Quickly and easily install a 4-way trailer connector on your vehicle with this custom wiring harness. T-One connector plugs directly into existing wiring - no cutting, splicing or tapping required. Call 800-298-8924 to order Tekonsha custom fit vehicle wiring part number 118457 or order online at etrailer.com. Free expert support on all Tekonsha products. Guaranteed Lowest Price and Fastest Shipping for T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector. Custom Fit Vehicle Wiring reviews from real customers.
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Price: $22.49

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

Item # 118457

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Our Price: $22.49

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for 2009 Ford Focus 2Tekonsha
for 2009 Ford Focus 1Tekonsha
for 2009 Ford Focus 3Tekonsha

  • Custom Fit
  • Trailer Hitch Wiring
  • Tekonsha
  • 4 Flat
  • No Converter

Tekonsha Custom Fit Vehicle Wiring - 118457

Quickly and easily install a 4-way trailer connector on your vehicle with this custom wiring harness. T-One connector plugs directly into existing wiring - no cutting, splicing or tapping required.


  • Provides a 4-way flat trailer connector at the back of your vehicle to power your trailer's signal lights
    • Compatible with 5-pole, 6-pole and 7-pole adapters (sold separately)
  • Connects quickly and easily - no cutting or splicing of wires
    • Locate connection points behind tail lights
    • Plug in T-connector
  • Constructed of 16-gauge bonded wire
  • Comes with dust cap for 4-way flat connector


  • Maximum amperage: 7.5 amps per circuit
  • 1-Year limited warranty


This custom-fit T-One connector plugs into your vehicle's wiring harness, which is located behind the driver's-side and passenger's-side tail lights. You will have to remove the tail light assemblies to access this harness.

T-One Connection Location Points Behind Tail Lights

Once installation is complete, the 4-way flat connector will be stowed beneath your vehicle, near the trailer hitch. A mounting bracket (sold separately) is recommended to keep the connector secure.

It is recommended that you use a small amount of grease on all electrical connections - the plugs on your automobile and the 4-pole connector itself - to help prevent corrosion.

118457 Tow Ready T-1 T-Connector - 4 Wire

118457 Installation InstructionsInstallation Details 118457 Installation instructions

This Product Fits The Following Vehicles

2008 - 2011 Ford Focus

2008 - 2011 Ford Focus Coupe and Sedan

Video of T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

Videos are provided As a guide only. Refer To manufacturer
installation instructions And specs For complete information.

Video Transcript for Trailer Wiring Harness Installation - 2009 Ford Focus

Today on our 2009 Ford Focus, we will be installing the Tow Ready T-One Vehicle Wiring Harness with 4-pole flat trailer connector, part number 118457. All right, first thing we need to do on our Ford Focus to install the wiring harness is to open the trunk. Now what we want to do is go ahead and remove the taillight assemblies on both sides of the vehicle. The first step in order to gain access to our taillights is to remove the center trim piece right here. Now with those plastic screws removed, grab one corner of the center piece, pull up on it, and it'll pop off. Go ahead and set it aside.

We can go ahead and remove the panel that covers the left taillight. There are 2 plastic screws on this side, one here and one here. Just go ahead and remove those. Grab the panel at the bottom, and lift up towards the center, pull it out. Once you've pulled it towards the center, go ahead and push it towards the front of the car. Now, with the taillight cover panel removed, we can gain access to the 2 nuts that hold the taillight studs in place.

One's located here and the other one's located here in this hole. Now, using an 11-millimeter socket and ratchet . Now, for the outer one, the stud sticks out a little far on it and it's fairly deep for a deep well socket, so you may need to use a wrench on it to get it started. Using the same 11-millimeter .. Now this one you can actually, since you have access to the stud completely, you can pull the nut off.

The other one we're going to have to let fall down inside the car and take it up once you pull the taillight assembly out. Now grab the taillight on the outer edge and on the inside, wiggle it, and it'll pop loose. There you can here the nut fall down on the inside. Go ahead and pull these and set them aside. Now for the nut that you could not get off because it was recessed inside the hole, the location that it would fall would be right down here. You won't actually have to go looking for it very far.

