Does Curt Trailer Wiring Harness # C45FV Have to Run Power Wire to Battery
Updated 01/19/2026 | Published 08/12/2024
Question:
Hello there, If I have a 12v power outlet in the trunk, can I connect the power to it rather than long haul the wire to the battery on C45FV harness? Thank you in advance, Boris
asked by: Boris Z
Expert Reply:
Hey Boris, so while I totally get the temptation to run the power wire of the Curt kit part # C45FV to an easier to access source you really do have to run it up to the vehicle battery if you want it to actually serve it's purpose as circuit protection.
What this does is use your vehicle signal lights as signal circuits but actually draws power for the taillights from the vehicle battery instead which means that in the event of a trailer wiring short you wouldn't have to worry about the vehicle taillight circuits getting damaged.
Product Page this Question was Asked From
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Powered Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Hidden
- CURT
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Jameson C.
1/19/2026
Hey Boris, how did things go with running the power wire for your Curt wiring harness up to the battery? Your results could really help others who are thinking about the same setup.