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  1. Custom Fit Vehicle Wiring
  2. CURT
  3. 4 Flat
  4. No Tow Package
  5. Trailer Hitch Wiring
  6. Vehicle End Connector
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2003 Chrysler 300C
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CURT

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

Part Number: C56218
138 Reviews | 13 Questions
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$73.73
Retail:$115.95
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 Custom Fit Vehicle Wiring
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2003 Chrysler 300C

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curt custom fit vehicle wiring trailer hitch plug-in t-connector harness with 4-pole flat connector
curt custom fit vehicle wiring end connector 4 flat c56218
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2014 ford transit connect custom fit vehicle wiring curt trailer hitch 4 flat t-connector harness with 4-pole connector
2014 ford transit connect custom fit vehicle wiring curt end connector 4 flat c56218
2014 ford transit connect custom fit vehicle wiring curt trailer hitch 4 flat c56218

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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. 1-800-940-8924 to order CURT custom fit vehicle wiring part number C56218 or order online at etrailer.com. Free expert support on all CURT products. Great prices 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 - C56218

Highlights

  • Custom Fit for Your Vehicle: Works with your vehicle's wiring
  • Tow Without Factory Prep: 4-pole flat connector powers trailer lights for safe towing.
  • Plug-and-Play Install: T-connector plugs inline at tail lights—no wire cutting needed.
  • Protects Vehicle Circuits: Powered converter draws from battery, not tail light wiring.
  • LED-Ready Design: Works with LED vehicle lights without causing signal issues.
  • Reliable Power Feed: Includes 12-gauge wire to run direct to battery for clean current.

Features to know about

Installs Fast Without Cutting Wires: Plug-In T-Connector

Wiring a trailer doesn’t have to mean cutting into factory wires. The Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector plugs directly into existing tail light connectors. It’s a clean, hidden install that taps into the vehicle’s wiring without splicing or modifying anything. Once it’s plugged in, you have a ready-to-use 4-flat connector for your trailer lights.

Protects Vehicle Electronics: Powered Converter Draws Directly from Battery

This harness uses a powered converter that pulls power straight from the vehicle battery through a 12-gauge wire. That design keeps the vehicle’s sensitive electronics protected from shorts or overloads that might occur on the trailer wiring. The tail light circuit only sends signal information, while the actual power comes from the battery, providing stable current to the trailer lights and safeguarding factory systems.

Ready for LED Lighting: Reliable Performance with Low-Draw Systems

LED lights on either the tow vehicle or trailer won’t pose a problem here. The harness uses its own power feed and signal converter so it can handle the low current draw of LEDs without issues. It provides smooth operation whether your trailer uses LED or incandescent bulbs, keeping turn, brake, and running lights working consistently.

Covers the Basics with Standard 4-Flat Connector: Brake, Turn, and Running Lights

The built-in 4-flat plug delivers all the essential lighting functions—running lights, turn signals, and brake lights—for most trailers. It’s the standard connection style found on small utility trailers, campers, and boat trailers, making it easy to hook up and go once installed.

Specs

Electrical Specifications

  • Power wire gauge: 12 gauge

Comparison diagram of the Curt T-Connector Vehicle Wiring Harness showing labeled connection points and wiring components for installation reference.


56218 CURT T-Connector - Surface Mount Technology - 4 Wire

Similar to Hopkins HM11140264 and Tekonsha 118613

Installation Details C56218 Installation instructions

This Product Fits The Following Vehicles






Customers Who Purchased This Custom Fit Vehicle Wiring Also Bought...



Customer Satisfaction Score:

Ratings & Reviews

4.8

138 reviews
5 Stars
(119)
4 Stars
(13)
3 Stars
(3)
2 Stars
(1)
1 Star
(2)
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by:
Love the product. Good integration with the vehicle wiring harness. The kit came with good accessories for mounting and wire management. One downside was the instruction to run a power line to the vehicle battery under the car. With the transit connect van, you have a fuse box near the rear passenger door, so makes more sense to go there for power. See pic of empty fuse slot used for power source.
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Nick S. profile picture
Etrailer Expert

Nick S.

9/29/2025

I am glad the installation was easy, and great point with the fuse box, I did not know that so I will keep that in mind moving forward! I am sure those photos will help many others in the future. What are you towing behind that Transit?

by:
Excellent quality wiring harness! Installation was very easy, and everything plugged directly into the factory connectors with no cutting or splicing required.