Now, we'll go ahead and move on to the passenger side of the car and remove the taillight assembly using the same process. Let's go ahead and lay our wiring harness out. The green wire will go to the right side of the vehicle, the passenger side, and the yellow wire will go to the left side, the driver's side. Let's go ahead and set it down on the ground. Come over to our passenger side, we'll take the already removed taillight assembly, and let's go ahead and unplug the bulb, or bulbs, I should say. The bottom one will be your reverse light and this top one here will be your turn signal and brake light. Let's set the taillight assembly in the trunk so it doesn't get damaged. Now I'll just go ahead and start feeding the wires up from the bottom of the car. Okay, that done, let's take the bulb for the taillight turn signal and brake, squeeze here on this connector, and pull the bulb out. Now with the connector and the bulb removed, this is the female end, go ahead and grab the male end of the connector, slide it on in there until it clips into place. Now on the right side of the vehicle, there's also the ground wire, which is the white wire. Use the included self-tapping screw, find a suitable ground location. Right here above the tab where the bumper mounts is a good one. Now, with the ground wire secured, and the connection made to the vehicle wiring harness, we can go ahead and put the taillight assembly back in. First let's put the bulbs back in that we took off. I'm not going to connect this one just yet because it's going to be slightly easier to put the bulb back in the assembly with the connector off. Put it in, turn it, lock in place. Grab the other bulb, do the same thing. Now let's grab the other end of the harness for our tail wires, install it until we hear the click, and then it's in place. Now with all of our connections made, let's go ahead and reinstall the passenger taillight assembly. Make sure we push all the wires down into the bumper cavity as best as we can, and make sure they're not going to come in contact with any of our mounting hardware. Go ahead and put the 2 studs through their respective holes, line up the guide pin here. On the other side there's a little white tab here. Make sure that slides into place with its slot on the taillight. Now, with the taillight assembly back in place, just go ahead and put those 2 nuts back on the studs that they come off of, and tighten them back down. As you can see, with the nuts now tightened back down, the taillight assembly has snugged itself back in in a nice, clean position. With everything done on the passenger side, as far as the wiring goes, let's go ahead and do the driver's side. Pull the assembly down. Let's remove the bulbs, first light on the bottom again. With the bulbs undone, let's go ahead and set the assembly aside in the trunk so it does not get damaged. Now, in order to get the wires up on the driver's side, the easiest way to do that would be to grab something you can pull it up with. I'm just going to use this piece of this air tubing here, so a coat hanger would work, anything of that nature, something that's a little rigid that you can tape the wires to. Just go ahead and route the wire over the crash bar here to the right of it. We'll go ahead and tape our wires to it, and pull it on out. There we go. Just go ahead and remove the tape, set our pull wire aside. Now let's go ahead and make our connection to the vehicle's wiring harness. Grab the male end and plug it into the female end. Now with our connection made to the vehicle, let's go ahead and reinstall our taillight assembly. First let's take the bulb for the taillight, reinstall it on the tail harness until it clicks, insert back into the tail lamp assembly, twist it and lock it into place. Do the same thing for the reverse light. With that done, let's go ahead and reinstall our tail lamp assembly. Let's go ahead and reinstall our nuts on those 2 studs. Now with our taillight assemblies reinstalled, let's go ahead and put all the panels back in the trunk. There's a clip right here and 2 studs here. Go ahead and slide it on into position, line the pins up, and give it a tap back into place. Take your weather stripping and make sure it fits on top of it. I'm just going to grab our plastic pins and screws and reinstall those. There's one there and one here again. Same thing here on the left side. We have the clip and the 2 guide pins, reinstall those. Now we can go ahead and reinstall the center trunk panel. Go ahead and rest it into position, tap it until it clips into place. Let's go ahead and get the weather stripping going back over it so it secures itself properly, and we can get the push pins in. If you don't get the weather stripping on top of this, it doesn't sit back far enough. Let's go ahead and grab our plastic push pin retainers and go ahead and reinstall those. Now with the taillights and the trunk panels back in position, and everything in place and secure, we can go ahead and close the trunk, and continue on with the installation by tidying up the wires underneath the bumper. Now with the excess of wire we have for our trailer harness connector, the easiest way to do this for a clean installation is just for temporary use, go ahead and stick the connector with the dust cap on it, around the safety chain loop on your trailer hitch. Then we can gather up the rest of the wire, pull it nice and tight and zip-tie it to the back of the trailer hitch to secure it. Then we will go ahead and bundle up our excess wire, grab a zip-tie, go ahead and secure our excess nice and tight, and secure the bundle itself. Now with our wires secured to the trailer hitch, let's go ahead and cut off the excess zip-ties just so we don't have to listen to them rattle around anywhere. Now with our wiring all installed, it's a good idea to test everything out and make sure it works before we go hook it to a trailer. Let's go ahead and start with our taillights and running lights, which will be this brown wire here. I just went ahead and grounded to the connector on the harness itself, which is grounded to the body of the car. As you can see there, we've got a good signal. Now let's go ahead and do the left turn signal, which will be the yellow wire here. As you can see that's flashing. Now we'll go ahead and switch over to the right turn signal, which is the green wire, and that's flashing. Now, let's go ahead and do the brakes. Go ahead and step on the brake, please. The green wire there works for the right side brake light, and the yellow wire works for the left side brake light, and that will complete the installation of the Tow Ready T-One Vehicle Wiring Harness for 4-Pole Flat Connector, part number 118457 on our 2009 Ford Focus.

