Tekonsha 118839 T-One 4-Way Flat ModuLite HD
Tekonsha 118839 T-One 4-Way Flat ModuLite HD — Product description
The Tekonsha 118839 is a T-One connector assembly paired with a circuit protected ModuLite HD module and a 4-way flat output. It's a custom-fit way to wire your trailer's running lights, brake lights, and turn signals without cutting into the tow vehicle's factory harness.
If you tow a small utility trailer, a boat trailer, or a pop-up camper, you need clean, reliable lighting at the back of the rig. That's exactly what the Tekonsha 118839 handles. It's a T-One connector assembly that plugs into your vehicle's existing wiring, matched with a circuit protected ModuLite HD module and a 4-way flat trailer plug. No cutting, no splicing, no guessing which wire does what.
Here's what makes the ModuLite HD different from a simple splice-in converter. It's a powered module. Instead of pulling all the current straight through the tow vehicle's light circuits, it draws power directly from the battery and uses your vehicle's signals only as a trigger. That keeps the load off your factory wiring and gives the trailer lights a steady, full-strength feed. The circuit protection built into the module guards against shorts and overloads, so a bad trailer bulb or a pinched wire won't take out your truck's lighting.
The 4-way flat output covers the basics every trailer needs: running lights, left and right turn signals, brake lights, and a ground. It's the most common connector on lighter trailers, so odds are your trailer already wears a matching plug. If it doesn't, a 4-way flat adapter is an easy add.
Because this is a T-One design, it's built to be vehicle-specific. The connectors are shaped to mate with a particular factory harness, which is what lets you skip the splicing. Before you order, confirm part number 118839 fits your year, make, and model. Tekonsha builds different T-One kits for different vehicles, and matching the part number to your rig is the one step you don't want to skip.
It's a solid choice for anyone who wants factory-clean trailer wiring done in an afternoon. Plug the module in, route the 4-way flat to the hitch, and you're ready to hook up and go.
Key Features
- 4-Way Flat output powers trailer running lights, brake lights, left and right turn signals, plus a ground
- Circuit protected ModuLite HD module guards the tow vehicle's wiring against shorts and overloads from the trailer
- Powered converter draws current from the vehicle battery instead of the factory light circuits, giving trailer lights a full-strength feed
- T-One connector plugs into the vehicle's existing harness with no cutting or splicing
- Vehicle-specific custom fit, confirm part 118839 against your year, make, and model before ordering
- Sealed ModuLite HD module built to stand up to road spray and weather under the vehicle
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 | T-One Connector Assembly With Circuit Protected Modulite HD Module; 4-Way Flat |
|---|---|
| Brand | Tekonsha |
| Manufacturer Part Number | 118839 |
| UPC | 016118160888 |
| Connector Style | 4-Way Flat |
| Module | Circuit Protected ModuLite HD |
| Wiring System | Powered T-One converter |
| Power Source | Draws from vehicle battery |
| Circuit Protection | Integrated short and overload protection |
| Fit Type | Vehicle-specific custom fit |
| Installation | Plug-in, no cutting or splicing |
Frequently asked questions
What does the 4-way flat connector power?
The 4-way flat handles the core trailer functions: running/tail lights, left and right turn signals, brake lights, and a ground. It's the standard plug on most lighter trailers like utility, boat, and pop-up trailers.
How is the ModuLite HD different from a basic converter?
It's a powered converter. Rather than running all the trailer's current through your tow vehicle's light circuits, it pulls power directly from the battery and uses the vehicle's signals as triggers. That keeps the load off your factory wiring and gives the trailer lights a steady feed.
Do I have to cut or splice into my vehicle's wiring?
No. The T-One connector is designed to plug into your vehicle's existing factory harness. That's the whole point of the T-One design, no cutting and no splicing.
Does this fit any vehicle?
No, T-One kits are vehicle-specific. The connectors are shaped to mate with a particular factory harness. Confirm that part number 118839 matches your year, make, and model before ordering.
What does circuit protection do here?
The module has built-in protection against shorts and overloads. So if a trailer bulb fails or a wire gets pinched, it won't take out your tow vehicle's lighting.
My trailer has a different plug. Can I still use this?
Yes. The output is a 4-way flat, which is the most common trailer connector. If your trailer uses a different style, an inexpensive 4-way flat adapter lets you connect the two.
