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

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

Item # 118405
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Custom Fit Vehicle Wiring

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T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector 4 Flat 118405
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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. Powered ModuLite reduces strain on wiring system. Call 800-298-8924 to order Tekonsha custom fit vehicle wiring part number 118405 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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Tekonsha Custom Fit Vehicle Wiring - 118405

  • Custom Fit
  • Trailer Hitch Wiring
  • Tekonsha
  • 4 Flat
  • Powered Converter

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. Powered ModuLite reduces strain on wiring system.


Features:

  • 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
    • Locate connection points in rear cargo area
    • Plug in T-connector
    • Run hot lead to car battery
  • Includes ModuLite to ensure that your vehicle's wiring matches that of your trailer
    • Powered module connects directly to battery to avoid overloading vehicle's electrical system
  • Constructed of 16-gauge bonded wire
  • Comes with dust cap for 4-way flat connector


Specs:

  • Maximum amperage:
    • Stop/turn lights: 2.1 amps per circuit
    • Tail lights: 4.2 amps per circuit
  • 1-Year limited warranty


Installation

This custom-fit T-One connector plugs into your vehicle's wiring harness, which is located inside your trunk or cargo space, behind the tail lights on both the driver's side and passenger's side. You will need to remove some interior trim or carpeting to access this harness. Once you've plugged in the T-connector, run the hot lead up to your car battery. Connect the lead to the included fuse holder, and then connect the fuse holder to the positive terminal on your battery and insert the provided fuse.


Once installation is complete, the 4-way flat connector will be stowed within your trunk or rear cargo area.


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.


ModuLite Powered Tail Light Converter

A ModuLite power module is built into this T-One connector. Because most trailers run on a two-wire system - wherein the brake and turn signals are carried on one wire - the separate brake and turn signals from your vehicle's three-wire system need to be combined so they are compatible with the wiring system of your trailer. This power module functions as a tail light converter to combine the brake and turn signal functions of your automobile so that they run on one wire to properly activate your trailer's tail lights. Note: This will not affect how the tail lights on your vehicle operate.


With a ModuLite, your trailer's lights will be powered without overloading your vehicle's electrical system. Because the module draws power directly from your car's battery and bypasses the electrical routes that are used by a basic wiring harness, there is virtually no draw on your tail light circuits.



118405 Tow Ready T-1 T-Connector - 4 Wire - Modu-Lite

Installation Details 118405 Installation instructions

This Product Fits The Following Vehicles



California residents: click here


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 - 2016 Toyota Corolla

Speaker 1: Today on our 2016 Toyota Corolla we're going to be taking a look at, and showing you how to install the Tekonsha T-One vehicle wiring harness for 4-pole flat trailer connectors, part number 118405. This is everything that's going to come in our kit. This is everything you're going to need to get your wiring installed and get your power to either your trailer or cargo box with lights on it that you're going to have on your hitch. You're going to have your 4-pole connector, you're going to have your converter box, which is going to push power to your lights. It's going to connect directly to your battery. These are going to connect to your tail lights on your passenger and driver's side.

You're going to have your fuse with your connectors, and you're going to have your wiring that goes to your battery. Now your converter box here, that's going to give your trailer lights power without pulling power from your vehicle lights. It's going to come directly from the battery. It's also going to protect your vehicle from back feed from the trailer lights, or trailer wiring if there is any problem with the wiring itself.This is what our wiring harness looks like when it's installed on the vehicle, and you can see it's going to live inside the trunk space. When it's not in use you can just roll it up, tuck it over in the corner, and when you're ready to use it, you're just going to take it, hang it outside however much you need, coming over top of this rubber seal here.

It's not going to damage your wire, but you want to make sure you stay away from this. So, you're just going to pick out however much you need, close your trunk into place, hook up your trailer and you're ready to go.First thing we need to do is we need to remove our trunk coverings here. We're just going to roll this up and set it aside, and then remove our liner. We're going to have to take out our kick panel here, our threshold. We're going to take a flathead screw driver and we're going to do that same thing on the other side.

