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Tired of dealing with complicated installations? The Tekonsha OEM Replacement Vehicle Wiring Harness provides a custom-fit T-One connector that plugs directly into your vehicle's wiring harness. Located in your vehicle's rear cargo area, this seamless connection makes installation straightforward. Simply remove the access panel doors, plug in, and run the body harness to your car battery - no hardwiring required.
Worried about overloading your car’s electrical system? The ModuLite powered tail light converter incorporated in this harness reduces the strain on your vehicle's wiring system. This feature combines your vehicle's brake and turn signals for compatibility with your trailer lighting setup without affecting your car’s operations. It draws power directly from your car's battery, ensuring that your trailer lights are powered safely and effectively.
The included brake controller adapter makes connecting your electric brake controller a breeze. Designed to plug into your vehicle’s built-in brake control wiring harness near the steering column, it demands no additional wiring – making the installation non-permanent and flexible, allowing for easy removal of the brake controller whenever needed.
Match made in towing heaven? This harness is fully compatible with an extensive range of proportional and time-delayed brake controllers, including the popular Tekonsha Prodigy P2 (#90885) and P3 (#90195) models. These are known for their effective and easy-to-set-up brake control, enhancing your towing experience with superior comfort and control.
With a maximum amperage of 4.2 amps per circuit for stop/turn lights and 7.5 amps per circuit for tail lights, this harness is built to handle the demands of your trailer’s electrical systems. Secure your peace of mind with a 1-year limited warranty, assuring you of its quality and durability over time.
Looking for an all-in-one wiring solution for your trailer? This harness features a complete 7-way, RV-style trailer connector that allows your vehicle to power all the signal lights on your trailer. No converter is needed, and the 7-round blade design is perfectly tailored for your towing needs, ensuring that all your signals are seamlessly integrated and operational.
This will not affect how the tail lights on your vehicle operate.
California residents: click here
The trailer wiring harness didn’t work. After the hour or so to install it, and then driving an hour and a half to pick up my new trailer, that’s when I found out the trailer lights wouldn’t work. The guys there tested everything and said my harness was the problem. After talking to etrailer, they said it sometimes happens and I would have to send them the one I installed back to them before they would send me another. I ripped out the old one bought a new one from my local NAPA and haven’t had a problem. It’s unfortunate because I’ve bought from etrailer before with no issues, But Never Again.
Very easy to install. The hardest part was connection to the battery and brake wire. The only thing I'd like to see added is in-line connection to brake pedal like the taillights. I'm not crazy about wire taps, they can cause nightmares down the road.
Quality parts, all hardware included to make for simple installation from start to finish.
I purchased the wiring kit, brake controller and extra bracket for my 2016 Promaster 118. The install went great. I used another stainless steel bracket to attach the 7 way to the bumper cover. It looks good and totally professional. The brake controller sits just below the fuse box and is out of the way but accessible. I did route my power wires going to the front beneath the van. I drilled a 1/2 inch hole through the rear plastic of the battery box to bring those wires in.
Works perfect
Works great installed 6 on a fleet of p romasters.
Would rate this higher but the instructions are lacking key detail about tapping into the brake pedal wire which is absolutely critical for this to work properly. There is a small red wire that comes off the brake control harness. in the instructions it simply says "connect to negative side of brake switch". which is totally vague and it gives no further details or photos. I had to do some online research work to find out you need to tap into the green and white wire that is above the brake pedal in a factory 4 wire harness. its all the way on the end. connect the red wire to that wire and you are good to go. This should've been explained better in the instructions that come with it as it took a lot of time and headache to figure out on my own.
PLUGS NOT ALL CORRECT. SHOULD HAVE A 4TH WIRE FOR THE BRAKE SUPPLY VOLTAGE FROM THE REAR WITH OTHER WIRES.
Kate F.
9/24/2025
I am sorry to hear that the wiring was not correct T. Can you please confirm the year, make, and model you were installing this on so I can see why it didn't work.
YES...YES...YES...My Ram Promaster 1500 did not have factory installed Trailer light system. I contacted a nationally recognized trailer/hitch company to install my system and after 7 hours of my wasted time/money, they failed to do it correctly. I had used a similar product to this in the past and it worked well so I ordered this one as I upgraded to electronic brake controller. Came with EVERYTHING needed. Complete instructions. PERFECT PRODUCT...PLUG AND PLAY...Just make sure you order the correct one for your application (4 pin, 5 pin, 7pin) and adapters if needed. I operate in harsh environments of heat, cold, dust, off road... so I also use the dielectric grease on all connections . Wires are also protected by secondary abrasion protection outer wrap...Does not get any better than this. Dont buy cheap knock off wires at your local auto store...do it right, your pulling valuable equipment and have a responsibility to tow safely.
This is one of the easiest trailer brake & trailer light wiring kits to install. The plug and play connectors makes it a breeze. The video provided matches what you actually have todo identically which made it even better. I was two connectors short but other than that everything I needed was provided!
Good product. Has held up. I had two Curt wiring harnesses fail before installing this one. It's been good through two winters.
This is the second set of Hitch, wires, and controls. Super easy just as advertised. They come in a reasonable amount of time and always in good condition. I recommend them to friends because I have had a great experience.
Extremely Easy install thanks to the great instructions.
Highly recommend etrailer.com
Great wiring easy to install and route glad to have videos for any possible issues wish the hitch fit better had to grind down bumper sides in order to get it to fit properly other then that all was as good as I can expect from eteailers good quality and fast reliable products
Nice products and has worked out very well. etrailer is a good supplier.
Fits perfectly and the video of the installation was very helpful.
etrailer beat competitors pricing and the product arrived very quickly! Great customer service!
Thank you etrailer!
Everything went perfect from ordering to installation
This was easy to install and the length was perfect. It did come short one ring terminal--you will need 4 and it only came with 3.
Just received and not installed yet but in unpacking the harness it feels quality and is/ was a great price for all it does.
A+++ fast shipping
Great product fast shipping Thank you
Fast delivery great customer service
The website is easy to look at and explains what you need to know. The delivery took some time but it was because we were waiting on one of the parts. Someone emailed me and offered a different product so that we could get our delivery faster. We didn't need the parts that fast so we just waited for the original part. Overall a great experience.
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Mark B.
10/4/2017
One year later everything is fine.