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

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

Item # C56407
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Custom Fit Vehicle Wiring

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Curt Custom Fit Vehicle Wiring - C56407
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Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. T-connector plugs directly into existing wiring. Powered converter reduces strain on wiring system and is made using SMT to ensure superior performance. Call 800-298-8924 to order Curt custom fit vehicle wiring part number C56407 or order online at etrailer.com. Free expert support on all Curt products. Guaranteed Lowest Price and Fastest Shipping for Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector. Custom Fit Vehicle Wiring reviews from real customers.
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Curt Custom Fit Vehicle Wiring - C56407

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

Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. T-connector plugs directly into existing wiring. Powered converter reduces strain on wiring system and is made using SMT to ensure superior performance.


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 a powered tail light converter that connects directly to your battery to avoid overloading your vehicle's electrical system
  • Constructed using surface-mount technology (SMT) for consistent, reliable performance
    • Maximizes trailer light yield and intensity while producing minimal heat
    • Ensures superior operation in rough road conditions
  • Comes with dust cap for 4-way flat connector


Specs:

  • Maximum amperage:
    • Stop/turn lights: 3.0 amps per circuit
    • Tail lights: 6.0 amps per circuit
  • Limited 1-year warranty


Installation

This custom-fit T-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 trim access cover, scuff panels, and tail lights to access these connection points. Once you've plugged in the T-connector, run the hot lead to your car battery, which can be found in your trunk on the passenger's side. Connect the lead to the included fuse holder, and then connect the fuse holder to the positive terminal on your battery.


Once installation is complete, the 4-way connector will be stowed in an out-of-the-way location within your trunk.


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.


Powered Tail Light Converter with Surface-Mount Technology

A tail light converter is built into this T-connector. This converter is a circuit-protected, battery-powered unit that bypasses the electrical routes that are used by a basic wiring harness. As a result, there is virtually no draw on your tail light circuits.


Curt builds each tail light converter using surface-mount technology (SMT). This method of construction involves soldering electronic components directly to the surface of a printed circuit board. SMT eliminates the need for leads, which are used in older through-hole technology. The result is a circuit board that is smaller yet provides more routing area and that offers superior performance, reliability and durability.


Curt SMT Circuit Boards

Circuit boards constructed using SMT have been shown to perform better under rough conditions with excessive vibration than those made using the through-hole method. And where would vibration be more likely to occur than in towing applications? Curt converters also produce less heat, leading to increased durability and longer life. In addition, lower levels of resistance ensure better performance, especially for parts that operate at higher frequencies.


Each Curt circuit board is made using high-quality components that are pieced together in the most technologically savvy fashion, leading to greater predictability and reliability in functioning.



56407 Curt T-Connector - Surface Mount Technology - 4 Wire



C56407 Installation InstructionsInstallation Details C56407 Installation instructions

This Product Fits The Following Vehicles

2018 - 2018 Jeep JL Wrangler

2018 - 2018 Jeep JL Wrangler Unlimited

2019 - 2020 Jeep Wrangler

2019 - 2020 Jeep Wrangler Unlimited

2020 - 2020 Jeep Gladiator without factory Tow Package

2018 - 2018 Jeep JL Wrangler without factory Tow Package

2018 - 2018 Jeep JL Wrangler Unlimited without factory Tow Package

2019 - 2020 Jeep Wrangler without factory Tow Package

2019 - 2020 Jeep Wrangler Unlimited without factory Tow Package



California residents: click here


Video of Curt T-Connector 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 Curt T-Connector Vehicle Wiring Harness Installation - 2018 Jeep JL Wrangler Unlimited

Speaker 1: Today on our 2018 Jeep JL Wrangler Unlimited, you're gonna be taking a look at and I'm gonna show you how to install the Curt T connector vehicle wiring harness with four pole flat trailer connector, part number C56407. This is what our wiring looks like when it's installed. This is gonna give us all of the proper lighting functions to safely tow our trailer down the road. It's gonna give us both turn signals, our running lights and our brake lights. It's gonna come with an included dust cap that's gonna help keep all of our connections clean from any dirt and debris. This particular hitch has a welded on bracket on it.