Customer Reviews

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - 118457

Average Customer Rating:  4.8 out of 5 stars   (34 Customer Reviews)

Quickly and easily install a 4-way trailer connector on your vehicle with this custom wiring harness. T-One connector plugs directly into existing wiring - no cutting, splicing or tapping required.
- 118457

by: P.S.03/25/2015

Other than UPS not noticing the apartment number in my address and getting it a day late, very fast delivery. The box was a little damaged but the product was unharmed. I had a friend install it for a case of beer...he's pretty mechanically inclined, so it was not too difficult for him to install. The only thing he had a little issue with was getting the wiring installed. To get the hitch and wiring installed, it took about 1.5 hours, including breaks and not using a lift like a professional shop would have. I bought this so I could update/upgrade my current bike rack to a more stable one, and use a trailer if needed. I don't have the rack yet, and won't be moving for a month or so, but I have a feeling I'll be glad I have the hitch when the time comes. 180764

- 118457

by: garneke06/05/2017

The whole experience was great. Purchased a hitch and wiring harness for my son's ford focus so he could tow a small trailer to support his move to Florida.This turned out to be the most affordable and convenient option available. This installation of all the pieces was simple, the instructions were easy to follow and his trip went without incident. I would highly recommend these products to anyone. 389004

- 118457

by: Stoo08/08/2012

Installation not too difficult, however the wiring is all exposed under the vehicle and not through the trunk as in normal trailer wiring. The exposed receptor wire just hangs down behind the bumper and somehow must be stored so it does not get snagged on anything. Looks bad wrapped around the hitch and all exposed! 50957

- 118457

by: Thomas P10/05/2011

Great product! Installation very simple. Instructions very easy to understand. I had a technical question about possible circuit overloads and the folks @ e trailer were very helpful too. Excellent tracking during shipment as well. I will make this my first stop for any future need. Strongly recommended! 25127

- 118457

by: Kevin09/05/2012

My wife and Installed the hitch in a little over an hour. If fit pretty good. It took a little longer because we did it on the ground. This made it harder to lift into placed. The video from your web site was a great help. I would recommend this product and your company to any do it yourself-fer out there. 53970

- 118457

by: RW05/17/2011

Worked on my 2011 Ford Focus perfectly. I am not an auto guy and installation was super simple and easy. Very little tools and no special ones. Would highly recommend. Using etrailer, this is my 3rd time. Each time has been the same. Easy to shop, right product, shipped on time. 14463

- 118457

by: Jim H.06/05/2012

I installed the Curt hitch and T-One Wiring Harness. Both great products and installed easily. A tip for anyone doing the same on a 2008 Ford Focus, would be to do the wiring harness before the hitch. I put the hitch on first and it was in my way for doing the wiring. 42847

- 118457

by: Tyler W08/26/2012

It's a wiring harness so there's not much to say. The wiring harness was an exact fit to my car. The instructions were clear and accurate. It was easy to install and it works. Exactly what I hoped for. 53063