One thing to note is that you do need to run the power wire to the battery for proper operation. However, on my Ford there is a 12V power outlet in the rear cargo area, so I connected the power wire there instead, which made the installation even easier.

I’m very happy with this product and highly recommend it to anyone looking for a clean, factory-style installation.
by:
Works good. Needed about 5 more feet of black battery cord. Sad that Curt goes cheap and doesn't include the mounting bracket. Corner cut for sure. Being that the price of the bracket is 5$ and the screws are $1 (not to mention what they buy it for from China), pretty sad that you get nickeled and dimed.
Trevor profile picture

Trevor

4/3/2026

Seems to be working just fine.

by:
ive never come across a receiver with 2 different size pin holes till yesterday after i got it hung! pin wouldnt go all the way thru to put the hair pin in it. how does THAT,happen???
by:
Ordered a knock off plug and play online and after receiving 2 that didn’t function correctly but each with different issues, purchased the Curt and it was perfect
by:
This fixed out U-Haul connector problem
by:
I had a great experience with etrailer. The trailer wiring harness I ordered fit my vehicle perfectly and was super easy to install. Everything works exactly as it should — no issues at all. The product seems well made, and it was packaged nicely.

What really stood out was the service from etrailer — fast shipping, clear instructions, and great communication throughout the process. I’ll definitely be using them again for future trailer or towing needs!
by:
2016 Ford Transit-Connect
I love the etrailer it only took me 55 minutes to install I watched a how to video it was a great help , thank you very much
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by:
I installed the hitch and wiring In about 2 1/2 hours
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by:
This would be 5 stars but I took one star because I had to get a mechanic to fix my home install. Turns out, the whole time I could have tied in the power to a power outlet in the back of the van - I never needed to find a way to feed the power wire all the way up through the bottom of the van. Would have saved me $150.
by:
2014 Ford Transit Connect
I was kept informed of orders progress and was able to track it within 2hrs of delivery. Shipper did an excelant job box looked like new and product was in excelant shape when unpacked. Great how to instruction I read twice and checked under vehicle for corresponding access points. It went together in 16 mins and I didn't even jack up the vehicle. E trailer has great products with great staff and support. Well done crew!
Jerry A. profile picture

Jerry A.

12/27/2015

Product still performs flawlessly

by:
I am very pleased with my Curt T-Connector wiring harness, this is about the fourth curt wiring harness I've installed and I am installing it very soon.
by:
Directions were easy to follow. Easy to hook up except for the main power wire which had to be routed to the battery. but, doable and works great
by:
2014 Ford Transit Connect
I installed the hitch, but had an accessories place put the wiring in as part of another customization. I was a little spooked when I opened the instructions, said I'd have to run the ground wire all the way to the front, to the battery, (gulp! on my new car!) but I didn't recall seeing any note about why it can't just ground to the frame or something else nearby, so, though I bolted the receiver on no-brainer when I got the package a year ago, I had them do the electrical installation just a few weeks ago, as they're better set up to route and feed that ground wire. The hitch section has no issues, installation went absolutely by the book, no surprises. As far as I know no problems with any of the harness installation. I will say, I particularly like the large safety chain attach loops on these newer receiver models, much easier to feed the safety chain than other receivers I've gotten from these guys. Over the years when I've needed trailer stuff, I don't shop anywhere else.
by:
Had my mechanic install, works great a year later!
by:
2017 Ford Flex
This is an excellent product and everything fit nicely together. This product was used on a 2017 Ford Transit Connect XLT 7 passenger wagon. It was somewhat difficult to install on this vehicle as the rear access panels alone did not provide sufficient room to access the connectors. We had to partially remove the right rear and left rear panels by popping the plastic retaining pins out in order to pull the back panels far enough out to access the connectors. The rear seats do get in the way but assembly can be made by having a helper flex panels back far enough to access connectors without damaging panels. We followed the video provided by etrailer completely with the exception we ran the power wire up over and behind the insulated wheel well material on driver side rear wheel rather than down brake line and under heat shield. We also added plastic conduit to protect power wire from battery down to where it enters body leading to back. Total time took about 3 hours with two people and of course with not elevating vehicle. I advise at least 6 inch elevation.
by:
Worked great, and if I watched the install all the way through the first time it would have taken a quarter the time.
Gordon profile picture

Gordon

6/28/2025

Still going strong, zero issues.

