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Curt T-Connector Vehicle Wiring Harness Installation - 2021 Subaru Outback Wagon

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How to Install the Curt T-Connector Vehicle Wiring Harness on a 2021 Subaru Outback Wagon


Ryan: Hey everybody, my name's Ryan and here at etrailer, we install, test, fit and review a lot of different parts. That way we can help answer any questions those of you might have. And that's exactly what we're doing here today on our 2021 Subaru Outback Wagon. We're going to be taking a look at it and showing you how to install the CURT vehicle wiring harness.I know when I'm going down the road, I personally see these Subaru's doing a little bit of everything, which does include pulling some trailers. So if that's your case, you're definitely going to want a way to eliminate the lights. That way you're not only safe, but legal as well.

And one thing too a lot of people don't think about is a lot of these newer accessories actually have lights on them. So a cargo carrier, perfect example. If you have one of those accessories, you would like to use it I'm sure. And having this trailer wiring is also going to give you the ability to light up them as well.So it's pretty cool about this wiring is you can mount it in different locations. So you can have it mounted up like you traditionally would see next to your hitch here on the outside if you use your wiring a lot, or you can keep it stored on the inside, out of sight and out of the elements.

And that's exactly what our customer has chosen to do today. If that's how you choose to mount it, then it's going to be super easy to use, really not an inconvenience. If you want to mount it on the outside, I'll show you how to do that as well during our installation video.With that being said, just going to open up your cargo compartment there, grab your wiring and just drape it over your bumper here. Anywhere along the threshold is fine where there's rubber stripping. You just don't want to get it hung up on the latch.

And you're just going to close your hatch on it. Now, that may seem a little odd smashing the wiring between there like that. But because of that weather stripping, it's not going to be pinched or anything so you can see how I can still move it around. Not going to have to worry about damaging it like that.But it's going to give us plenty of length. So we know we shouldn't have any issues at all hooking up to our trailer or our accessory.

And it's also going to come with a nice rubber dust cap to help keep out any moisture, dirt and debris, things like that. I would suggest from time to time applying some dielectric grease to the terminals, especially for those of you mounting it to the outside of your vehicle. That's really going to help ensure that everything stays in good shape.I will say CURT has came a long way with their construction quality. Everything feels really well built. The connector isn't fluency or anything like that. It really feels good in your hand. So it should last for years to come. So at the end of the day, a great way to be able to power up your trailer lights or even your light up accessories.Now, as far as installation goes, it's pretty easy, more or less just open up a few panels and plug it right in. Now, if you've installed lighting on your Subaru in the past, maybe a little older model, this one is going to be a little bit different. The connector plug is in a different location, but honestly it's almost easier to get to. So you shouldn't really have any issues at all. I'll show you where it is and how to plug it in. Speaking of which, let's go ahead and do that together now.So to begin our installation, we're going to be here at the back of our Subaru and we're going to need to locate the factory connector plug, that's going to be inside. So we'll open up the hatch and then what we can do is remove some of our floor coverings. So we need to take out this one here in the center. We'll lift to open. Pull out. We're going to take this one off here on the passenger side. Again, it just pulls up and we're also going to grab the center foam piece and set this off to the side as well.So now what we need to do is on the passenger side, we need to remove this foam piece. It's going to be two fasteners that look just like this. These are plastic. And to get them out, can use a trim panel tool or a flat-head screwdriver to get underneath the head of it. And you're going to want to pry up. And I've noticed in the past, these do break pretty easily. And one thing you can do to avoid that is if you take your thumb and just put a little bit of downward pressure on the fastener as you're prying up. So that'll allow it to pop out without breaking. The other one is located just up a little ways.So once you have it removed, you grab her foam, and work it out and set it off to the side. So now we're able to locate our factory connector plug. So we're on the passenger side, right where you remove that foam piece. You can see it right here. So that's what we're looking for. It is taped up. So I'm going to do to get us some more room to work. Just very carefully cut that pink tape. That'll allow us to pull it out, making it easier to work with. And now that we located this, we can grab our new harness and get everything plugged in.So now when I went ahead and did is grabbed our new wiring harness, and this end is simply just going to plug right into that factory connector there. Now we can do is take our white wire with the pre-attached ring terminal. This going to need to get grounded to the body of our vehicle. So I'm just going to go right here on this flat area of sheet metal and take the included self-tapping screw and get it secured down.Now we can do this. Come to your fuse holder, take the included fuse, push it in, close up the dust cap. And now before we get too carried away, securing our wiring and putting everything back. What I'm going to do is grab our 4-Way flat connector plug in a tester, which you can find this one here at etrailer. That way we can check our wiring to make sure that it is all working properly.So I'll go ahead and try out our left turn signal, our right turn signal, our brakes and finally our running lights. So now that we know the wiring works, let's go ahead and secure everything. I'm going to secure the box using the included two sided sticky tape. So just going to peel off one layer, make sure the box is nice and clean. Stick it to it, peel off that other layer of backing paper like so. And I'm going to put it right back here in this corner where it's flat and out of the way. Want you want to do is make sure that surfaces clean too. You just use some rubbing alcohol or something like that. We'll tuck that back there and stick it to the body of our vehicle.Now, what I went ahead and did is just use a couple of zip ties to help tidy up and secure our wiring along this edge. So when it comes to routing your 4-Way flat connector, you got a couple of different options. You can keep this stored on the inside of your vehicle, like our customer's chosen to do today. But if you'd rather this be permanently mounted next to your hitch, outside of the vehicle, can also do that too. So the way you would do that. So if you loosen up your spare tire and hold it up. You can see that there's actually a grommet right there, rubber grommet. And if you pull that out, it goes right down to the bottom side of our vehicle.So take your wiring, push it through and drop it down that way. I would suggest cutting a small slit into the rubber grommet. That way you feed your wiring through there. You're not going to have to worry about the metal cutting it up or rubbing up against it. And I would also suggest getting some RTV silicone which you can get here at etrailer, and just putting some silicone over that slit and the rubber grommet. That way you don't have to worry about any fumes or moisture getting through to the inside of your vehicle.At this point, we can go ahead and start to reassemble all of our interior panels. Take your foam piece, line that back up and simply just re-install our push pin fasteners. From there, we're going to start to set everything else back into place. When you set this in, what I like to do is take our 4-Way connector, if you're keeping it on the inside, just route it up into that storage compartment. It makes for a great storage place and her panels. We'll just get a pop right back into position. And that'll finish up our look at and our installation of the CURT vehicle wiring harness on our 2021 Subaru Outback Wagon.


Questions and Comments about this Video

Martin M.

I have this harness in my vehicle and it has killed my battery, forcing me to replace it twice since I purchased it. I only recently noticed that the harness was the issue.. It was drawing power not sure if this a defective harness or if that is how harness works. I would like some feedback please if possible. Thank you.

Etrailer Expert
Reply from Victoria B.

The only thing to really check would be the ground wire - making sure it is installed securely to a bare, clean metal spot on your vehicle. If your ground is secure, then I would lean toward an issue with the converter box that may be covered under warranty. You can reach out to our Customer Service team if you think it would be a warranty claim.

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