Can a 4-Way be Added to Trailer Wiring for Light Bar on Boat
Updated 01/19/2026 | Published 12/18/2025
Products Featured in This Question
Question:
Want to add a brake light bar on top of my boat for trailering. Wish to keep existing trailer lights working. Need a Y-adapter to the existing wiring of some sort to add the light bar wiring. Do you have any product recommendations.
asked by: Patrick B
Expert Reply:
Hey Patrick, basically you would need to splice in an additional 4-way to the trailer's wiring so that your light bar can be powered. Easiest way to do that would be with a kit like the part # C58044 which you'd splice into the current trailer's taillight circuits. This will give you a 4-way for a light bar to plug into like the part # OPT65KB. How were you planning on attaching the light bar to the boat?
Product Page this Question was Asked From
Curt 4-Way Flat Trailer Connector w/ 60" Harness and Wire Taps
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- No Converter
- Universal Fit
- 4 Flat
- Plug and Lead
- Splice-In
- CURT
more information >
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on Custom Fit Vehicle Wiring
Jameson C.
1/19/2026
Hey Patrick, how did things go with adding the light bar to your boat using the 4-way splice kit? Your setup could be really helpful for others wanting to keep their trailer lights working too.