Why Do Some Trailer Wiring Harnesses Have Wire that Runs to Vehicle Battery
Published 10/04/2018
Question:
Hi. I am planning to tow a trailer without any brake. Do I need to connect the wire from the trailer wiring harness to the cars battery for the running, signal, and brake lights to work? Thank you.
asked by: VP
Helpful Expert Reply:
Not all vehicles can handle the additional amperage draw of the trailer taillights on the vehicle taillight circuits. Those vehicles need setup that draws power from the battery. Some vehicles have higher rated circuits that can handle this, and others need to have the power drawn straight from the battery to protect the taillight circuits. So the connection has to be made to the vehicle battery otherwise the harness will not work.
That said, if you have a 2005 Toyota Matrix like you referenced the Curt trailer wiring harness part # C55522 does not require a power wire ran to the battery.
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
- Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Hidden
- CURT
more information >
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