If your hitch does not, you can use your dust cap as a holder when you're not using your plug. That'll help keep it off the ground, help keep it from hanging down. Your hitch does have this bracket. You can use a four pole bracket, which is sold separately. But you can find it here at etrailer.com.

It'll mount right to that bracket and that'll give your plug a more permanent mounting location.If you do not have this welded on bracket, along with this four pole bracket, you will need a no drill mounting bracket. It's gonna be a long bracket and how that works is it's just a long bracket that'll mount right to the bottom of your hitch. It has a clamp that comes with it. It'll stick out and then this will mount right to it. That'll give your four pole, again, a more permanent mounting location.

Now that we've gone over some of the features of our four pole wiring, let's show you how to get it installed. You're gonna have your power wire that's gonna run from the back of your vehicle or from your converter box to your battery in the front. You're gonna have your fuse holder that's gonna mount on the end of your wire in between your battery and your connection. You're gonna have your wiring harness, which is gonna plug directly into your factory wiring. You're gonna have your power wire coming off your converter box, which gets connected to your wire inaudible 00:02:01 extension to run to your battery and you have your grounds.You have your four pole plug, which is gonna give you all your functions to the trailer or whatever it is you're pulling.

Another thing that's really good about this box is your wires come in the back. They all come in one side. They connect to your circuit board in here. Well, this potting material right here fills up this hole inside. So what that does is it really breaks down on any vibration that that connection or the connections to your wires make on the circuit board take. If this box happens to come loose, that potting material in there is gonna really hold those connections onto that circuit board really well. So that's a really good about this box, unlike some of the other ones out where the wires come in both sides. So with that, you're also gonna get the little installation kit, ring terminal, your fuse, a couple of butt connectors. One thing I do want to say about the butt connector's, though, because this is gonna be outside of the vehicle, I recommend changing those out for heat shrink butt connectors. You can find those here at etrailer.com using part number DW05745.Now that we've gone over some of the features, let me show you how to get it installed. First thing we need to do is we need to remove our taillights. In order to do that, you're gonna come inside the vehicle, the back of the vehicle. You're gonna have a little access panel right up here. Take a little screwdriver. You can see that little notch there. Pop that off. Take a 10 millimeter socket. You're gonna take off that spring bolt in there or spring loaded bolt there. Once you get that off, you're just gonna pop your light out like that. Red tab, pull up on it. You're gonna push down on this black tab here then pull it apart. You're gonna do that same thing to the other side of the vehicle. Here on our driver's side, we're gonna take our green or the plug with the green wire and our four pole plug. We're gonna go right back in the taillight pocket. There's a hole that goes right down to the outside of the vehicle. I'm gonna go ahead and push those down and through there. We're gonna have some two sided sticky tape.We're gonna stick it right back on our converter box here. I'll take this and I'm gonna stick it right down in the bottom. There's a big flat spot down there. Now we're gonna make our connection to our factory wiring. One thing I suggest doing is using a little bit of dielectric grease. It's gonna protect all your connections from any moisture or corroding. Don't forget your red tab and then we'll do the same when we put our light back on. We're gonna do a couple other things here first. We're gonna go ahead and make our connection to our power wire that's gonna be running up to the front and then we'll take it, hooking it onto the black wire from our converter box. Then we'll take our heat source and we'll shrink up our butt connector. Now we'll take our self tapping screw. Our ground wire just needs to be grounded to metal. I'm gonna ground it right here along this inside body panel here. Now we can install or reinstall our taillight. Push it in until it snaps. Make sure you push the red tab back in.Then we'll reinstall our spring screw or spring bolt, however you want to look at it. Now we're gonna route our green wire and our four pole. Four pole, we're gonna stop right here. Green wire, we're gonna route all the way across to the passenger's side. What we needed to do is take an 11 millimeter socket. You're gonna have two aluminum nuts here on the end of your heat shield. Go ahead and pull those off and then slightly pull down on your heat shield. Take your green wire. Run it over the top of your frame rail and right above your heat shield over to the other side. Then all we need to do here on our passenger side is make our wire connectors on our plugs. Now we're gonna route our power wire up to the front of our vehicle. Keep in mind, our battery is on the passenger side here. So we want to make sure however we decide to route it, we're giving ourself enough wire to make our connection onto our battery. Let me get this done real quick and I'll show you how I did it.So the way I ran my power wire, I ran it the same way I did my green wire that ran over to my passenger side, over the top of my heat shield and what I did is I went through the frame rail. You can see this hole here. I took an airline tube. If you don't have any, you can find some here at etrailer.com. It works great for running stuff like this. There's holes that run all the way down the frame rail. I just ran my airline tube through the holes as I walked it up to the front of the vehicle and came out of this hole. I have an airline tube down from my battery, which is hanging right here. Again, this particular one has dual exhaust. So you want to make sure you stay away from heat or anything moving. Take your wire. Put it in the end of your airline tube. That will go up top. Pull our airline tube up into a little inaudible 00:08:08. Once you pull it up, just double check to make sure you're not snagged on anything down there.Then we're just gonna connect it right onto that post there. So I routed my wire around my fuse box here, zip tied it right here to this wire. This way, I can hide my fuse holder right down in between my battery and my fuse panel here or fuse box. So we'll go head and cut this down inaudible 00:08:40 shrink butt connector. Take one end of our fuse holder. Ring terminal on the other end. Then once we make our connection to our battery, we'll put in our fuse. Take a 10 millimeter socket. Go ahead and loosen your nut. Put that on and replace the nut. Go ahead and put your fuse in. Take your wire. You can tuck it right on like that. Now we'll test out our wiring using part number I26. Left turn. Right turn. Brake lights. Running lights and that'll do it for the look at and installation on the Curt T connector vehicle wiring harness with four pole flat trailer connector, part number C56407 on our 2018 Jeep JL Wrangler Unlimited.