Nick S. profile picture
Etrailer Expert

Nick S.

6/30/2025

@Gordon That is great to hear! I am glad its working great for you. What are you using this harness for?
by:
2012 Chevrolet Volt
Fast delivery!
The installation was not difficult, it went well. Watched videos from etrailer.com links, had no problems, all good fit. My only deviation from instructions was to run the 12 volt supply through the inside of the van to an existing relay. I keep it tucked into the jack compartment, pull it out when needed. Happy with this purchase.
by:
2021 Ford Transit Connect
Was a perfect fit for my vehicle in every respect. All parts needed were included and worked perfectly after installation. The videos of my vehicle were a big help. The tail light connectors are hard to get to but thats on Ford. Was also hard to run power wire under the van to the battery keeping it protected from rocks, hot exhaust and moving parts. But blame that on uni-body construction. I was able to do a good job, just took a while. Wish Ford included towing wiring as standard. This Kit is excellent.
by:
The Curt wiring kit all went together easily. I put the module on the R side vs L. I had power on the R already and had a convenient grommet to drop the trailer plug wiring thru for a permanent installation using the Curt flat 4 bracket. Doing this tho I needed to reverse the R and L turn wires and all worked well. Works great!
by:
Ford Transit Connect
Installation was easy. I have use the trailer connector a lot in the last year on my Ford Transit Connect with my own trailer and U-Haul trailers. Worked flawlessly. I would recommend to anyone needing trailer light wiring to purchase this item.
by:
The trailer hitch works great. It was easy to install.
The wiring harness was easy to install but i went threw the firewall instead of going under the vehicle.
by:
The wiring worked good, I am glad this is available to hook the turn signals and brake lights up on these new vehicles. Wire harness is different on these new cars, not like the old days,,
by:
I bought two of these kits and have installed one of them, video was very helpful and informative took me a little while longer when it came to getting under the vehicle wiring but worked out very good . I put the hitch and wiring harness to move a small trailer around have hitches and wiring kits on both transits.
by:
Assembly was a little more difficult than the video shows with connect t connectors because the "right" connector on each side is more difficult to locate and get christmas tree fasteners loose. I chose to route the 4 pin connector through same route as power wire and had to cut grommet to do that. Routing the plug through the fender opening to get to underside of vehicle required me to trim some bosses of each side of plug and use a long thin rod to guide plug completely through. I preferred this to having the trailer plug loose inside the vehicle. It was worth the hassle. I resealed the grommet afterwards with sealant. The biggest word of caution is the amount of black power wire provided does not give you any extra to work with getting to battery on long wheelbase wagon. I had to add 3‘ to be able to pull it up to battery and work with it.
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See what our Experts say about this CURT Custom Fit Vehicle Wiring

