Trailer Wiring Harness Installation - 2012 GMC Terrain

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How to Install a Trailer Wiring Harness on a 2012 GMC Terrain

Speaker 1: Today on our 2012 GMC Terrain, we're gonna be taking a look at and showing you how to install the Tekonsha T1 vehicle wiring harness for factory tow package with a four pole flat trailer connector, and that's gonna be part number 118264. Our wiring harness is designed to stay on the inside of the car until we're ready to use it. And once we do, we can lift up the compartment for our spare tire, bring our four pole wiring out, and so long as we keep it within the area on this weather stripping here and away from the latch, that weather stripping should have enough give to where it won't damage the wire. We can simply close our hatch and we'll hook up to our trailer. Now it is gonna provide us with a four pole flat trailer connector and all the required lights to get down the road safely, like our taillights, turn signals, and our brake lights.It's also gonna have an integrated dust cover that's gonna keep all the dirt and moisture and debris out of it whenever we're not towing. And then once we're done towing and we wanna store our wire, we can just bundle it up, keep it right by our spare tire.

Now as far as the installation goes, it's gonna be extremely easy. We're just gonna have one connection point to make to our factory connector, and it's gonna provide us all the signals we need. Now that we've seen the end result of our wiring harness, let's show you how to get it installed. To begin our installation, you're gonna wanna open up the rear hatch on your Terrain, and we already pulled our wiring harness out of the package, and we're gonna be looking for a connector that's gonna match up to the one on our harness. So we're gonna lift up the floor covering here, just kinda slide it out of the way, and if we come to the driver's side in the very back corner here and we look in through that panel, we'll see that there's gonna be that connector that it'll match up with.Now we have a couple of different options of how we're gonna access it.

You can either try to feed your harness in from the outside and make the connection, but it is rather far in there, so what we can also do is take a large screwdriver or trim panel tool and remove the connector from the body. There's gonna be a small plastic clip that's holding it in place. You just wanna pry it away, and then we can pull that connector out, and make the connection a lot easier. We just try the connector off and reach in, grab the connector itself, and bring it towards the outside. That'll make it a lot easier to make that connection.

Then we can just match up our plugs, make sure they lock into place, and just tuck that connector back in the corner, and we're gonna keep our four pole wiring underneath by our spare here until we're ready to use it. However, before we put everything back, we're gonna go ahead and test our wires to make sure that everything is working properly.So I'm gonna plug in my four pole tester, and if you need one of these you can pick one up here at using part number I26. So I'll go ahead and run through my lights and verify that they're all working properly. So with my headlights on, we can see that the taillights are working, along with the left turn signal, right turn signal, and our brakes. Now all we have left to do is hook up to our trailer and hit the road.

And that'll finish up your look at the Tekonsha T1 vehicle wiring harness for factory tow package with a four pole flat trailer connector, part number 118264 on our 2012 GMC Terrain.

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