Customer Reviews

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - C56407

Average Customer Rating:  4.9 out of 5 stars   (48 Customer Reviews)

Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. T-connector plugs directly into existing wiring. Powered converter reduces strain on wiring system and is made using SMT to ensure superior performance.

- C56407
by:

Product works as advertised. The only very small issue, I wished the wiring for the passenger side would be a little longer. 662764



- C56407
by:
2018 Jeep JL Wrangler

Directions were a little vague. 569714



- C56407
by:
2018 Jeep JL Wrangler Unlimited

Curt has just made one Rubicon JL owner very happy. This product works great and I didn't have to spend the big bucks for the Mopar version. One small problem, the green wire to right side tail light could have been ten inches longer. 526294



- C56407
by:
2018 Jeep Wrangler

Product worked out great. The customer service was even better, no one contacts you anymore to let you know there is another part number available after the original order was placed, etrailer did!!! Thanks for the great overall service! 2018 Jeep Wrangler Unlimited Sport JL!! 539217



- C56407
by:
2018 Jeep JL Wrangler Unlimited

Shipped when stated and completely. Also had available video to aid in install. Very pleased with all aspects of purchase and using on my 2018 JL Unlimited. Also purchased the Hitch and was more than happy with this has well. Thank you and I’ll be checking out other things to add to my Jeep in the coming months/years. 591634



- C56407
by:

Easy install. Video is super helpful. You could pay $750 for a dealer installed tow package or buy this bad boy and a receiver for less than $200. $50 more bucks for beer and you still come out on top. Would buy again. 690626



- C56407
by:
2018 Jeep Wrangler

Installed on my 2018 Wrangler JL 2 door. It took me about an hour with help but we were taking it slowly. The install video on the product page is excellent. I watched it ahead of time and again, bit by bit, while doing the job. I’m very happy with the final results. 612629



- C56407
by:

This wiring harness has very easy instructions no problem everything works like it should very good product save me a ton of money dealership said major wire job will be $1000 which was crazy it was a plug and play with one wire running to the front and connecting to the battery 637713



- C56407
by:
Jeep

Today I installed the harness - took me 2 hours but was EASY. - $93.25 (the one thing I am proud of is that I got so strategic with my wiring that I NEVER used a zip tie :). Also I didnt even have to drill through the firewall. Ran it under the jeep on the drivers side then up through hood and over to battery. I made sure the wires and VERY hidden (I ran them inside of the opening of the rock rails) and away from anything that could get potentially hot. NOTABLES: 1. I had to add about 10 inches of wire to the passenger side (used heat shrink connectors). 2. The connector for the battery is too big for the smaller wires. I used a slightly smaller one and worked perfectly. 541924