Do you have a question about this Custom Fit Vehicle Wiring?
  • Load Resistors to Allow Wiring Harness to Operate with LED Trailer Lights
    LED type trailer lights use very little power, about one-tenth the amount required by standard incandescent light bulbs. This can cause some wiring systems to not "see" the trailer lights because their current draw is so low. In some cases a wiring harness may not function correctly if used with LED lights unless a load resistor is installed at each LED light unit. We offer 2-piece ceramic load resistor kit # DI34ZR which will allow your harness to operate properly with LED trailer lights....
    view full answer...
  • Troubleshooting Side Marker Lights Not Working With Curt 4-Way
    Hey Kurt! I would start by double-checking the ground connection on your Curt Wiring Harness # C56218 and making sure it's still securely attached to a clean, bare metal surface. If your trailer has LED lights, the lights staying on with the vehicle turned off may just be residual voltage, so I wouldn't be too concerned about that yet. The 7V reading is what I'd focus on. I would test the running light circuit at the 4-way with the trailer disconnected, then check the voltage directly...
    view full answer...
  • Curt Wiring Harness Compatibility with 2018 Ford Transit Connect
    I reached out to my tech contact at Curt and they have confirmed the fit of the wiring harness # C56218 for the 2018 Ford Transit Connect on the Titanium, XL, and XLT trim packages. Do you have a different trim package?
    view full answer...
  • 4-Pole Trailer Wiring Harness for 2014 Ford Transit Connect
    Many of the 4-pole trailer wiring kits we sell will install at the vehicle's tail lights. The harness connectors on such kits install in between the vehicle plugs and the tail lights themselves. For the 2014 Ford Transit Connect we have three such products, all shown on the linked page, and all of these use custom connectors selected to match those on your vehicle. Of the three we have I recommend the Tekonsha # 118613 since we find their wiring products to be the most reliable. If you...
    view full answer...
    Image 1 for
  • Trailer Lights Are Always Powered After Hooking Up To Vehicle
    Hi Tony! I don't want to just jump in and say it's defective as it might not be. Whenever we hear something weird happening (and this is definitely in the weird category), it's almost always the ground causing the issues. So to start, make sure the ground for the Curt T-Connector # C56218 you installed has a good clean area it is attached to. I also urge you to not have that ground "stacked" with other ground (multiple grounds on one bolt/screw) as I have had problems with that kind of...
    view full answer...
  • Parts Needed to Install Brake Controller in a 2016 Ford Transit
    To install a brake controller in your 2016 Ford Transit Connect tou will need to start with a 4-way (if you do not have one). For that you would want the # C56218. 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...
    view full answer...
  • Curt Wiring Harness C56218 Acting Weird After Installing On 2018 Ford Transit Connect
    Hi Charles! Sorry to hear the Curt # C56218 is acting up, but I can definitely help with that. First, make sure all the plugs are fully seated and snapped together. That probably isn't the cause, but it is a good thing to double check. Second, make sure your ground is on a good and clean metal surface that isn't aluminum (which can be somewhat of a problem these days). Also make sure the ground isn't "stacked" with other grounds. It's always best for each ground to have it's own source. If...
    view full answer...
  • Gauge of Power Wire for the Curt Trailer Wiring Harness part # C56218
    The gauge of the wire that runs to the battery for the Curt harness part # C56218 that you referenced is 12 gauge.
    view full answer...
  • Are LED Trailer Taillights More Likely to Blow Fuses than Incandescent Bulbs
    LED taillights would not cause trailer wiring circuits to blow as they actually draw considerably less than incandescent bulbs. So that means there is a short on the wiring somewhere on the trailer. If you have no circuits active on your trailer wiring and you are getting continuity from the power wire of a circuit to ground that would indicate that circuit is shorted out to the trailer frame most likely due to cut or exposed wire that is contacting the frame. You'd need to go over the...
    view full answer...
  • Recommended 4 Flat Harness For A 2016 Ford Transit Connect
    The powered black converter boxes from Curt are not available separately, so I do recommend replacing it with a custom fit, powered option. We do have the # C56196 converter, but it is not a powered unit. With your 2016 Ford Transit Connect not having enough power to get the lights on a trailer working though, I do not recommend this option. With that being said, these do go out over time and I have found that the Tekonsha T-One Vehicle Wiring Harnesses, like the # 118613, are the superior...
    view full answer...
  • Is Drilling Required to Install the Curt Hitch part # C12123 on a 2014 Ford Transit Connect
    You will not need to drill any holes in your 2014 Ford Transit Connect to install the Curt Hitch part # C12123. Check out the installation instructions I attached for this hitch as well. For trailer wiring you would want the Curt Wiring Harness part # C56218. For a ball mount you would want the part # C45521, pin an clip part # F-4, 2 inch ball part # A-82, 1-7/8 inch ball part # A-80.
    view full answer...
  • Can 12-Volt Connection for Powered Taillight Converter Be Connected to 12-V Outlet
    This is a common question. Theoretically, what you propose could work but it isn't recommended. Drawing the power directly from the battery helps isolate the vehicle's expensive to repair electrical system from any short circuits that could occur in the trailer wiring, which is why the trailer harness manufacturers recommend installing a direct battery connection. I've linked to the installation instructions for the Curt # C56218 trailer wiring harness, an install video and a help article...
    view full answer...
  • Can Curt Trailer Wiring Harness be Installed on a 2014 Ford Transit Connect with LED Lights
    Ford probably thinks that the trailer wiring harness # C56218 draws all of the power it needs through the tail light wiring. But it doesn't. This harness powers the trailer lights from the vehicle battery and only uses the tail light connection on the vehicle for the proper signals to send back to the trailer lights. LED tail lights on the vehicle would not pose a problem.
    view full answer...

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