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  2. CURT
  3. 4 Flat
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  5. Trailer Hitch Wiring
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2014 Nissan GT-R
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CURT

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

Part Number: C55400
31 Reviews | 8 Questions
In Stock
$66.34
Retail:$100.95
You Save: 34%
 Custom Fit Vehicle Wiring
Not Confirmed to Fit

2014 Nissan GT-R

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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 C55400 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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  • Reviews (31)
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CURT Custom Fit Vehicle Wiring - C55400

Highlights

  • Custom Fit for Your Vehicle: Works with your vehicle's wiring
  • Tow Without Factory Prep: 4-way flat connector powers trailer signal and brake lights.
  • Protects Vehicle Circuits: Powered converter draws from battery to prevent overload damage.
  • Plug-and-Lead Setup: Hidden harness mounts cleanly for a factory-style finish.
  • Works With LED Lights: Supports modern trailer LEDs without flicker or wiring mods.
  • Ready for Hitch Mount: 4-flat plug pairs with mounting brackets for a tidy receiver-area fit.

Features to know about

Protects Vehicle Wiring: Powered Converter Draws From Battery

Factory tail light circuits aren’t built to handle extra load from trailer lights, and overloading them can cause blown fuses or worse. This harness uses a powered converter that takes its power directly from the vehicle’s battery, keeping the taillight circuits safe while still delivering full current to your trailer lights.

Ready for LED Trailers: Works with Modern Lighting Systems

LED trailer lights pull less power but can confuse older wiring setups. This T-Connector is built to handle LED trailer lights without flicker or warning errors. It delivers stable performance whether you’re pulling a small utility trailer or something with a full LED light setup.

Clean Install with Plug-In Design: No Cutting Required

Instead of splicing into factory wires, this harness plugs in using vehicle-end connectors. The install is straightforward, uses existing factory plugs, and keeps everything hidden and secure. It’s a simple way to get a 4-pole flat connector without altering your wiring.

Covers Basic Trailer Functions: 4-Flat Connector Output

The included 4-flat trailer connector provides running lights, brake lights, and turn signals—the essentials for towing safely on the road. It’s the standard plug style used on most light-duty and utility trailers, so you’re ready to tow right away.

Specs

  • Comparison image displaying Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector, showing labeled plug-in harness components and wiring layout for installation reference.

55400 CURT T-Connector - Surface Mount Technology - 4 Wire

Similar to Tekonsha 118413 and Hopkins 33425

Installation Details C55400 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

31 reviews
5 Stars
(28)
4 Stars
(1)
3 Stars
(2)
2 Stars
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1 Star
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by:
2006 Toyota Highlander
Got the hitch that was made for the year and model of our car. It was super easy to install. It bolted right on easy as pie. It is out of the way and looks nice. It is built strong and I am completely comfortable towing with it.
I also got the wiring harness to go with our car. Took a few minutes to remove and reinstall some of the inside panels but was not a problem. The wiring harness connected easy. Fit like a glove. Am very happy with the products. And the service I got was great.

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by:
2005 toyota Highlander
Good quality item, fit easily in my 2005 Toyota Highlander Base. There was no need to purchase the wiring harness for a non-tow package car as the car already had a plug for the towing wiring! Still worked fine splicing the 12v lead from the factory tow connector plug directly to the towing relay from the kit. Required removing several interior trunk panels, needed a phillips-head screwdriver, 10mm socket wrench, and a trim tool.
by:
2004 Toyota Highlander
Pretty easy to install except for the main power all the way to the battery
by:
2007 Toyota Highlander
The trailer hitch receiver and wiring harness a are working great. I am very happy.
Ron profile picture

Ron

2/20/2018

The trailer hitch and wiring have been working just fine.Thank you!

by:
2005 Toyota Highlander
Simple "plug n play" harness. The most difficult part was routing the wire from the battery to the back of the vehicle. The instructions were sparse, but now that I've done it once, I know how to do it easier and quicker. All in all took me about 30 minutes.

The existing rubber grommet for the vehicles wiring harness on the firewall of the Highlander has an extra nub that you can cut off to reveal an existing pass through hole. After that be sure that you have removed all of your floor trip pieces ahead of time, and fashion a hook out of a coat hanger and feed it through the trip piece between the doors to pull the wire through. Do the same for the trip piece over the wheel well, and only remove the cup holder panel.

You can also choose to splice the fuse at either end. I'd recommend at the battery end for ease of access. Be sure to crimp the connector to one end of the red fuse wire to connect to the battery, and the other to the black wire.
by:
2003 Toyota Highlander
Trailer Hitch fit my 2003 Toyota Highlander. Installation is a two-person job. I use this trailer hitch to tow my Kayak Trailer. I’m a satisfied with this product!
by:
2006 Toyota Highlander
I love it! I've been wanting a hitch on my 2006 Highlander to tow my fourwheeler, and my uncle recommended buying from etrailer. I am very pleased, and I'd definitely order from them again. The hitch and wiring came with instructions but since I had never installed one before I didn't understand them all that well. However I was able to find several videos that made it so much easier. It took me about 4 hours total to install the hitch and the wiring, and they're working great so far!
by:
Great product. Easy to install.
Will definitely buy from etrailer again.
Brooke M. profile picture
Etrailer Expert

Brooke M.

6/9/2025

Aw, that's great, Luis! Thank you very much -- really happy to hear that everything is well even after a year :)

by:
I gave it a good because it's only been working one day. In ten years I'll give it an excellant.

However, I think I ordered more than I need. I'm not running a lot of lights. But the cost isn't the major issue; it's the time it takes to figure out how to thread the power wire from the battery to the convertor. Really, no help on that subject. You just got to figure it out yourself.

