Can Hopkins Trailer Wiring Use 12 V Accy Circuit for Power Wire instead of Battery
Updated 09/29/2025 | Published 09/08/2025
Question:
Question about the HOPKINS wiring harness for a 2010 Volvo V70. Can I run power from the 12volt power outlet in the rear of the car rather then running a wire to the battery? Thank you.
asked by: Alan K
Expert Reply:
Hey Alan, if you were to run the power wire of the Hopkins trailer wiring part # HM11143735 to the 12 volt power outlet it would probably work in the short term but if you were to have a short on the trailer wiring it would potentially damage that circuit. The reason it needs to run to the battery so that all of your vehicle wiring circuits are protected.
Product Page this Question was Asked From
Hopkins Plug-In Simple 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
- Hopkins
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Jameson C.
9/29/2025
Hey Alan, did you decide to run the power wire to the battery for your Hopkins wiring harness? I'm asking because your experience could help others who are considering similar setups.