Next thing I do to remove this, we're just going to pull up on it, and these little tabs will pop up. The next thing we want to do is we want to gain access to the backside of our tail lights, so we're going to have to take out these here, we're just going to kind pull this back. Again, the flathead screwdriver.The next thing we're going to do is over here on our driver's side, behind our driver's side taillight, we're going to have two connection points, where we're going to have four connectors. As you can see, they're going to be different sizes. All we need to do is we're going to match up the plug to the ones we take off.

We'll start with this bottom one here, inaudible 00:03:19 at the top, and all we're doing is we're pushing down to remove them. As you can see our taillight plugs, we have three and a two. We have a three and a two. Now we're just going to take these and replace the ones we just took off. Take our three, plug it into the spot with the three, we're going to take our two, plug it into the spot with the two.Next what we're going to do is we're going to take the ones we took out and we're going to plug them into the ends of these. Again, two matches with the two, three matches to three. Next what we're going to do is we're going to mount our converter box and we're going to take some alcohol, we're just going to rub the back of that, and then I think we're going to put it right her. We're just going to rub that and make sure we have good clean surfaces. In our included kit we're going to have two-sided tape. Peel off one side, stick it on there, firmly press it into place. Next we'll peel off the back side underneath this wire here, get a good place to put it. We'll go ahead and again press it firmly into place. Make sure you've got it good and solid on there.Now we'll go ahead and install our ground. What we want to look for in any factory ground point that we can hook that to. That will just help keep us from having to drill in. This spot here with the nut on it, we're going to go ahead and put it there. We're going to use a 10 millimeter socket. We'll go ahead and put our ground into place there, replace our nut, and then we want to tighten it down just enough so our ground wire doesn't move. The next thing we're going to do is we're going to take our 12 gauge wire and we're going to connect it to the end of our red wire here. That's going to give us our power from our battery. Go ahead and strip it back. We're going to use one of the included butt connectors, crimp it down, make sure you have a good solid hold on in, and what I like to do is go ahead and wrap it with some electrical tape. What I'm going to do is with all of our extra . our wiring that's right here, I'm going to go ahead and zip tie it to this factory wiring just to keep it all together and to make sure we're not going to pull on our converter box here.From here what I'm going to to is I'm going to go ahead and route my green wire over to my passenger's side. What I'm going to do is I'm going to zip tie it right to this factory wiring that runs right over to that side there, like that. Another thing that I noticed is I'm worried about these possibly rattling around, maybe hitting the side, so I'm going to go ahead and zip time these up also, just in case. On our passenger's side we're going to have two prong, but you're going to have two different plugs. If you remember on the driver's side, the bottom one was a three prong and the top one was a two. We're going to plug the two into one end, and plug the there end back into the taillight, like that. Then we're going to take our extra wiring that we have here, we're just going to bundle it up and then we'll just zip tie it right to the existing wiring.Once we get all of our wiring in place we can go ahead and replace our covering here, push the inaudible 00:08:01 back in place. Next what we're going to do is we'll take our power wire, and I'm going to zip tie it along the same wiring that I zip tied our green wire on, only I'm going to stop right here at the center of the vehicle. The next thing we'll want to do is we're going to remove our spare tire. The reason why we only went to the center for our power wire is we're going to put a little slit in one of these grommets and we're going to run our power wire right down through. Once we get our wiring, you want to make sure you leave a little bit so we can put our spare tire back in. This particular application, this 4-pole is going to live inside the vehicle and only be pulled out when it's used through the trunk. Now, if you wanted to route this outside of the vehicle where it stays outside the vehicle, you can route it the same place I rerouted the power wire, through that grommet. You just have to cut a little bit bigger hole to feed both of them through.Next we'll go ahead and put our threshold back in place. We're just going to push down on it. You can see here this is where we ran our power wire. It's a good idea to take some silicone and just put it around the edge of the wire where the hole is, just to kind of help keep some moisture or anything like that from getting inside of your trunk.Now I'm going to show you how I ran it up to the front of the vehicle. Make sure you know what side of the car your battery's on. This car, it's the driver's side. What we did is we ran it from our grommet here, I went over top of this box, and hat I like to do is try to find some factory wiring and as you can see I zip tied here, I went over top of the gas tank hose, I zip tied here. Another thing to note is to make sure when you're zip tying and you're pulling your wire through you stay away from any moving parts. I came back over, zip tied here, down to these slides here that run all the way up to the front. Now, what I did is I ran a line from the top, close to my battery, away from moving parts and away from anything that's heated. I ran . I just had some airline hose laying around, I ran it down to give me a path. What I did was I took my power wire and I fed it up through my line here.Now what we're going to do is we're going to go back up top we're going to take our airline tube and pull it up through, and it's going to lead our power wire up to the top side. Now that we have our power wire pulled up I can go ahead and route it and make sure we're going to have enough to get to our positive side of our battery. What I'm doing is I'm just trying to see if I can, without having to cut a bunch of it off, if I can do it this way. Now that I have routed my wire around, I'm going to go ahead and throw a couple of zip ties on just to hold it in place.Now that we've run our wire, what we're going to do is we're going to strip back some coating on that, then we're going to take our fuse holder and we're going to cut it in half. We're going to strip back both sides and take our butt connector included in our kit, connect it on one end, and on our other side we're going to connect our ring terminal that's included in our kit. Now, what I'm going to do is I'm going to go ahead and take some electrical tape and put it around the end of this side of the ring terminal. Next what we're going to do is we're going to take the other end of our butt connector and we're going to connect it onto our power wire that we ran from the back. Now that we have that connection made we can go ahead and hook up to our positive side of our battery.Now that we have our wires connected, let's go ahead and test it out using part number I26. Running lights, left blinker, right blinker, brake.That will do it for the Tekonsha T-One vehicle wiring harness with 4-pole flat trailer connector, part number 118405 on our 2016 Toyota Corolla.