Comments
Its perfect! Would buy it again if I had to in a heartbeat!
Dustin - 07/15/2019

57817

- C56407
by:
Jeep

Worked great on my 2018 rubicon JL w/LED lights easy plug n play. Hardest part is hiding wire underneath Jeep. Ran power wire along side carpet and pannels, tucked it underneath pannels. Ran it thru grommet on fire wall on Driver side then to battery. 570791



- C56407
by:
2018 Jeep Wrangler

Hally was super helpful with my order of the wiring harness for my 2018 Jeep Wrangler Sahara JLU. Thank you! 538525



- C56407
by:
2018 Jeep JL Wrangler Unlimited

Wow, extremely easy install, this is how I did mine; take drivers side lamp out. Phish down to the ground, the passenger side green harness, the pos and neg wires. Now plug up yellow harness to drivers lamp, mount power module with tape inside the housing area and close back up. From underneath run pos to battery, neg to a bolt, passenger side to that lamp. Done. 525904



- C56407
by:
2018 Jeep JL Wrangler Unlimited

Maiden voyage with the wiring harness and seven pin adapter and protective loom. etrailer has the products and associates to back it up. Terrific support, videos and live help if needed. Perfect fit parts. Value and quality can't be beat. Thank You etrailer. 544054


Comments
Flawless. Im going to have a brake controller installed at an RV place. Moving up to a small self contained trailer. I hope that there are no issues at that time.
Peter F - 07/14/2019

57806

- C56407
by:
2018 Jeep JL Wrangler Unlimited

Ordered the receiver wiring harness for my '18 Wangler JL. Been looking for one which isn't a shortcut or over priced. Very impressed with the ordering process and follow through with eTrailer.com. When the box was delivered, received an email from eTrailer informing me it was delivered. Ran the power wire from the battery to the driver side in the wiring channel located on the back firewall of the Jeep. Drilled a hole in the top plug just large enough for the wire to squeeze through to prevent water creeping in. Then gently wrapped the power wire around the wiring harness to the back tail light, zip tying occasionally. Bonded the control unit (with a little JB weld to help the sticky tape over time). Ran the wires across to the receiver and other tail light. Then connected the battery using the fuse link provided. In total, the effort took 1 hour and 15 min. Kit contained everything I needed. Fantastic experience with eTrailer.com 541305



- C56407
by:
2018 Jeep Wrangler

The kit worked on my 2018 jeep wrangler JL unlimited. It took about 3 hours to install. It was not difficult to do. It just takes time to run the wire to the battery (there are videos out there saying you need to pull apart the back compartment. It is not needed. You can feed the wire up alongside the other taillight wire and then just tuck it behind the carpet and the plastic all the way to the engine compartment). 549298



- C56407
by:

Better than I expected. Great products! Great service with delivery, internet chat and phone. People that still care.... nice 738346



- C56407
by:

Great Product! Excellent Service! 730842



- C56407
by:

Installing was not too difficult just time consuming. Video was a great help only needed to add 2 extra zip ties and shrink wrap. Shrink wrap connectors should have been provided with the harness 723406



- C56407
by:

This kit is complete an looks like it will work perfectly. 723112



- C56407
by:

Harness was easy to wire up. Self explanatory. No issues after installation. Button everything up. Good to go 716243



- C56407
by:

This product was easy to install and preforms great no problems. I installed on a new JL Wrandler. 706832



- C56407
by:

Great product the instructions are very easy to understand 696091



- C56407
by:
2018 Jeep JL Wrangler

I watched the installation video thank you, it helped a lot everything went as planned I followed the instructions to a tee and it took about an hour. The only thing they didn't cover was the passenger side wiring I took off a small cover at the bottom of the wheel well to fish the wiring through and I used my fish tape to push the hot wire through the frame it made this task simple. Great fit great product 694998



- C56407
by:
2019 Jeep Wrangler

Install took about 45 mins Haven’t used the trailer yet YouTube video helped 694615



- C56407
by:

