Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
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2003 Lincoln Aviator
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2003 Lincoln Aviator
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Trailer lights can overload delicate vehicle wiring if power is pulled directly from the taillight circuits. This harness uses a powered converter that draws power straight from the vehicle battery instead. It keeps the electrical system safe from overloads or short circuits while still powering the trailer lights reliably.
Instead of stripping wires or chasing circuits, the T-Connector simply plugs into the factory tail light connectors. Once connected, you just run the single hot lead to the battery. The plug-in design keeps things clean and lets you hook up a 4-flat trailer connector without altering the factory wiring.
This harness works with both standard incandescent and LED trailer lights. The built-in converter ensures proper signal flow and voltage, so your trailer lighting functions as expected no matter what bulb type it uses.
The flat 4-way plug can be routed outside near the hitch or stored inside when not in use. That keeps it out of the weather and away from damage when you’re not towing, giving you a clean look and longer-lasting connections.
Customer Satisfaction Score:
96% were satisfied with this product
4% of customers were not satisfied
Ratings & Reviews
As good as the product itself are the videos available pertaining to the installation of the product and related items. I viewed them all. Excellent subject matter with complete instructions.
Great product. Etrailer has wonderful customer service and I love the video review/demonstrations a lot of their products have as well.
Easy to install. The etrailer product video was extremely helpful for me, since I have limited experience with wiring.
This harness was purchased for my grandsons vehicle. As far as know it has worked great. As far as installation ? He installed it. I didn't hear any complaints.
Great products !!!!!
The wiring kit was a breeze. If your mechanically inclined it should be easy for you. The instructions are clear, shipping is fast and the website layout is great. Good job etrailer.
Everything arrived on time and well packaged. The wiring install went exactly as described in both the written and video instructions. The main reason I purchased from etrailer.com was the quality of the information on the products and installation. Couldn't be happier with the process from beginning to end. And the new hitch and wiring looks and works great!
I purchased the hitch bracket and the wiring harness for a Mazda CX5. Was very satisfied with the quality of the product. Both packages were complete without parts missing. Installation went very smoothly, recommend two people to install the hitch as it is cumbersome trying to hold it in position and start the nuts on the bolts. Very satisfied with the end result.
This is the third hitch that I have purchased from etrailer.com. All have been exactly as ordered and, although I have not had time to install the new hitch, I am certain it will fit. The detailed installation instructions and online videos make it impossible not to do it correctly and easily. The same goes for the wiring harness that I ordered. I have never installed one before but, after watching the video, it looks like a piece of cake.
Fit and works perfectly
The module in my original Curt wiring harness went bad after 3 years which was a real disappointment as I hate installing these things. Didn't have much choice, so I ripped my interior apart (again) to remove the old module/harness and install the new one. It would have been easier if the harness plugged into the module, so that just the module could be swapped out, but everything is hardwired. A few hours later the job was done. I like that the harness plugs right into the existing tail light connectors: no splicing into car's wiring harness. I did not run a new wire to the battery and just spliced into the existing one from the original install.
The instructional video from eTrailer was great and they are a pleasure to do business with. I'm still annoyed the original module went bad, but life happens.
We were very pleased with our order from etrailer (hitch receiver + wiring). They took the time to ensure the wiring harness didn't rattle around in the package with the receiver and filled our order in record time. While we will be only using it occasionally, having an easy to install tow package will help us move those bulky loads with ease. Thanks etrailer!
Product works and instructions were pretty good. Instructions could have been a little better on some points: 1) Routing power wire to the battery could use a suggested route. 2) No mention of the access panels that are available on 2016 CX-5, which makes getting to the rear light sockets a breeze. 3) Suggest a good place to attach the control module so the harness doesn't end up too short to reach the hitch area.
I found a YouTube video that filled in the gaps.
Product was as expected and as described. Easy to install. Used to tow a utility trailer by Jeep Cherokee, a alwn mower at times and was used once to haul load of furniture in my son's move. Would recommend it to persons needing an after market towins setup.
I've had this on my Mazda CX-5 for the past year, I've used it numerous times, hauling one dirtbike on a hitch carrier, hauling multiple large motorcycles on a Kendon Motorcycle Trailer, and also using my No-Mar tire changer on it as well. It's been super durable and problem free. Hoping for many more years of quality use out of it.
Fix perfectly, but I ran the power cord inside instead of following the instructions. It fit under the trim and there was a “spare” grommet to run it through the firewall. Overall I’m very happy with the whole transaction! Thanks again etrailer!
Gord
4/2/2019
No issues, I’m happy! I kept all the wiring inside so it doesn’t get exposed to snow and salt.
The wiring harness fits perfectly, and was super easy to install. I have no complaints, and the team at etrailer.com were great to work with, super fast service!