Customer Reviews

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - 118405

Average Customer Rating:  4.7 out of 5 stars   (122 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. Powered ModuLite reduces strain on wiring system.

- 118405
by:

Great product at a fair price. Easy ins tall. 686702



- 118405
by:
2007 Toyota FJ Cruiser

Easy install, great price, awesome product quality 637804



- 118405
by:

Installed as advertised, fit as advertised and looks like it was custom built for the car (2015 Camry). A very good looking hitch assembly that blends in beautifully and looks like it belongs there. Installation videos are a real time and effort saver. The hitch receiver is a slightly loose for my taste but otherwise I am extremely pleased with it. 689994



- 118405
by:

This is a fantastic, high-quality wiring setup. Tekonsha makes good stuff, and eTrailer sells good stuff. Easy, straightforward install, good instructions. 704336



- 118405
by:
2015 Toyota Camry

It fit my car. Installation directions are understandable and all parts needed were present. I work on my cars a lot so for me everything fit and was easy. It seems to hold up well and is strong. 366897



- 118405
by:

Easy wire hookup. Running the wire to the battery under the vehicle took the most time. You'll need extra wire ties to make sure the wire doesn't sag. Instruction said to run the wire through a grommet in the storage compartment. This will not work if you have dual exhaust. Ran the wire through a grommet just behind the back seat. 12672