Everything was complete easy to install with video thanks 683107


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    The best choice for 4-way trailer wiring for your 2018 Jeep Wrangler JL is the T-One kit part # 118786. Reason is it has higher amperage ratings so it would be more difficult to short out and because T-One in general just makes more reliable trailer wiring for vehicles.
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    Not all vehicles can handle the additional amperage draw of the trailer taillights on the vehicle taillight circuits. Those vehicles need setup that draws power from the battery. Some vehicles have higher rated circuits that can handle this, and others need to have the power drawn straight from the battery to protect the taillight circuits. While it seems easier to just run the power wire to an available accessory circuit it's not the best idea to go that route. In the event of a short...
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  • Recommended 7 Way Wiring and Brake Controller for 2020 Jeep Wrangler Unlimited
    To install a brake controller on your 2020 Jeep Wrangler Unlimited you first need 4 pole wiring to provide all the lighting functions, like the Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # C56407. Then use the Universal Installation Kit for Trailer Brake Controller # ETBC7 to convert to a 7 way, the 4 pole wiring plugs into the 7 way, and comes with all the wires and connectors to hook up your brake controller. For a brake controller I recommend the...
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  • Will 4-Flat and Tow Bar Wiring Both Work on 2018 Jeep JL Wrangler Unlimited
    The Curt T-Connector Vehicle Wiring Harness # C56407 and Tow Ready Tail Light Isolating Diode System # TR118821 will absolutely work together on your 2018 Jeep Wrangler JL Unlimited to give you a 4-way at the rear of your Jeep to tow your trailer and at the front to flat tow. The reason for this is the Curt connector will plug into the tail light housing while the Tow Ready will splice in; I recommend starting with the Curt and then installing the Tow Ready. I have added a link to an...
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  • Which Curt T-Connector Fits a 2018 Jeep JL Wrangler
    We do have a Curt T-Connector that fits a 2018 Jeep Wrangler JL but the part # C55124 that you referenced does not fit. Instead you need part # C56407 which tees in behind your tail lights and then draws power directly from your battery via the included black wire. The great thing about drawing power directly from your battery is that your vehicle wiring is completely protected in the event that something goes wrong with your trailer wiring. Attached is an installation video of this...
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  • Easiest Solution for Installing 7-Way and Brake Controller in 2018 Jeep Wrangler Unlimited
    I have just the simple solution you are looking for to easily add a 7-way and brake controller to your 2018 Jeep Wrangler JL Unlimited... Basically you have to start out first with a 4-way which covers the lighting circuits of the trailer wiring. For that the easiest and most reliable solution is the Curt kit part # C56407 which installs by plugging inline with the taillight connectors of the Jeep. I attached an install video to use as a guide for this to make it as easy as possible....
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  • Parts Needed To Install AutowBrake Brake Controller With 2020 Jeep Gladiator
    The only part needed on a 2020 Jeep Gladiator to install the AutowBrake Brake controller part # 3430001 is a 7-way connector at the rear of the Jeep with an active 12V circuit and turn signals. The Autowbrake installs on the trailer side and wires to a junction box where your trailer wiring functions are connected to the corresponding stud. It activates the trailer brakes based off the brake/turn signals of the Jeep not the stop light switch so the 7-Way blue wire is not required. I have...
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  • Recommended Trailer Wiring For 2018 Jeep Wrangler Unlimited Rubicon With Factory Package
    If you the factory tow package with a 7-way you can replace the 7-way with the Curt Trailer Connector for Ford and GM Trucks - Backup Alarm part # C57101 which connects to the towing port on the 2018 Jeep JL Wrangler Unlimited as confirmed by Curt. If you do not have the port you will need Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector part # C56407 which plugs in behind the tail lights. This is only a 4-Way though to illuminate the trailer lights so I believe...
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Info for this part was:

Edited by:
Lindsey S
Installed by:
Jeff D
Expert Research:
Jameson C
Video Edited:
Jacob T
Video Edited:
Dustin K
Video Edited:
Chris R
Written by:
Ronnie R
Test Fit:
Shane H
Test Fit:
Robert C
Video by:
Jonathan Y
Video by:
Michael B
Updated by:
Kristina F
Updated by:
Isabelle B

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