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T-Connector Vehicle Wiring Harness

T-Connector Vehicle Wiring Harness

Item # C56121

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Our Price: $76.06

Custom Fit Vehicle Wiring

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Custom Fit Vehicle Wiring C56121 - 4 Flat - Curt
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Product Images

In Use/Installed


  • Custom Fit
  • Trailer Hitch Wiring
  • Curt
  • 4 Flat
  • Powered Converter
CURT Circuit Protected T-Connector Vehicle Wiring Harness Call 800-298-8924 to order Curt custom fit vehicle wiring part number C56121 or order online at etrailer.com. Free expert support on all Curt products. Guaranteed Lowest Price and Fastest Shipping for T-Connector Vehicle Wiring Harness. Custom Fit Vehicle Wiring reviews from real customers.


  • All Info
  • Reviews (19)
  • Q & A (2)
  • Videos (2)
  • Photos
  • Why etrailer?

Curt Custom Fit Vehicle Wiring - C56121

CURT Circuit Protected T-Connector Vehicle Wiring Harness


Features:

  • Provides a 4-pole flat trailer connector for the vehicle
  • Installs quickly and easily - simply plugs in to factory connectors
    • Does not require cutting or splicing
  • Includes installation instructions
  • Can be used with 5-pole, 6-pole or 7-pole adapters


Specs:

  • Maximum amperage
    • Stop/Turn lights: 3 amps
    • Tail lights: 6 amps


Installation: Connection point is located behind the driver side tail lights. The 4-pole trailer connector will be stowed in the rear cargo area when not in use.


Tech Tip: It is always a good idea to apply a small amount of grease to all electrical connections to help prevent corrosion.



56121 CURT Circuit Protected T-Connector Vehicle Wiring Harness



C56121 Installation InstructionsInstallation Details C56121 Installation instructions

This Product Fits The Following Vehicles

2011 - 2015 Lincoln MKX

2011 - 2015 Lincoln MKX



California residents: click here


Video of T-Connector Vehicle Wiring Harness


Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Trailer Wiring Harness Installation - 2013 Lincoln MKX

Today on our 2013 Lincoln MKX, we'll be installing the Curt T-connector vehicle wiring harness, part number C56121. Now to begin our install, we'll open up the rear hatch. Then, we'll need to remove the fasteners to secure the rear tail light assembly. There are two fasteners on each side. Once we remove the screws and set them aside, we'll then pop the tail light assembly out of its position being careful not to break the alignment tabs underneath. Next, we'll go ahead and press on the wiring connector lock so that we can remove the wiring harness from the back of the tail light assembly. We will set the tail light assembly aside. Now, we'll go ahead and repeat the same process on the other side.

Now, with both tail light assemblies removed, we'll move to the inside of the vehicle where we'll the remove spare tire cover and then the rear threshold. The rear threshold has fasteners underneath, so we gently pull up until the fasteners released and then remove the threshold completely setting aside. Next, we'll remove plastic trays on either side of the spare tire. We'll set them aside for re-installation later. Next, we'll go ahead, we'll remove the grommet that secures the tail light wiring harness as it passes through the body of the vehicle. Once we pull it out, we can then take the new green wire connector from our new 4-pole harness, feed it up behind the interior panel and out through the open hole from where we removed the grommet.

Then, we'll take a pair of side cutters, cut a slice in the grommet where we can feed the green wire into and reinstall the grommet. Next, plug the green wire connector directly into the manufacturers wiring. The other end will go into the back of the tail light assembly. Next, we'll go ahead and take a zip tie and secure the green wire to the manufacturers wiring. We'll cut off the excess from zip tie to clean up the install look. Now, we're ready to re-install tail light assembly.

Next, we'll begin routing our wiring over to the driver side. This application, we can route it inside the body channel using a pull wire. We'll take the pull wire, route it through the channel first, pulling it over to the driver side. Next, we'll repeat the same process taking the yellow wire connector and feeding it up behind the driver side tail light assembly. We'll cut the slit in the grommet, feeding the wire in.