- 118405
by:
Mazda

This wiring kit was purchased for installation on a 2017 Mazda 3 sedan. As received, the installation instructions made no reference to any Mazda 3. There was reference to a Mazda 6 with incomplete instructions and pictures. The company web site offered no further clarification. I am an automotive engineer with an electrical background and the installation was far from obvious. Wire color codes did not match the car harness. The power wire to be routed to the battery was black. Vehicle power is usually red. The fuse holder and its wiring to be atttached to battery plus was yellow. The power wire leading into the control module was red. So, we have a yellow wire connected to a black wire, connected to a red wire. What a mish-mash! I finally called the manufacturer and spoke with a customer service representative. He was not able to help immediately but took time to find the right information and called back. Once the install information was received, the installation went reasonably well with the most difficult part being the routing of the power wire forward to the battery. To protect the wire and install it securely, I removed the plastic undertrays and routed the wire alongside some fuel or hydraulic lines. As mentioned by other users, more ty-wraps would have been useful. I used some from my existing supply. After install, I tested the function with the boat trailer and it appears to work as designed. 451619



- 118405
by:
Toyota FJ Cruiser

The wiring harness was delivered to my front door within two business days. I installed the harness in my FJ and it works perfectly. You will need two tools to complete the job, they cost me $40. bucks but the net cost was still well below a dealer install. You will need long needle nose pliers, I bought 8 inchers. Also, you will need a tool to pop out the retaining fasteners on the trim; if you try to use a screwdriver you will most certainly break the fasteners. You will also need a wire stripper tool to complete the job. I am not the sharpest knife in the drawer so the job took about 2 hours to install and reassemble the trim. I would recommend this product to anyone who can read and follow directions. Thanks much to etrailer for a great value and fine product. 59796



- 118405
by:
2017 Toyota Corolla

I ordered the wiring kit and after receiving it I realized that on the box it would fit up to a 2016 Toyota Corolla. Mine was a 2017 so I decided to go ahead with the install. When I got to the installations instructions my Corolla was not listed anywhere. It only listed the Toyota FJ Cruiser, Mazda 6 Sedan, Mazda CX-7 and Toyota Camry. I have installed several wiring kits in the past so I decided to try it without the instructions. I was able to do so by using the Camry instructions but it would have been accomplished faster had the correct instructions been in the box. I also wonder how easy it would have been for a first time installer ? I rated it with one star due to the incorrect instructions but would give it a 5 star rating for the quality of the wiring harness. 404212



- 118405
by:

Love love love this company!! Saved like $300 buying it here and doing install myself. The site is amazing and gives you the videos for both the hitch and wiring install and it’s super easy. Thank you for providing us a cheaper alternative than getting ripped off by local trailer hitch install places . You’re the best 737483



- 118405
by:

Quality product, excellent service. 726622



- 118405
by:

Upon rwceiving this product it was faulty (no fault of etrailer it was just a bad unit). Etrailer was above and beyond reaponcive and sent a replacment unit rite away. Since installation there have been no issues. I have and will continue to utalize etrailer for all my trailering needs. 725037



- 118405
by:

Good product, easy to install, included all hardware. Thanks! 722747



- 118405
by:

Easy to install wiring kit, and I'm not that handy of a guy! 721847



- 118405
by:

this hitch fit perfectly, the wiring kit was awesome too. The etrailer [online video website] video on the wiring kit install was very good. Whole project was complete in about an hour. 717219



- 118405
by:

Arrived quickly, relatively easy installation, worked first time. 715377



- 118405
by:
2016 Toyota Camry

Another solid hitch receiver from etrailer. Service was fast and it arrived quickly. This is the fourth hitch receiver I have bought from etrailer because of the great quality, excellent service and fair prices. 714947



- 118405
by:

Did the install myself and had no problems. Everything works great! 711729



- 118405
by:
2016 Toyota Corolla

Great service and fast delivery! Installation of trailer hitch and wire harnesses was simple. Took less then 2 hours and all I did was put the rear of my 2016 Corolla S on jack stands. Tools needed not included in kit. Good pocket knife, wire stripper and wire cutters, a ratchet set up to 19mm. Screwdriver and electrical tape. Also some good cleaning solution such as alcohol. 704219



- 118405
by:

The trailer hitch arrived in good shape. I have not installed the hitch yet. Hopefully it fits. Thanks 703538



