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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 # C89KR
Our Price: $100.18
You Save: $11.77
Custom Fit Vehicle Wiring

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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 - no cutting, splicing or tapping required. Converter is made using SMT to ensure superior performance. 1-833-496-1390 to order CURT custom fit vehicle wiring part number C89KR or order online at 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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  • Reviews (82)
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  • Why etrailer?

CURT Custom Fit Vehicle Wiring - C89KR

  • Trailer Hitch Wiring
  • 4 Flat
  • Converter
  • CURT

Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. T-connector plugs directly into existing wiring - no cutting, splicing or tapping required. Converter is made using SMT to ensure superior performance.


  • Provides a 4-way flat trailer connector at the back of your vehicle to power your trailer's signal lights
    • Compatible with 5-pole, 6-pole and 7-pole adapters (sold separately)
  • Connects quickly and easily - no cutting or splicing of wires
    • Locate connection points behind tail lights
    • Plug in T-connector
  • Includes a tail light converter to ensure that your vehicle's wiring matches that of your trailer
  • 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
  • Limited 1-year warranty


This custom-fit T-connector plugs into your vehicle's wiring harness.

Once installation is complete, the 4-way connector will be stowed in a secure location.

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.

Tail Light Converter with Surface-Mount Technology

A tail light converter is built into this T-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 the trailer. This converter combines 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.

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.

56442 CURT T-Connector - Surface Mount Technology - 4 Wire

Installation Details C89KR Installation instructions

This Product Fits The Following Vehicles

Customer Satisfaction Score:

Customer Reviews

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - C89KR

Average Customer Rating:  4.8 out of 5 stars   (82 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 - no cutting, splicing or tapping required. Converter is made using SMT to ensure superior performance.


This harness worked perfectly for the 2020 Hyundai Tuscon! The instructions provided by made it easy for a novice like myself to have the confidence to install and it turned out great! I'd recommend them to anyone!


I followed the advice and then video and went and got the kind of connectors that include heat shrink on their ends. Just let me do a perfect job of installing this hardware. But I do highly recommend you look for the YouTube videos that etrailer did on the subject.

2020 Hyundai Tucson

Easy install, love how there’s access to install instructions!


Okay, this was not a 5 minute install, but you knew that before ordering....right?

I should have gotten my SUV up in the air a little better than I did, but I managed to squeeze in where I needed to. I only lifted the back using ramps.

I followed the instructions and example videos and used a trick or two to get this installed (I used a 4' long fiberglass rod to fish up the cable, anything similar would work - fishing pole parts, wood dowel, etc.).

Like I said, wasn't 5 minutes, but in the end I know it was done right and should last. I bought a $4 tester from Harbor Freight and verified the connector was setup correctly (4 connector trailer wiring tester).

I just tested it again, after several months of no use, it's still perfect.

I installed the hitch receiver myself, and this wiring harness myself, and everything is perfect.

Tip, for the hitch receiver put the provided bolts in part way on one side, then use a tie-down strap to hold up that end, while you bolt up the other side. Then you just bolt up the side the tie-down was holding for you and you're 90% done. Hey...if you're on your own you make it work!


This is a great quality product. It was a perfect match for my vehicle. The installer said it was easy to install.


This harness was just too easy to install!
real plug and play. The hardest part was pulling the tail lights out and replacing.
Work great and easily hung on hitch

Kia Soul

Wiring works perfect on Kia Soul LX 2021


Have not installed products at this time, but all look very good. I’ve used Curt Towing Products in the past and the quality has always been 1 class. First time I’ve used etrailer, website is user friendly, order arrived a day early, and was packaged well. Price for items ordered was very reasonable. Called customer support when ordered arrived to verify some information, and support was excellent!!!

So far so good!!!….. I would recommend!!!


I'm not sure what happened but only one side works now. I believe something shorted out and caused the T splice circuit to become fused. I thought the fuse would protect the device from damage but I guess you can't prepared for everything. I'll be ordering a new one at some point but right now no big deal.

You mentioned that only one side is working and I wanted to ask a few questions to help trouble shoot. Have you checked the ground to make sure that it is still a solid ground and has not dislodged? You can also disconnect the power wire to the battery, take the fuse out and wait 30 seconds to a minute and reinstall, then reconnect the power wire. I would also check to see if there is a signal coming out of the black box for all the functions with a tester.
-- Etrailer Expert Jenny N - 07/12/2022


Great product! I received my order within a few days of ordering it. The install was very simple. The longest portion of the install is routing the power wire from the battery to the rear of the vehicle. I used a "fish tape" to help with the task and followed the brake lines for most of the route. The instructions were easy to read and very simple to follow. The connectors fit perfect and within an hour (plenty of water breaks because the of the Oklahoma heat), I had it installed. Works perfect! I would suggest that you have a few more zip ties on hand to helps secure the power wire.