Then, we'll plug the yellow wire connector into the manufacturers wiring and the other end of T-connector into the tail light assembly. We'll secure the wiring with a zip tie, cut off the excess from zip tie, and then reinstall the driver side tail light assembly. Next, we'll start routing the power wire for our new converter box. This power wire will ultimately get run up to the vehicle battery. We'll go and take the power wire and route it around the second row seat post interior panel to the converter box. We'll strip back the power wire and add the butt connector provided with our install kit. The other end of the butt connector will get secured to the black wire coming from the converter box. Next, we'll go ahead and wrap up this connection point with some black electrical tape to help keep out any dust, dirt, debris, or moisture. Now, with the power wire secured, we'll go ahead and mount the converter box. To mount the converter box, we'll use the two-side adhesive supplied with our install kit. Peel back one side of the adhesive and adhere it to the converter box and then remove the other side of the adhesive and secure it back behind the paneling on the driver side. Note, when you're securing converter box, we're looking for a clean, flat surface, preferably sheet metal. Now, with our converter box mounted, we'll go ahead and take the white wire from the converter box with the pre-attached ring terminal and secure it to the body for the ground for our new converter box and 4-pole connection. Using a self-tapping screw, we'll go ahead and secure the ring terminal directly to the body of the vehicle. Quick check tip: I recommend a final location where the sheet metal doubles up for a more secure ground. Below the tail light assembly near the threshold will be a great location. Now, with our power wire secured to the converter box, we'll go back to the manufacturers grommet and use our utility knife to cut a small slice in the grommet. Then, we can take the other end of our power wire, feed it down through the manufacturers grommet underneath the vehicle. We'll go ahead and pull the excess wire down underneath the vehicle and then secure the power wire to the manufacturers wiring with a zip tie. Now, with our wire fit underneath the vehicle, we can go ahead and route it up through the front of the vehicle at the bottom of the engine compartment. We'll then route up through the engine bay and ultimately to our battery. Keep in mind when routing your wire, stay away from any moving components such as steering or suspension, or excessive heat such as exhaust. Now, we've reached the bottom of the engine bay. We'll go ahead and take our pull wire, feed it up through the engine compartment, and then secure the power wire to the pull wire and pull it up to the top of the engine bay. We'll go ahead and secure it with the black zip ties provided with our install kit. Now, with our power wire pulled into position, we'll go ahead and cut off the excess from the zip ties and clean up our install look and move to the top of the engine compartment. Here, we'll secure the wiring as necessary and route it towards to the positive battery post. We'll go ahead and cut off any excess wire from the power wire so that we can install our inline fuse holder. To do this, we'll strip back the power wire and add a butt connector. We'll take the fuse holder and attach it to the butt connector and a ring terminal to the other end of the fuse holder. We'll go ahead and wrap up this connection point with some black electrical tape and then route the ring terminal to the positive battery post. We'll remove the cover from the positive battery post revealing a positive battery post. We can remove the nut, install the ring terminal, and then re-secure the nut. We'll go ahead and install the fuse into the fuse holder and then secure our fuse holder here to the manufacturers wiring. We'll go ahead and reinstall the positive battery post cover and secure our wiring as necessary with the zip ties. We'll cut off the excess from the zip ties, clean up our install look. We're now ready to test our new 4-pole connector. To test the 4-pole connector, we'll use our test light, taking the ground clamp and putting it on the white wire terminal, which also be the open or bare terminal. Then, testing the brown wire terminal will be our running light circuit, yellow wire terminal will be the left turn signal/left brake, and green wire terminal will be the right turn signal right braking. Now, we know our new 4-pole connector works. Let's go ahead and show you how to use it. We'll simply take the 4-pole connector out of the lower storage compartment and route it out and over the threshold and down to our hitch or accessory. Be careful to stay away from the rear cargo door latch as pinching off in the latch can harm the wire, however, the weather stripping is thick enough having simply close the rear cargo door on it, pull out any wire necessary to run to our hitch or accessory, and then once we're finished, we'll simply open up the rear cargo door and store it down with the spare tire cargo area, and that's it, we're ready to hit the road. That does it for the install of the Curt T-connector vehicle wiring harness with 4-pole flat connection, part number C56121 on our 2013 Lincoln MKX. .


Customer Reviews

T-Connector Vehicle Wiring Harness - C56121

Average Customer Rating:  4.9 out of 5 stars   (19 Customer Reviews)

CURT Circuit Protected T-Connector Vehicle Wiring Harness

- C56121
by:
2011 Lincoln MKX

This product is everything it says it is and the installation was very easy. It was helpful to have an extra person help me feed the electrical wire from the back of the vehicle up to the battery terminal if you don't have a hoist. It came with everything you need to secure the wires and power module including zip ties and wire connectors. 99031


Comments

The wiring harness has not given me a bit of problems after a year of use.