- 118405
by:
2017 Toyota Camry

All equipment was delivered on time. Hitch, wiring harness, receiver and ball. Watched video's on installation of harness and hitch. Went down to my garage and installed both with the help of my girlfriend. Very satisfied with the products and the installation. etrailer supplied the goods and the knowledge. I am very happy that I went this route. 697171



- 118405
by:
2014 Toyota Camry

Great product. This is my fourth one from etrailer. A bit more difficult to install. Had to think up some way to hold it up singlehandedly, but managed it. See attached picture. Will deal again with you in a flash. 695538



- 118405
by:

Good product line. Bought trailer hitch, etc. A few years ago. Traded cars. Bought more stuff recently. Complete product line. Good website. Instant service. 679843



- 118405
by:

Harness Light Kit install went well with no problems and it only took like 1hr...! 660727



- 118405
by:
2007 Toyota FJ Cruiser

easy to hook up,works great thank you 655632


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Ask the Experts about this Tekonsha Custom Fit Vehicle Wiring

  • Trailer Wiring Recommendation for 2018 Mazda 3
    The two harnesses you mentioned are made by two different companies which have different fit lists for the 2018 Mazda 3. The part # 118405 has been confirmed as a fit for the Sedan models but not hatchback whereas the Hopkins kit part # HM11141824 fits all models of the 2018 Mazda 3. It's also the only custom fit option that does this so it would be your best option.
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  • Parts Needed to Install a 7-Way Trailer Connector and Brake Controller on a 2010 Toyota FJ Cruiser
    The 4 to 7-Way Adapter, # 37185, is included in the Brake Controller Install Kit, # ETBC7. If you have a 2010 Toyota FJ Cruiser with the factory 4-way trailer connector, then you will only need a brake controller, like the Prodigy P2, # 90885, and the installation kit # ETBC7. The brake controller install kit has everything you need to complete the installation other than the brake controller. If your FJ Cruiser does not have a factory 4-way trailer connector, then you will need to...
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  • Best Way to Add 7-Way Connector on 2009 Toyota FJ Cruiser for 12V Power to Trailer
    The best solution for your application is to install the Tekonsha T-One # 118405 on your 2009 Toyota FJ Cruiser for your standard trailer lights and then add the Wiring Kit # ETBC7L which comes with everything you need to convert the 4-Way to a 4-Way/7-Way and add the 12V function. Please note that as power runs along that line there will be some voltage drop which will likely keep your batteries from charging completely. To help remedy this I recommend using the Redarc In-Vehicle BCDC...
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  • Installing Brake Controller and 7-Way on 2007 Toyota FJ Cruiser with Tow Package
    From your description, I'm assuming your FJ Cruiser has the factory equipped 4 pole trailer connector. To install a controller on your vehicle, you'd need our Brake Controller Installation Kit, part # ETBC7. You'll also need to choose a brake controller. I can highly recommend the Tekonsha Prodigy P2, part # 90885. The install kit includes everything needed to install a brake controller, including the adapter needed to convert the existing 4-pole to a 7way trailer connector. All wire,...
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  • Brake Controller and Install Wiring Recommendation for 2010 Toyota FJ Cruiser
    You will need to start with a 4-way (if you do not have one). For that you would want the # 118405. From there you would need to convert the 4-way to a 7-way so that you can install the brake controller. For that you will want the Brake Controller Install Kit and 7-Way Adapter part # ETBC7. I attached installation instructions and an install video for this product as well. For a brake controller I would recommend the Prodigy P2 Brake Controller part # 90885. This is our best selling...
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  • Adaping 4-Pole Connector to 7-Way on 2010 Toyota FJ Cruiser
    If the trailer you are planning on towing does not have electric brakes and you simply need to provide a lighting connection for the trailer, you can very easily convert your existing 4-pole to a 7-way by using a 4 to 7-Way Adapter, part # 37185. If the trailer has electric brakes, you will need a brake controller to actuate them. I would recommend the Tekonsha P2, part # 90885. The P2 is very user friendly and the initial set up is simple. You will need the Brake Controller Install...