Secondly, there is no video for the C55400. I used the video for the 18something to figure out how to thread the wires from side to side and store stuff. Convertor and yellow wire on the driver side, green on the passenger. It wasn't hard after viewing that.

So, if you're not running a bunch of lights, go with the cheaper one. You don't have to crawl on your back strapping the wire to the undercarriage.
by:
2005 Toyota Highlander
Great product, timely delivery, will now use my trailer safely with the electrical hook up. Convenient to be able to find the wiring for my vehicle and not some generic wiring, plus the instructions are great. Thank you.
by:
2007 Toyota Highlander
Excellent pricing and outstanding service! Instructions for installation make ETrailer #1 source for DIY. High recommendations for everyone! Thank you!
by:
2015 Toyota Highlander
I needed to replace the converter on my Highlander for my trailer lighting. A replacement was sent after supplying the information from my old one which I installed in about 15 minutes. Working wonderfully! These guys rock!
by:
2001 Toyota Highlander
Very simple plug and play on the tail lights, connect your ground wire, and run the power wire up to the battery.
by:
Well designed and easy to install!! Great how too video if you needed it, I watched that before I ordered it and was 100% ready when it arrived! Fast delivery!
by:
just ordered my second hitch in a week. very easy to order on the phone and both came quickly- very happy
by:
The items arrived in excellent condition, exhibiting high-quality materials and construction.
by:
exellent products and quick delevery time.
by:
2003 Toyota Highlander
Products quality seems very good. Very easy to install
by:
2006 Toyota Highlander
Extremely easybto use.
by:
Install was a cats meow.
by:
Wiring harness installed as expected. Good instructions.
by:
Easy to install and works great.
by:
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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?
  • Which Trailer Wiring Harness for 2007 Toyota Highlander
    The correct trailer wiring harness for your Highlander will depend on whether or not it is equipped with the tow package and the lighting set-up of the trailer you will be towing. If your Highlander has the tow package, and you will be towing a trailer with very basic lighting (one stop/turn/tail light per side) then the Tow Ready # 118248 would be a good choice. If your lighting is a bit more complex, you would need a harness with a higher rated converter like the Curt # C56107. If you...
    view full answer...
  • Why Does Curt Trailer Wiring for 2006 Toyota Highlander Require Running Power Wire to Battery
    Not all vehicles can handle the additional amperage draw of the trailer taillights on the vehicle taillight circuits. Those vehicles need a 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. For your 2006 Toyota Highlander you need to install a harness that draws power from the battery to protect the taillight circuits. For that you would...
    view full answer...
  • Adding Reverse/Backup Wire To A 7 Way Plug On A 2002 Toyota Highlander
    Yes we do have the parts you will need to add a reverse wire to your 2002 Toyota highlander. If your vehicle already has a 7 way plug, you will simply need to connect the auxiliary circuit (usually yellow) wire to the reverse light circuit on your vehicle. You can do this using 14 gauge wire # DW02412-1 and a quick splice connector # SWC502905-1. If your vehicle only has a 4 flat plug currently, you can use our Universal Install Kit # ETBC7 to add on a 7 way with a reverse wire. If you...
    view full answer...
  • Wiring Kit to Add 4-Way Connector to a 2006 Toyota Highlander
    We do have wiring kits to add a 4-Way connector on your 2006 Toyota Highlander Hybrid that doesn't have the tow package. If you are wanting a kit that plugs in behind the tail lights like the Curt T-Connector # C55400 that you referenced, there are none that connect that way as they involved splicing the wiring in. Out of our available selection I recommend using the Tekonsha # 118413 as we have found that Tekonsha has the most reliable wiring kits. This includes a protected ModuLite and...
    view full answer...
  • Recommended Trailer Hitch & Wiring Harness for 2001 Toyota Highlander
    We offer two sizes/classes of hitch for your 2001 Toyota Highlander that you can see on the linked page. Both 1-1/4-inch Class II and 2-inch Class III hitches are offered; I suggest the 2-inch hitch # C13429 from Curt for its no-drill installation and because there are many more accessories made for this hitch size. An installation video and help article are linked for you. For trailer wiring the correct part depends on how the truck was equipped from the factory and what type of connector...
    view full answer...
  • Can Curt Trailer Wiring Harness # C55400 be Used with LED Trailer Taillights
    The Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # C55400 that you referenced works perfectly fine with trailer lights that are LED.
    view full answer...
  • Why Does Curt # C55400 Wiring Harness Require Wire to Battery and Tekonsha # 118413 Does Not
    Some vehicles cannot handle the additional amperage draw of the trailer lights on their taillight circuits, so a wire is required to pull power directly from the battery instead. According to Tekonsha, your vehicle is equipped to handle the extra load, so you would be fine with the Tekonsha T-One Wiring Harness # 118413, especially if you are towing a trailer with just one set of lights at the back and no extra lighting. However, if you are towing a trailer with more than two taillights...
    view full answer...
  • Trailer Wiring Recommendation for 2006 Toyota Highlander to Replace Shorted Harness
    Trailer wiring converter boxes are designed to absorb the shorts in trailer wiring and basically sacrifice themselves to prevent your vehicle wiring from getting damaged. That's what happened in your case. That extra wire you mentioned is used for drawing power for the trailer taillights instead of drawing them from the vehicle lights. This is another way it protects the wiring. The part # 118413 does not use a wire like that. Since I prefer that type of install since it's safer I would...
    view full answer...

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Info for this part was:

Employee Leah B
Edited by:
Leah B
Employee Lindsey S
Written by:
Lindsey S
Employee Jameson C
Expert Research:
Jameson C
Employee Cole B
Installed by:
Cole B
Employee Wilson B
Updated by:
Wilson B
Employee Kristina F
Updated by:
Kristina F
Employee Isabelle B
Updated by:
Isabelle B

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