Great job! Perfect company (as usual)!!! Thanks for the quick shipping!

Great product. No issues at all and is still working perfect.
Brent - 07/06/2021


Works fine, plug and play. Really should be 2 self tapping screws in kit.

Hyundai Tucson

Wiring harness was easy to install per the instructions and every part appears to be high quality. Wire lengths provided were much more than enough for the Tucson it was installed in, with several feet to spare for each wire.

Still no issues. Wiring harness continues to function properly.
Michael - 07/20/2021

2019 Hyundai Tucson

Install videos are extremely helpful. Fast shipping and amazing service. I would definitely recommend Etrailer to others.


Fairly easy install but be prepared for some work involved running the power wire up to the battery. I have ramps with platforms, a floor jack and jack stands that were all used so I could remove a protection panel.

2019 Hyundai Tucson

This kit is great! It is designed to take all of the guesswork out of wiring trailer lights, and it delivers. Watch the video and you will be a pro at installing this system. I can't believe how easy eTrailer makes this somewhat mystical installation such a breeze. What a great Company!


EZ install. Works great.


Good quality, great service as always from etrailer. A little more complicated on some Kia models due to needing the power run from the battery, but we had a professional vehicle accessory place so that wire after we did the rest of the effortless initial install, and everything came together just fine.


Gotnhere quick ni fuss what i ordered

2019 Hyundai Tucson

Everything was a perfect fit! Great deal

2019 Hyundai Tucson

I liked the wiring harnesses for easy connection the lights. And even though this needed to be connected to the Positive terminal it was alright.

My only complaint is the module with all of the wiring needs a more secure method of attachment. Mounting tape provided was not sufficient. I ended up making a harness with Pipe Straps.


It was one of the easiest harness to in stall


Everything from ordering, shipping, quality, price and customer service was perfect. Thank you.


Love the fact that there was no cutting or splicing of wires just plug in and it's ready to go. Product showed up in a timely manner along with a follow up telling me the company cares about their customers, I'm glad my fellow coworker told me about trailer.


I finally routed the power to a cigarette plug in the trunk which is switched off when the engine is off so no possibility of draining the battery. Works great.


easy install, everything you need except zip ties to hold up wire to battery, followed break lines. Plugged right in.

Also ordered tow bar from this website.