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  • Recommended 4-Way Flat Connector for a 2014 Toyota FJ Cruiser
    I do have a solution for you to add a 4-Way Flat wiring connector to your 2014 Toyota FJ Cruiser but unfortunately the T-One Vehicle Wiring Harness # 118245 won't fit. Instead what you will need to use is one that tees in behind the tail light housing. I recommend the T-One # 118405 because we have found the Tekonsha wiring to be the most reliable. This tees in behind your tail lights and then draws power directly from your battery so as not to overload your wiring system. Attached...
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  • 2012 FJ Cruiser 4-Way Trailer Wiring Recommendation
    For 4-way trailer wiring for your 2012 Toyota FJ Cruiser you would want the part # 118405 that has been confirmed as a fit for your vehicle. The wiring harness you found could be for trailer wiring but it is not a style of connection that we sell a harness for. There might be a Toyota option that you could get through a dealer. The part # 118405 installs inline with the taillight assemblies of your vehicle to provide the 4-way signal. I attached an install video for you to check out.
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  • How Do I Set up a 2008 Toyota FJ Cruiser with a 7-Way and a Brake Controller
    I am not aware of a conversion kit that would be necessary for your FJ Cruiser. All you should need is the appropriate brake controller, I recommend the Tekonsha Prodigy P2 part # 90885, and the install kit, part # ETBC7. If your vehicle does not already have a 4 way trailer connector, you will need a T-1 Harness, part # 118405, the one you were looking at. The T-1 connector would tap into your lighting circuits to provide lighting for your trailer. We also have a very good two...
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  • How To Tell If Lights On 2015 Mazda 3 Are LED Or Incandescent
    You can find out if you have LEDs a couple of ways. The easiest is to remove the lens of the lights and if it has a bulb it is incandescent. If it has diodes then it is LED. Another way is to turn the lights on and then watch as you turn them off. If the light go off abruptly, they are probably LED. If the filament takes a moment to go out then it is probably a bulb. The third way is to contact your dealer with the VIN and they will be able to tell you what lights are on your Mazda 3.
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  • Trailer Wiring Harness Recommendation for 2014 Mazda 3 Hatchback
    For your 2014 Mazda 3 Hatchback without LED taillights the Tekonsha wiring kit part # 118405 would be the correct we recommend. I attached a link to an install video that shows the harness installed on a similar Mazda vehicle as well as a link to the install instructions for you to check out as well.
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  • Trailer Wiring Fit Recommendation for 2017 Toyota Camry
    For trailer wiring confirmed as a fit for your 2017 Toyota Camry you would want the Tekonsha kit part # 118405. We do carry this and it will work well.
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  • Trailer Wiring Harness Recommendation for 2014 Mazda 3
    The good news is that the trailer wiring harness part # 118405 fits your 2014 Mazda 3 whether it has LEDs or does not so it would work well for you either way. It also fits sedans or hatchbacks too. LED taillights are a bit different than incandescent bulbs. For me, if they are obnoxiously bright and almost hurt your eyes to look at they're LEDs...haha. The other more reliable way to tell is to look at the transition of the lights from off to on. If they lights seemingly warm up as they...
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  • Right Side Trailer Lights Not Working on Trailer Towed by a 2011 Mazda CX-7
    This sounds like a bad ground problem if it is just the one side. The first thing you should do is unplug the trailer and use a circuit tester like # PTW2979 if needed to test the 4-Way on the vehicle. If all of the functions are working fine on the 4-Way then you know the problem is somewhere on the trailer. If the 4-Way is not functioning correctly then test the wires going into the converter box from the vehicle. If they are not correct then the problem is on the vehicle and will...
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  • Recommended Trailer Wiring Harness for 2019 Toyota Corolla Sedan