- 118457

by: Brooks03/16/2011

This is exactly what I needed. Easy, quick, and cheap. The staff got it to me very very quickly and it matched up exactly like I expected it to. Great product at a great price. 9538

- 118457

by: Rob S.09/22/2013

very pleased with product was even able to change the location of the zip ties so i was able to keep the wiring inside the vehicle instead of outside and in the elements. 100965

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by: DAVID A. VON ROEMER06/16/2012


- 118457

by: Bud M.08/05/2012

Access to the connectors was a bit of a hassle but that is Fords problem. Cable was easy to route and the connectors fit perfectly. 50617

- 118457

by: Chris R.08/17/2012

Great customer service and follow up, Recieved product no problems, Highly recommend and I will be using them in the future. 52128

- 118457

by: Pat C.03/22/2013

A quick and proper tie in for hooking up trailer lights after installing a tow hitch. Good quality and no messing around. 72017

- 118457

by: OJR08/15/2016

I've been using this for a year. Works great. I didn't even try installing it myself but my mechanic had no problems. 283910

- 118457

by: Chris D04/18/2017

Trailer hitch and instructions were top notch as was the wiring kit. Would do business again if the need arises. 369209

- 118457

by: Stephen B.02/24/2015

Excellent product prevents the need to cut solder or splice vehicle wiring. Very prompt receipt of the order 175992

- 118457

by: Tom V07/02/2013

Very easy to install. Only wish it could be ran inside trunk rather than stuffed up behind bumper. 87049

- 118457

by: Dwight M.05/01/2015

Went in just as described in the short video. Nice not to splice the wiring together. Thanks. 189335

- 118457

by: Big Al03/09/2011

Order my hitch and recieved it the next day. I am very happy with the product and the service. 8920

- 118457

by: Greg G04/26/2017

Items were packaged well for shipping and installation was without problems. 372875

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by: Dale Heideman05/27/2014

Excellent product, good price, speedy delivery What more could one ask? 132596

- 118457

by: Alan08/14/2011

Instructions were well written, I had no problems installing the wiring. 21845

- 118457

by: Larry02/02/2017

Wiring harness was great, easy fit up, they have it together.!!!! 338074

- 118457

by: Frank B03/10/2017

look real good, I had no problems and the video was a great help 350759

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by: Clinton11/14/2016

Plug and Play. Still works great and was easy to install. 316608

- 118457

by: Chad04/18/2011

Easy to install. Was at my door in less than 5 days. 11901

- 118457

by: Hoyt06/14/2015

Fit easier than I anticipated. Works pe rfectly. 203312

- 118457

by: Dillon07/30/2012

Plugged in and worked great, easy to in stall! 49782

- 118457

by: tom d05/13/2011

easy to use in a difficult situation 13873

- 118457

by: Laert M09/23/2011

Fits perfect on my 2010 Focus SES. 24391

- 118457

by: sean w07/01/2012

good product super easy to instal 46433

- 118457

by: Jeff P07/15/2012

Works great on my 5'x8' trailer 48005

- 118457

by: james johnson04/14/2012

easy install 37178


Ask the Experts about this Tekonsha Custom Fit Vehicle Wiring
Do you have a question about this Custom Fit Vehicle Wiring?

  • Installation Warranty and Transmission Cooler Recommendation for Trailer Hitch on a 2010 Ford Focus
  • The Draw-Tite Class I Frame Trailer Hitch, item # 24805, is bolted to the vehicle frame using existing holes. No drilling or welding is required. All installation hardware to connect the hitch to the vehicle is included. You will need to trim a small amount the heat shield around an attachment hole (see helpful links). The hitch has a towing capacity of 2,000 pounds and a tongue weight capacity of 200 pounds. You will need to check your owners manual for the towing capacities of your...
    view full answer...

  • Trailer Wiring Harness Options for 2007 Ford Focus
  • The Tow Ready # 118457 T-One connector you referenced is not compatible with a 2007 Focus, as the taillight assemblies were a bit different. For the 2007 model, you'd need to hardwire the trailer connector, using part # 18252. The installation is pretty simple. All you'll need to do is use the circuit tester included in the kit to determine which circuit serves which lamps, and tap the green wire into the right turn circuit, yellow wire into the left turn circuit and brown wire into...
    view full answer...