Show More Reviews

See what our Experts say about this CURT Custom Fit Vehicle Wiring

  • Trailer Wiring Harness For 2020 Kia Soul With LED Lights
    According to Curt the Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector part # C89KR fit all models of the 2020 Kia Soul even with LED lights. This harness will give you a 4-pole flat at the rear of the Kia Soul. I have attached the installation instructions for your reference.
    view full answer...
  • Where Does the Converter Box for Curt Trailer Wiring Harness On a 2020 Kia Seltos Install
    The Curt T-Connector Vehicle Wiring Harness part # C89KR which is a fit for a 2020 Kia Seltos contains a converter box which will mount behind the taillights on the outside of the vehicle. The pigtail with green wire will then be run behind the bumper cover in front of the body panel to the other side.
    view full answer...
  • Trailer Wiring Harness For 2021 Hyundai Tucson Sport
    The good news is I have a solution for you! The only one you need is the Curt T-Connector # C89KR, which is our part number for their harness #56442. It sounds like you've been bombarded with lots of results of similar trailer wiring products. I can certainly understand why it might be both overwhelming and confusing to know which one is best. You listed three t-connector harnesses and one tail-light converter in your list, and two of them are the same part, just with different identifying...
    view full answer...
  • Can 12V Feed For Powered Taillight Converter Be Attached to Power Source Other Than the Battery
    When installing a powered taillight converter like # C89KR, Curt doesn't recommend attaching that 12V power feed to anything other than the positive battery terminal, so I can't recommend anything that would contradict the manufacturer's advice. Drawing the power directly from the battery serves to isolate the tow vehicle's sensitive electronics from any short circuits that might occur in the trailer wiring. Connecting the converter's power feed anywhere other than the battery or where...
    view full answer...
  • Correct Curt Trailer Wiring Harness for a 2023 Kia Seltos
    I was able to confirm that the Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector part # C89KR is correct for a 2023 Kia Seltos (All Models).
    view full answer...
  • Trailer Wiring Kit Compatible With 2021 Kia Soul Without LED Taillights
    The T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # 118813 is a confirmed fit for both 2020 and 2021 Kia Soul without LED taillights.
    view full answer...
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  • Trailer Wiring Harness Recommendation for 2021 Hyundai Tucson with LED Taillights
    The Curt trailer wiring harness part # C89KR is a fit for your 2021 Hyundai Tucson with LED taillights but I would actually recommend the Tekonsha part # 118812 as it has a more reliable converter box.
    view full answer...
  • Install Instructions for Trailer Wiring That Fits 2020 Kia Soul
    You have the universal Curt trailer wiring harness that fits your 2020 Kia Soul with part # C59236 which we do have the easier to install kit part # C89KR which would have been my recommendation for you. But the type of taillights your 2020 Kia Soul has is separate so that would be the set of instructions you should follow in the install instructions that I have attached to this page.
    view full answer...
  • What Wiring Harness Works with My LED Taillights on My 2021 Hyundai Tucson?
    If you want to hook up a trailer with LED taillights to your 2022 Hyundai Tucson, I confirmed with Curt that the Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # C89KR will be compatible with LED-style lights. If you need help with installing the harness, I went ahead and linked a video that walks you through the process. If you need a hitch as well, I recommend the Curt Hitch - 2" # C13240. Not only does the 2-inch receiver allow compatibility with many accessories,...
    view full answer...
  • Recommended Trailer Hitch Receiver for 2021 Kia Seltos
    The trailer hitch I recommend for your 2021 Kia Seltos is the Curt Trailer Hitch Receiver # C65FR. I really like this hitch because its crosstube is concealed behind the bumper, as you can see by the accompanying photo. That means that only the receiver is going to show, which maintains the clean look of your '21 Seltos. I have added a link to the installation instructions for you to check out as well of the Curt Trailer Hitch Receiver # C65FR. Additionally, if you are looking to add...
    view full answer...
    Image 1 for
  • Recommended Trailer Hitch and Wiring Harness for a 2021 Hyundai Tucson
    I was able to confirm with Curt and the Curt Trailer Hitch Receiver part # C13240 has been carried over as a fit for a 2021 Hyundai Tucson. In regards to the trailer wiring, you can use the Curt T-Connector Vehicle Wiring Harness part # C89KR. These are both great bolt-on/plug-in play options that will get you setup and towing in no time. In order to complete your setup, I'd add the etrailer Ball Mount Kit part # 989900.
    view full answer...
  • Difference In Factory Lifestyle Hitch And Frame Mounted Hitch 2021 Kia Seltos
    The biggest difference between a frame mounted hitch and a factory accessory (lifestyle) hitch that is on your 2021 Kia Seltos, is a hitch such as the Curt Trailer Class 1 Hitch Receiver Item # C65FR provides a maximum gross tow rating of up to 2,000 pounds. It also has a tongue weight rating of 200 pounds. The tongue rating is the amount of weight or force that will be loaded downward onto the hitch. Kia states that although the accessory or lifestyle hitch has a tongue weight rating...
    view full answer...
  • Can Hitch for 2020 Kia Soul Transport 300 lb Mobility Scooter
    The problem with hitch adapters is they cut the capacity of the hitch they are installed in by 50 percent and for a lighter duty vehicle like what you have you just don't have the tongue capacity for that. Especially since you want to carry 300 lbs in the carrier. You'd have to use the Curt hitch # C67FR that fits your 2020 Kia Soul to tow a smaller trailer. For wiring you'd then need the part # C89KR.
    view full answer...
  • What Tools are Needed to Install a Curt Trailer Hitch on a 2022 Kia Soul