Jeff S - 09/15/2014

6849

- C56121
by:

Came in two days and were able to get it installed before unexpected trip across country . Only issue with install was passenger side light socket, just could not get it to wiggle in, butt spiced wire and it worked fine. Will definitely order again when the need arises. 636917



- C56121
by:

Easy to install and worked correctly. Certainly beat the old fashion way of figuring out which wires to splice into. Well worth the cost to do a plug in factory style installation. 628702



- C56121
by:

Extremely easy and quick to install. Product works great as advertised! 602813



- C56121
by:

Running the wire from the battery to the back was the hardest part. The rest of the wiring was just unplug and replug. I did it quickly with no problem. 550623



- C56121
by:
2012 Lincoln MKX

Hi, the installation was very easy. But I connected the 12V line (fuse 10A) directly to the 12V power line at the liftgate (WH-RD cable, 30A fuse F7 in the battery junction Box). A lot less work. Works fine. 524264


Comments

It is recommended to route the power all the way to the vehicle battery fpr proper fuse and circuit protection. I have included a link to one of our help articles for your reference.

-- Rachael H - 06/20/2018

40022

- C56121
by:
2013 Lincoln MKX

GOOD FAST SERVICE 470199



- C56121
by:

Great product. Youtube video was invaluable. Highly recommended. 457240



- C56121
by:
2012 Lincoln MKX

Great quality product, item exactly as described. Quick shipping, prices are good. Easy to follow instruction videos on the website. I highly recommend etrailer.com for any trailer related needs! Ian, a very satisfied customer 398503



- C56121
by:
2013 Lincoln MKX

Looks great, works great! 387097



- C56121
by:

Late dark night we ran over a blown tire. It went under motorhome & tore up the lights and wires on the tow dolly. etrailer had all the parts I needed, great price & fast shipping. Great group to work with. 362836



- C56121
by:
2011 Lincoln MKX

Excellent product. Installation was easy with the instructions and watching the video. 284160



- C56121
by:
2012 Lincoln MKX

I would give 5 stars as the product itself is excellent. However, if you have the premium stereo with the big rear speaker, you cannot easily fish the passenger side cable to the taillight....the small "tunnel" is slightly narrower at the top than the plugs you are trying to fish up. I finally figured that I had to find a suitable crowbar to bend the inner hole sheet metal to allow the plug to pass. After that, no problems with driver side or with anything else. 259046



- C56121
by:
2013 Lincoln MKX

Product was shipped promptly and price was fair. 255066



- C56121
by:
2013 Lincoln MKX

I have installed 3 Hidden Hitches over the past few years, and have been very well satisfied with the product. 209014



- C56121
by:
2012 Lincoln MKX

Great product. Video helped a lot. Easy installation. 198644



- C56121
by:
Lincoln MKX

Whew!! After recouping from the MKX hitch installation, I tackled the wiring harness. All was straight forward with great instructions and video. The tail light assembly was a tough removal with fears of breaking the guide pins from the light to the body. But with a little patience and finesse they came out as instructed. The toughest part was running the hot wire from the rear to the battery,only because I did not have the availability of a lift. Ramps and a creeper did the trick taking my time to stay away from the heat producing items. Hooked up the trailer and all was a GO! Great product thus far. 193862



- C56121
by:
2012 Lincoln MKX

Great product! Super fast FREE shipping. Exactly what I ordered and it fits exactly how it is supposed too. 157430



- C56121
by:
2011 Lincoln MKX

Great product. Easy to install. 83119


19
19

Ask the Experts about this Curt Custom Fit Vehicle Wiring
Do you have a question about this Custom Fit Vehicle Wiring?


  • Trailer Wiring Harness Options for a 2011 Lincoln MKX
  • Curt trailer wiring harness # C56121 does indeed fit your 2011 Lincoln MKX. Installation will be the same as the video I have linked which features a 2013 MKX. We also have Tekonsha harness # 118519 or Hopkins harness # HM11140314 which also fit your MKX. They all install and function in the same manner but we do hear about fewer issues with the Tekonsha harness.
    view full answer...

  • Does Wiring Harness for 2011 Lincoln MKX Work With Trailer That has LED and Incandescent Lights
  • Yes, the T-Connector Vehicle Wiring Harness # C56121 that fits your 2011 Lincoln MKX will work if your trailer has LED lights and incandescent lights so long as your lights do not exceed the maximum of 3 amps for the stop and turn signals and 6 amps for the tail lights. It is also highly recommended you use Dielectric Grease # 11755 when using your 4-way to help prevent corrosion. I have added a link to a video review of this part as well as a link to a video install of this harness...
    view full answer...


Do you have a question about this Custom Fit Vehicle Wiring?




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Info for this part was:

Photos by:
Theodore B
Expert Research:
Michael H
Video Edited:
Joshua S
Test Fit:
Nicholas E
Installed by:
Cole B
Photos by:
Zach O
Updated by:
Sarah W
Updated by:
Kristina F

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