Jeffrey D.
11/2/2018
Fantastic, no issues!
Perfect, no issues installing this harness. Plenty of wire and the connections make it hard to do wrong. Nothing to splice or cut, just unplug your taillights and connect the harness.
One year review. Great buying experience. Very easy install, clear instructions, and great video explaining the steps. No complaints. Works as intended. I tapped into 12volt accessory plug in trunk; etraier doesn’t recommend because of safety reasons. Their logic made sense; I had my reasons. I don’t recommend it for others unless you know what you’re doing.
* Wiring harness works great, no problems so far after 1 year.
* Easy to install if wiring doesn't scare you. Plug and play makes it simple. I elected not to run the 12V line all the way from the trunk to the battery so I connected the 12V line to a cigarette lighter plug and then plug this into my accessory port located in the rear cargo area. I dont use the trailer all that often so simply plugging/unplugging this cigarette lighter in each time is no big deal. The CX-5 cargo area accessory socket is already fused for 15A so there should be no problem with the LED trailer lights I'm running.
* I have purchased several CURT trailer hitches and wiring harnesses over the past several years and have been very pleased.
* etrailer has also been very easy and professional to work with. Their website is outstanding with videos and instructions to review items before you buy to see what the installation will entail. I wish other websites were as thorough.
*Wont hesitate to buy again from etrailer.
This is a replacement for my previous Curt harness / adapter, which developed an intermittent fault in the running lights after several years of use. After troubleshooting I concluded the fault was interior to the module, which is sealed and not possible or practical to repair--so I replaced it.
Paul
5/15/2023
This replacement developed the same intermittent fault in the running lights almost immediately. Purchased a different brand, can’t recommend at this point.
This is a true plug and play adapter for your trailer lights. It takes more time to remove the panels than it does to install the adapter. It works with my 2016.5 CX-5 that has partial LED lighting. Power is available in the rear from the 12V power outlet that is always hot and has a 15A fuse. There is a body ground behind the left tail light, just perfectly placed. Below and behind the left tail light is a flat spot and a natural place to put the control box. DON'T use it; the trim panel will not fit with the box there. Tuck the control box behind a flange just to the rear of that perfect place for the box.
John
8/28/2018
Not much to say after a year. It works great! Has not caused any problems with the tail lights or car. Perfect as can be.
I purchased the wiring harness along with a 2" hitch, as well as a Hollywood Racks bike rack. The videos for all three items made the installations easy. I purchased the hitch shortly after purchasing a Mazda CX-5, primarily for use with a bike rack. I went ahead and purchased/installed the harness at the same time so that if and when I need it for towing, I'm ready to go. This harness, slaving off the battery for power directly, versus the lights, made sense - brighter, no concerns of blowing fuses, etc.
On a side note, I really like my Hollywood Racks bike rack - it holds bike snug, it's secure, it's easy to mount, and best of all, I can switch from a two bike mount to 4 bikes in maybe 5 minutes.
Eric
6/11/2018
I haven’t actually used the wiring harness as of it, so nothings changed as far as my review goes. That said, we moved to Germany later last year, and trailer lighting requirements including bike racks that reduce visibility of rear tail lights and license plate require lights and plates be attached to those extensions. Bike racks available here now only come with lights and room to attach a plate, but the hitches are different. SO, I will be purchasing some trail tail lights and a harness soon and building a basic light and license plate board that I’ll hang attach to the bike rack I also purchased. I’ll be sure to seek help as necessary, and intend to purchase from etrailer. Will be in touch.
Rachael H.
6/12/2018
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After gathering my tools up and setting my timer it took me 90 minutes to get this job all buttoned up. The instructions were clearly written with good pictures. I would add a wire fishing tool to the recommended tools list though.
I bought the C56310 trailer hitch and the recommended wiring harness for my 2016 Maxda CX 5. I jacked the back of my car up and installed it in my garage. Everything went together smoothly with no issues. Between the hitch and wiring it took under two hours. My local trailer place wanted almost $600 for the hitch wiring and installation. I spent $**. Excellent support videos and online support. Quality product.
Bill. M.
7/20/2017
I use my hitch weekly for towing my boat. I have had zero issues. Everything was easy to install and works perfectly. I have not seen a factory installed hitch on a Mazda CX-5 so when others see it they ask me where I got it and I always recommend ETRAILER.
It was easy to set up and it has been working like a charm. The printed instructions and the videos were very helpful and clear. A very good improvement from the older I had on my trailer, no doubt.
Maurizio
5/8/2026
It is still working like a charm. No issues whatsoever. Thank you.
Gwendolyn Y.
5/8/2026
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Lanier
6/7/2021
Continues to work well with no problems.