T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
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2003 Saab 9-5
These items fit your vehicle
2003 Saab 9-5
Arrives before Christmas To see if this custom-fit item will work for you please tell us what vehicle you'll use it with.
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Quickly and easily install a 4-way trailer connector on your vehicle with this custom wiring harness. T-One connector plugs directly into existing wiring. Powered ModuLite reduces strain on wiring system.
Features:
Specs:
Installation
This custom-fit T-One connector plugs into your vehicle's wiring harness, which is located inside your trunk, behind the tail lights on both the driver's side and passenger's side. You will need to remove some interior trim or carpeting to access the harness. Once you've plugged in the T-connector, run the hot lead up to your car battery. Connect the lead to the included fuse holder, and then connect the fuse holder to the positive terminal on your battery and insert the provided fuse.
Once installation is complete, the 4-way flat connector will be stowed within your trunk.
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.
A ModuLite power module is built into this T-One 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 your trailer. This power module functions as a tail light converter to combine 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.
With a ModuLite, your trailer's lights will be powered without overloading your vehicle's electrical system. Because the module draws power directly from your car's battery and bypasses the electrical routes that are used by a basic wiring harness, there is virtually no draw on your tail light circuits.
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Went on as instructions showed.
everything plugged together perfectly, all the connectors & wiring of high quality and long enough to route neatly.
I didn't have to cut any wires. It's plugnplay Trailer lights harness what could be better?
Package showed up in 2 days as I was told. No damage.
Ordered on line and would have preferred to talk to an agent to make sure that I was buying the correct hitch.
Brooke M.
4/28/2025
We are happy to help if you ever need to reach out about anything else in the future! We have email, chat, and folks on the phones ready to go :)
Product was easey to instal, directions were clear and the quality of the product is very good.
Complete kit for the DTS!
Seemed expensive, but was complicated to make the old style trailer lights work with the new low power LED lights that don't use the same circuit for brakes and turn signals like the old cars did. The instructions worked, and all of the components were there and plugged in like they said it would . I just use the trailer occasionally, so i just leave the "pigtail" in the trunk until i need it.
I was very pleased with the harness. The directions were easy to follow. There was a ground wire right next to where I mounted the black box so I didn't have to drill a ground hole. Very Pleased. Thank You
Mike
1/28/2014
I could not be happier with e-trailer. The harness plugged right in and worked perfectly. Great product from a great company.
Item better than described and super easy to install. I highly recommend this kit.
Completely satisfied with the trailer hitch. The installation was much easier than I expected, and the engineering thought behind the installation was remarkable. I especially liked the spring like feature on the mounting bolts to help guide the bolts into the proper location on the vehicle. Good Job!
Slightly more involved than your basic pigtail but the installation video helped tremendously. The only nit I had was that the ground wire for the power unit could stand to be a little longer. Very satisfied.
The website is super easy to use. Terrific [online] how-to videos brought me to the site. I’ve never come across a more efficient online buying experience. Two things could be improved: one, the how-to video covered an earlier model than my car, and I had to figure out some differences for my particular application on my own, which took me awhile. Second - and this is a fault with the manufacturer, not the seller - the tongue offered with the trailer hitch was a poor fit for my car. It needs to be redesigned. It will give me some problems that I shouldn’t have to deal with on a model/specific fit.
I g ot the hitch for my cad. and it fit up under the car very satisfactry
The wiring was simple but putting the hitch and the wiring was aq litle time consuming for me as a amerture i was a little slow getting it on.
I do like the way it fits and everthing
THanks Richard Walker
The etrailer.com group did a great job getting me the correct hitch and wiring kit in a timely manner.
The product fit perfectly!
Thank you etrailer.com
Fit and installation were and are a piece of cake. Working great after more than a year !
James S.
1/29/2018
Super, I trailer my Harley to Daytona Beach Fla. every year. Easy connect easy stow when not in use.
WIRING HARNESS WENT IN WITHOUT A PROBLEM. ONLY CHALLENGE WAS ROUTING THE HOT WIRE TO THE BATTERY UNDER THE REAR SEAT. INSTRUCTIONS WERE VERY GOOD AND EASY TO FOLLOW.
The Tekonsha wiring kit is well constructed and etrailer has good pricing and fast shipping. I recommend this product.
Wire set arrived very quickly. The it was exactly what I wanted to make the installation easy when compared to other wiring kits
The installation videos make this easy to install, and made the sale for me. Just terrific and specific to my car.
wire a little to short from black box to driver side connecter. Longer on you tube vid. difficulty mounting box. need tacker.
Young man named Jesse took my order. He was very upbeat, knowledgeable, thorough, polite and helpful. I have done business with your company before and it is always a pleasure The items were received timely and in good condition. You're a great company... Keep it up.
Product is great UPS on the other hand dropped it at a different location had to go look for it after I noticed it was delivered and I did not have it. I will order again your service is very fast not your fault for UPS.
Works great and easy to understand instructions
My only complaint is that instructions need be a little more detailed for those of us that have never installed this product before!
Perfect fit. Wiring diagram and instructions were clear on what to do..
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Brooke M.
3/17/2025
Yes! Love it when its designed to be simple and it is. [whispers] It's none of my business, but what are you using a trailer wiring harness for on a Caddy DTS?