right here is the battery box that goes into the passenger floorboard. On the side of it is a grommet. What I did is, I just ran my brown wire, my red wire, my black wire right through that grommet into the inside of the vehicle.Next thing you want to do is, you want to mount your breakaway switch. I mounted mine right to my bracket that has my 6 pole plug on it. I mounted it right to the top. Because we don't have a whole lot of room here, rather than cut more of this out and add another bracket, I just mounted it to the top. I kind of shaved on the side a little bit. So when they're not using it, they can actually fold it to the side like this, and it stays pretty flush with the front fascia, completely up to you. You can leave it stick out like that, if you like.Next, off of your breakaway switch, you're going to have the blue wire and the black and orange wire. Your blue wire is going to connect to your blue wire coming off your operating unit. So, I just ran that straight back, under the vehicle, to where I have my operating unit mounted. Orange wire, I ran it the same, straight to the back where my operating unit is. Except my orange and black wire, I route it through the grommet where my battery box is.Next, you're going to have a role of airline tube like this in your kit. Even though it tells you in the instructions to install it later, we're going to do it right now, to make it a little bit easier. You want to make sure that the end is cut flat. If you don't do it with just a utility knife, we have airline cutters, physically for these. You're going to use part number F9009. What we're going to do with this, it's going to go right into the side of our operating unit, just like that. We're going to push it in until you can't push anymore. Give it a little tug and make sure it's in.Now, we're going to take that airline tube. We're going to run it right up through the same grommet where we ran all of our wires. So this is my brown wire coming from my operating unit. This is my orange and black wire coming from my breakaway switch. You see I've got them together on one side, put a butt connector on the other end. I have my fuse holder, which is going to be connected to my positive side of my battery, which we'll hook that up a little bit later.My red and black wire I have right here. What I did is, I ran it up along the back firewall, over to the driver's side. Same thing with my airline tube. You can see where it runs up there, and then I ran it across, over to my driver side. You can see my airline tube here, which is going to be connected into my actuator, which I'll explain this and just a little bit. First, I want to show you where all my wires are going.Next, you're going to mount your G-Force box. You're going to have some wires coming off of that. You're going to have a white, red, yellow, green, and black. Now, what I did was, my wiring that is going to my 6 pole plug in the front, which is this wiring here, what you're going to do is, you're going to tie those into that. You can see right here, I tie my colors, green to green, yellow to yellow, white to white. Now with my white, you want to add an extra wire with your white, because it needs to be grounded, and you can see that grounded it right there.Next, you're going to have your red wire and your black wire. In your kit, you're going to have an indicator light, and it's going to mount up on your dash, and you're going to have a black wire and a red wire coming off of it. You're going to take the black wire that's coming off of your G-Force box, and you're going to put it with the black wire that's coming off of your indicator light. You're going to connect those to a butt connector, and put those in a butt connector. On the other side of the butt connector, you're going to take the black wire coming off your operating unit, and that's going to be attached there. Your red wire coming off your operating unit is going to connect to the red wire coming off your G-Force box.Next thing you're going to do is, you need to come down, underneath the vehicle, to the brake booster. You're going to have a one single tube that comes out of your brake booster, like this. It's going to run back to your engine. You're going to have some vacuum line rubber hose in your kit. What we need to do is, we need to tie into this line. Easiest way to do it, there is a clip here, you unclip it, and then along this frame rail, or a side over here, if you unclip it, it's going to give you a lot more room to work.Our rubber hose that we're going to be coming off of this, is going to be going into our operating unit. Now, to make the T, there's two different ways, so make it either for a rubber hose or a rubber line or for a plastic line. I'm going to show you how to make one for a plastic line.It's going to look like this. Now, I haven't put it together, but you can see how I have my rubber hose or my vacuum line cut. This is going to create my T, or my section that I'm going to be cutting out to put inside of this, this line. I have my T fitting that comes in my kit. I cut a little section of hose off. You want to make sure you leave enough, because the hose that's coming out of your brake booster is going to be going into the other end. Another piece of hose here. It's going to go on my other side of my T fitting.Then you're going to have a valve. You want the black side to go toward the engine, so it's going to be going away from the brake booster. We'll go ahead and push these on, like this, looks something like that. You want to take your valve, and you want the yellow end to go towards your T, like that. You're going to take another piece of hose, put it on the black end of your valve, like that. Now we're going to cut out a section here, in this plastic hose, and this is going to fit in this place.Now, before you put your little fitting that you put together, you're going to add two hose clamps like this. Because we have a plastic hose we're connecting to, you want to make sure you put those clamps on, and you just set them on there like that, but this is what's going to hold your rubber hose to your plastic hose. You don't necessarily have to put them on. That's just the way I'd do it. You can always take them all away apart, then we'll go ahead and make our connection.You just got to remember, black side goes away from the booster towards the engine. Sometimes it can be tough to get this hose on this plastic hose. One way to do it, if you take a pair of needle nose pliers and you stick it down inside there and stretch this out a little, that works. Once you do that, spray this plastic hose down with some lubricant, soapy water or something like that, and sometimes you can get that to go on there fairly easy. Other times it can be difficult. So you can see what I did, as I explained.Now that we got that, we're going to take some more of our airline here, or vacuum line, it's going to go into our operating unit, right there, where that knob is, just like that. Now we'll have our plastic panels that we're going to put up, that will cover all of this.Other thing I want to mention is, on your indicator light, you have a black and red wire. The red wire coming off of this . Do you remember the black wire connects to the black wire coming from your G-Force box, and your black wire coming from your operating unit The red wire that's coming off of this, going into the indicator light, actually had to add a little bit of wire to it. What I did is, I ran it through the grommet here out, and I connected it to the blue wire coming off of the breakaway switch.So you see where your white wire's coming to the grommet. I've got it ran down, right down here. I went straight down, underneath the car and connected it to the blue wire that's coming off of our breakaway switch.Now, I didn't connect it up here. I connected it back, by the operating unit. This is what you're going to do, you're going to have to mount your actuator, and it's going to be mounted to some your brake pedal. Now because our brake pedal comes out of the floor, you will need to get part number SM99602. What that does, that bracket extends it up here, so your actuator sits on top.Once you mount it, what you need to do, is you need to mount this bracket to your firewall. It's going to come with a self-tapping screw. Be careful when you go through the firewall right there, because on the other side you have a fluid container, and you want to make sure that you're not going to poke a hole into it. So just make sure you have somebody standing out there watching when you start drilling that hole. You want to have a little bit of play in your wire that's coming out of the back of your actuator.You'll also want, when your brake pedal is depressed, for it to go as close to directly at it as possible. So, however your brake pedal moves, you can see how the back side of this here is going towards that. That means my wire is going to pull my actuator straight back to it.Airline tube that I brought up from my operating unit, ran through the grommet on the passenger side of my battery box, and I route it around. It's connected right here to the top of the actuator, and then insert it. You're going to push it in until it stops. Give it a little tug, to make sure it's in there.Once we test it and everything is working properly, then we can bundle up our wires. Zip tie them. We have some wiring here. We can zip tie everything up here. I'm going to tuck most of this underneath the carpet, just to keep it out of the way and keep it safe. I may run some black electrical tape around my connections here.Now we're going to test it out. G-Force box, and make sure that this knob is loose and pushed all the way to the top. You're going to have an on and off switch. Turn it on. Then we're going to pull the breakaway switch. When I pull the breakaway switch, the actuator should activate our brake pedal.That'll do it for our look at and installation on the SMI Stay-IN-Play DUO proportional supplemental braking system, part number SM99251, on our 2015 Smart ForTwo.


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