  • Do I Need to Trim My Bumper for Draw-Tite Class 1 Hitch # 24805 to Fit 2009 Ford Focus Coupe
  • I contacted our representative at Draw-Tite to double check and he informed me that The Draw-Tite Class I Frame Trailer Hitch Receiver, part # 24805, does not require any trimming of the lower valence in order to fit. If you have the factory bumper with no dealer add on valence then part # 24805, will fit your vehicle perfectly and will require no trimming of the bumper. Some items you may need to complete your Class I towing setup are listed below. Drawbar, part # 3593 Hitch...
    view full answer...

  • 2008 Ford Focus Turn Signals Blink Faster when Connected to a Trailer with Wiring Harness 118457
  • When the trailer is connected and you use the turn signal, or any of the lights, there is more power draw on the vehicle system and that might be leading to the blinkers going faster. Also check the main ground for the wiring harness # 118457, just to be sure you do not have a developing ground issue. Check the trailer lights to determine how much amperage they draw for each function. Then check to see what the tail lights on the vehicle can handle. You do not want to overdraw the wiring...
    view full answer...

  • Could 2010 Ford Focus Tow Jet Ski Trailer with Curt Hitch
  • As long as the towing capacities of your 2010 Ford Focus (check owners manual) and the Curt hitch part # C11319 don't get exceeded you could tow a jet ski trailer. This hitch has a 2,000 lb trailer weight capacity and 200 lb tongue weight capacity. Typically jet ski trailers are much lighter than that. For a 1-7/8 inch ball mount you would want the part # C45571 or for a 2 inch ball mount part # C45572. For trailer wiring you then would want the part # 118457.
    view full answer...

  • Towing 1000 lb Maximum PWC and Trailer with 2008 Ford Focus
  • The Draw-Tite Class I hitch you referenced, part # 24805 would have a 2000 lb towing and 200 lb tongue weight capacity. Although the hitch would be physically capable of towing your PWC trailer, you will be limited to the capacity of the lowest rated component in the towing system. The decision is ultimately yours, but I cannot personally recommend anything that would contradict the vehicle manufacturer's recommendations. If you decide to tow your PWC, you'd also need the following: Trailer...
    view full answer...

  • Fit of Draw-Tite Class I Trailer Hitch 24805 on 2008 Ford Focus
  • The Draw-Tite Class I hitch you referenced, part # 24805 is a fit for both the coupe and the sedan models of the 2008 Ford Focus. The hitch has a 2000 lb towing/ 200 lb tongue weight capacity (tongue weight is the amount of weight pushing down on the trailer ball). This capacity could be limited by the towing capacity of your Focus, if it's less than 2000 lbs. Check your owner's manual or with your Ford dealer for the towing capacity of your Focus. To complete your towing set-up,...
    view full answer...

  • Will the Tow Ready Custom Wiring Work on a 2010 Ford Focus Without Overloading Tail Light Circuits
  • The T-One Vehicle Wiring Harness with 4 Pole Trailer Connector # 118457 that you referenced would work on your 2010 Ford Focus without overloading the tail light circuitry. Check out the product reviews for this product, there are a number of people who have used this product on Ford Focuses and had it work very well for them. LED lights draw a very minimal amount of amperage when compared to incandescent bulbs, and since the towing lights you would be using are LED you would definitely...
    view full answer...

  • Custom Fit Trailer Wiring Harness for 2007 Ford Focus Hatchback
  • We do have a custom trailer wiring harness that is a fit for your 2007 Ford Focus Hatchback. For that you would want the Hopkins kit part # HM11140495 which is a confirmed fit. The # 118457 only fits the coupes and the sedans though. The taillights are different between the hatchbacks and the sedans/coupes.
    view full answer...

Do you have a question about this Custom Fit Vehicle Wiring?

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Info for this part was:

Expert Research:
Michael H

Expert Research:
Jameson C

Video by:
Joshua S

Video Edited:
Jacob T

Test Fit:
Rick A

Video Edited:
Andrew L

Updated by:
Laura H

Video by:
Dustin K

Updated by:
Sarah W

Test Fit:
Brent H

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