    For your 2019 Toyota Corolla I highly recommend the Tekonsha T-One Vehicle Wiring Harness # 118405. We have found over the years that Tekonsha's powered converter modules are extremely reliable and hold up much better over time than those from other manufacturers. This particular harness will plug right into existing ports behind the tail lights on your Corolla and it includes the hot lead that needs to be run up to the battery. This will provide you with a 4-Way connector to connect...
    view full answer...
  • Converting a 4 Pole Connector on a 2012 Toyota FJ Cruiser to a 5 Pole Boat Trailer Connector
    Usually when you have a boat trailer with a 5 pole connector the trailer has hydraulic surge brakes and not electric brakes and you would not use a brake controller. The additional blue wire is for a reverse lockout on your hydraulic surge brakes to deactivate them while the tow vehicle is in reverse. If your boat trailer is the only trailer you plan on towing then you will want to install the T-One Vehicle Wiring Harness with 4 pole trailer connector, part # 118405, and you will want...
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  • Where Are Vehicle Connectors For Trailer Harness Wiring On 2014 Mazda 3 Sedan
    The connection points for the T-Connector Wiring Harness, part # 118405 are located behind the driver and passenger side tail lights - inside trunk. The 4-way trailer connector will hang out of the trunk area on your Mazda when you need to use it. When it is not being used you can place it inside the truck and possibly under the carpet in the trunk. It will not affect the vehicle's lights if installed correctly.
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  • Recommended Trailer Wiring Harness for 2006 Mazdaspeed 6 Sedan
    Yes, the Tekonsha T-One Vehicle Wiring Harness # 118405 referenced in your question is confirmed to fit both the 2006 Mazda 6 and the Mazdaspeed 6 Sedan. I confirmed this with my contact at Tekonsha. This custom-fit harness will install by connecting directly to the built-in ports behind the driver and passenger side tail lights (inside the trunk). You will then need to run the hot lead up to the vehicle's battery. I have attached the complete installation instructions that you can...
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  • Recommended Trailer Wiring Harness for 2018 Mazda 3 with LED Lights
    For your 2018 Mazda 3 Sedan with LED lights, I recommend the Tekonsha T-One Vehicle Wiring Harness # 118405. This custom harness is confirmed to fit your vehicle and will install by connecting directly to existing ports located behind the driver and passenger side tail lights (inside the trunk). Once these connections are made, you will just need to run the hot lead up to the Mazda's battery. This will provide you with a 4-Way connector to connect with and power a trailer's basic signal...
    view full answer...
  • Where are the 2008 Toyota FJ Cruiser Connection Points for Trailer Wiring, # 118405
    On the 2008 FJ Cruiser, the access points are going to be behind the taillights. The drivers side is the easiest. There is a small panel in the cargo area that you will remove and the taillight assembly will be right behind it. The passenger side requires loosening the trim panels on the passenger side cargo area to gain access to the taillight assembly. If your FJ Cruiser has the optional sub-woofer, it will need to be temporarily removed to gain access to the passenger side taillight...
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  • Parts Needed to Add 7-Way to 2012 Toyota FJ Cruiser
    You will need to start with a 4-way (if you do not have one). For that you would want the # 118405. From there you would need to convert the 4-way to a 7-way so that you can install the brake controller. For that you will want the Brake Controller Install Kit and 7-Way Adapter part # ETBC7. I attached installation instructions and an install video for this product as well. For a brake controller I would recommend the Prodigy P2 Brake Controller part # 90885. This is our best selling...
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  • Recommended 4-Way Flat Connector For 2008 Toyota FJ Cruiser
    We do not have a 14 gauge trailer wiring harness for your 2008 Toyota FJ Cruiser. We do have 3 16 gauge options that are confirmed as a custom fit for your vehicle, and that gauge is the industry standard for most trailer connectors. I recommend the Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118405. I've attached a video of this installation for you. If you want a 14 gauge wire, you can use the Curt Vehicle Wiring Harness with 4-Pole Flat Trailer...
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  • Trailer Hitch and Brake Controller Recommendation for 2007 Toyota FJ Cruiser