    Installing the Curt Trailer Hitch Receiver # C67FR on your 2022 Kia Soul is something that I am confident that a moderate DIY person can handle. I have attached a picture from the installation instructions that shows the tools that you will need to accomplish this install. If you will be towing a trailer, the Curt T-Connector Vehicle Wiring Harness # C89KR will provide a 4-way flat trailer connector at the back of your vehicle to power your trailer's signal lights.
    view full answer...
    Image 1 for
  • Replacement Ring Terminal for Curt Trailer Wiring Harness 2019 Hyundai Tucson
    For a replacement ring terminal that came with the Curt trailer wiring kit part # C89KR that you referenced you'd want the # DW05741-1.
    view full answer...
  • Recommended Towing Package For A 2022 Kia Seltos
    When it comes to installing a trailer hitch on your 2022 Kia Seltos I recommend The Curt Trailer Hitch Receiver - Custom Fit - Class I - 1-1/4 inch # C65FR this trailer hitch has a bolt-on installation - with no welding required. It has a gloss black powder coat finish that is over a protective base coat that offers superior rust resistance. The Curt hitch is made in The USA, and has a sleeker look. The trailer hitch has a maximum gross trailer weight up to 2,000 pounds, and has a maximum...
    view full answer...
  • Hitch and Trailer Lights Wiring Harness for 2020 Kia Soul
    We have two hitch options for your 2020 Kia Soul. You can use the Curt # C67FR or the Draw-Tite # DT25GR hitches. They both have a no-drill installation with a 5/10 difficulty but the Draw-Tite requires fascia trimming. I like the Curt's glossier finish. With all that, I would choose the Draw-Tite # DT25GR, hands-down, because is has a 300 pound tongue weight vs the 200 of the Curt, It is a class III hitch vs the class I of the Curt and most importantly, it has a 2" hitch opening vs the...
    view full answer...
  • Hitch and Trailer Lights Wiring Harness for 2022 Kia Soul
    For your 2022 Kia Soul, as long as it's not the 1.6L Turbo model, I highly recommend the Draw-Tite Class III Trailer Hitch # DT25GR. This is because it offers a 2" receiver which will open the door up to many more options when it comes to hitch-mounted accessories like a bike rack or cargo carrier. It's also going to provide a much sturdier attachment point to your trailer. For your lighting needs, I suggest the Curt T-Connector Vehicle Wiring Harness, # C89KR. With this option you can...
    view full answer...
    Image 1 for
  • Parts Needed To Install 7-way Connector and Curt Echo Wireless C51180 On 2012 Kia Sedona
    I would be happy to help! The Curt T-Connector # C56347 and # C89KR you were looking at are both confirmed to fit your 2012 Kia Sedona and will both give you the 4-way connector you need. There is not major difference between the harnesses so I recommend going with the most cost effective option at the time. Moving on to adding a 7-way connector to use the Curt Echo Wireless # C51180 I recommend the # ETBC7L which was designed specifically for the Echo. The # ETBC7L will plug into your...
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  • Recommended Trailer Hitch Receiver For Using a Bike Carrier On a 2022 Kia Soul
    I recommend the Curt Trailer Hitch Receiver # C67FR for your 2022 Kia Soul. This class I receiver is capable of supporting up to 200lbs for your bike rack. The Kuat NV 2.0 Bike Rack # NV12G is a great rack for your mountain bike. It has a built in work stand that allows for you to support the bike easily why you make modifications or repair any damaged components while you are out. The rack only weighs 52lbs and can support 2 bikes up to 60lbs each. Built in locks and cables ensure that...
    view full answer...
  • Recommended Trailer Hitch Receiver And Wiring Harness For a 2022 Kia Soul
    I recommend the Curt Trailer Hitch Receiver # C67FR for your 2022 Kia Soul. If you will be towing a trailer I recommend the Drawbar # 3592 which you will need to attach either a 2" Hitch Ball # 19258 or 1-7/8" Hitch Ball # 19256. The Curt T-Connector Vehicle Wiring Harness # C89KR will connect to the 4-way flat connector on most trailers. It will also allow for you to use Auxiliary Lights # C53201 in the event your hitch mounted accessory blocks the view of your tail lights on your Soul.
    view full answer...
  • Recommended Trailer Wiring Harness and Towing Equipment for 2022 Kia Soul LX
    The Curt # C89KR does carry over for all models of the 2022 model Kia Soul. If you don't already have a hitch, I'd recommend the Curt # C67FR Class I hitch, which fits all Soul models except for those equipped with the 1.6L turbo engine. For a ball mount, use # C45521 along with the # PC2 hitch pin. For a trailer ball, use # 19256 for a 1-7/8 or # 19258 for a 2 inch ball.
    view full answer...
  • Hitch With Highest Available Ground Clearance for 2022 Kia Soul
    As long as your Soul doesn't have the 1.6L turbocharged engine, we do offer a hitch fit from Curt and from Draw-Tite. As you can see from the provided side-by side photo, the Curt # C67FR sits much tighter up against the underside of the bumper than the Draw-Tite # 24985 hitch, so the Curt will provide much better ground clearance. If you'll be doing some light duty towing with the hitch, you'll also need a trailer wiring harness like part # C89KR, a ball mount like # C45521 and a # PC2...
    view full answer...
    Image 1 for
  • Does Trailer Hitch Recevier for 2021 Kia Seltos Require Drilling Into Frame
    No drilling into the frame of your 2021 Kia Seltos is required in order to install the trailer hitch receiver that fits it, the Curt Trailer Hitch Receiver # C65FR. This is a bolt-on installation and uses existing holes in your Kia's frame to install, which is why you don't have to drill. If you plan on doing some light towing with this hitch and your '21 Seltos, there are a few other parts you'll need, which are the following: - Vehicle Wiring Harness # C89KR - Curt Drawbar # C45521 -...
    view full answer...

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Info for this part was:

Employee Mike L
Expert Research:
Mike L
Employee Jameson C
Expert Research:
Jameson C
Employee Lindsey S
Edited by:
Lindsey S
Employee Kathleen M
Installed by:
Kathleen M
Employee Chris R
Video Edited:
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Employee Wilson B
Updated by:
Wilson B
Employee Noah M
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