Tekonsha 118449 T-One 4-Way Flat Wiring Harness
Tekonsha 118449 T-One 4-Way Flat Wiring Harness — Product description
The Tekonsha 118449 is a T-One connector harness that gives your tow vehicle a clean 4-way flat trailer plug. It plugs into the factory wiring behind your taillights, so there's no cutting or splicing, and it terminates in the flat connector a basic trailer needs.
The Tekonsha 118449 is a T-One connector wiring harness that gives your tow vehicle a factory-clean 4-way flat trailer plug. It's built to replace the OEM wiring harness and tap into your vehicle's existing lighting circuits without cutting a single wire.
Here's how it works. The T-One connector plugs right into the factory wiring behind your taillight or at the harness junction, and the vehicle's original connector plugs back into the other side. No splicing, no scotch-locks, no guessing which wire is the left turn signal. You route the 4-way flat out to the hitch and you're wired for trailer lights.
The 4-flat carries the four circuits a basic trailer needs: running lights, left turn and brake, right turn and brake, and a ground. That covers most small utility trailers, landscape trailers, and lighter boat trailers that don't run electric brakes. If your trailer has surge brakes or no brakes at all, a 4-flat is exactly what you want.
Why go the plug-in route instead of splicing into the harness? Two reasons. First, it's faster. Most installs take a few minutes once you've found the factory connector. Second, it keeps your factory wiring intact, so there's nothing to corrode or work loose down the road, and nothing that'll trip up a dealer if you ever need warranty work on the vehicle's lighting.
This is the genuine Tekonsha part, not a generic copy, so the connector housing and pin layout match the factory plug exactly. That's what makes the fit clean instead of fiddly.
One thing to check before you order. This is a vehicle-specific harness, so the 118449 is cut for a particular range of years, makes, and models. Confirm it matches your vehicle before buying. And because a 4-flat has no dedicated brake-output or reverse circuit, it won't run a trailer with electric brakes on its own. If that's your setup, you'll want a brake controller and a different connector. Not sure which way to go? We'll help you sort it out.
Key Features
- T-One connector plugs directly into the factory wiring, no cutting or splicing required
- 4-way flat trailer connector carries running lights, left and right turn and brake, and ground
- Direct replacement for the OEM wiring harness, vehicle-specific custom fit
- Genuine Tekonsha part with a connector housing and pin layout matched to the factory plug
- Ideal for small utility, landscape, and light boat trailers without electric brakes
- Fast install that keeps your vehicle's factory wiring intact
Why Buy from NVN Marine
- Authorized Tekonsha reseller, full manufacturer warranty
- NMEA member and ABYC certified, advice from real boat techs
- Same-day shipping before 3 PM ET on in-stock items
- NY headquarters and Fort Lauderdale flagship retail store
Technical specifications
| Title | 4-Way Flat Replacement For OEM Wiring Harness |
|---|---|
| Brand | Tekonsha |
| Manufacturer Part Number | 118449 |
| UPC | 016118063097 |
| Connector Type | T-One Connector |
| Trailer-Side Connector | 4-Way Flat |
| Function | OEM wiring harness replacement |
| Installation | Plug-in, no cutting or splicing |
Frequently asked questions
Does this harness require cutting or splicing into my wiring?
No. The T-One connector plugs into your factory wiring and the original vehicle connector plugs back into the other side. There's no cutting, no scotch-locks, and no wire-testing to find the right circuits.
What does a 4-way flat connector carry?
Four circuits: running lights, left turn and brake, right turn and brake, and a ground. It does not carry a dedicated brake-output or reverse circuit, so it's meant for trailers without electric brakes.
Will the 118449 fit my vehicle?
This is a vehicle-specific harness cut for a particular range of years, makes, and models. Confirm the 118449 matches your vehicle before ordering. If you're not sure, send us your year, make, and model and we'll check.
Can I tow a trailer with electric brakes using this?
Not on its own. A 4-way flat has no brake-output circuit. If your trailer runs electric brakes you'll need a brake controller and a connector with more pins. We can point you to the right setup.
Is this a genuine Tekonsha part?
Yes. It's the genuine Tekonsha 118449, so the connector housing and pin layout match the factory plug exactly for a clean plug-in fit.
Do I need special tools to install it?
Basic hand tools are usually all it takes. Most of the job is finding the factory connector, unplugging it, and inserting the T-One harness in between.