    You will need to start with a 4-way (if you do not have one). For that you would want the # 118405. From there you would need to convert the 4-way to a 7-way so that you can install the brake controller. For that you will want the Brake Controller Install Kit and 7-Way Adapter part # ETBC7. I attached installation instructions and an install video for this product as well. For a brake controller I would recommend the Prodigy P2 Brake Controller part # 90885. This is our best selling...
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  • Installing 7-Way Trailer Wiring Harness On 2015 Toyota Corolla To Match Trailer Connector
    You said you have a flat pin 7-way connector on your trailer. If the trailer has a round connector that has flat pins it is probably because the trailer has brakes. For your 2015 Corolla you would first need a 4-way connector and then a 7-way. The 4-way wiring harness I recommend is the T-One # 118405. This connector attaches to the vehicle wiring behind the driver and passenger side tail lights in the rear cargo area. You will need to remove some carpeting or interior trim to access...
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  • Lighting Solution for 2008 Camry Whose Tail Lights Are Blocked by Hitch Bike Rack and Bikes
    You are wise to consider this safety concern of your tail lights being blocked by your loaded hitch bike carrier. And we can give you an easy solution. A set of magnetic towing lights, such as the cost-effective Optronics # TL21RK, is an ideal solution since these are easy to install and store, and because they can be positioned on any metal surface that gives other motorists a good visual signal that you are braking. Their magnetic base holds them in place. Other options can be seen...
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  • No Running Light Power After Installing Trailer Wiring on a 2009 Toyota Camry
    It looks like the brake light and running light wires on harness # 118405 plug into the same location on a 2009 Toyota Camry. Check the converter wiring going into the converter to see if power is at that point since it is already at the tail light. If it is not on the brown wire going into the converter then check the connectors for bent or broken pins. If they you find a broken pin that harness will need to be replaced. A bent pin could be very carefully bent back. Make sure that...
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  • Trailer Wiring for 2016 Mazda 3 that Fits Sedan/Hatchback with or Without LED Lights
    I have an easier solution for you, but at this time Curt does not list any of their trailer wiring kits for the 2013 Mazda 3 as a fit if the vehicle has LED taillights. Instead we have the Tekonsha kit part # 118405 which fits all versions of the 2016 model including with or without LED lights and hatchback or sedan. Plus the Tekonsha kits have a reputation as having the most reliable converter boxes so we recommend them highly. I attached an install video for more info for you to check...
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  • Troubleshooting Trailer Wiring Converter Box that One Taillight Stays on After Brakes are Released
    Sounds like you have narrowed down the problem to possibly being on the converter you have installed on your 2011 Toyota FJ Cruiser, part # 118405. When converters go bad they can do all sorts of weird things, what you described sounds like it could be a bad converter. What you will want to do is test the wires going into the box of the converter box for voltage with a circuit tester like the # PTW2993 to see if there is voltage going into the box when the taillight functions of your...
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  • Brake Controller Installation for 2007 Toyota FJ Cruiser
    You're on the ball! That's exactly what you need. The Prodigy P3, part # 90195 is an excellent controller that's easy to use and very user-friendly. The # ETBC7 includes an adapter that will convert your 4-pole to a 7-way. The kit also includes all the wire, hardware and circuit breakers you'll need. I'll link you to some FAQ articles and installation videos that you might find helpful. These resources will walk you through the install, step by step.
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  • Which Trailer Wiring Harness is Recommended for a 2015 Toyota Corolla
    For your 2015 Toyota Corolla the Tow Ready Harness part # 118405 that you referenced is a confirmed fit and would work well. I attached an install video for you to check out as well. For a trailer hitch you would want the part # 24913 then as well. For a ball mount you would want the part # 3593. For a ball part # 19256 for a 1-7/8 inch ball and # 19258 for a 2 inch ball.
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