Why Does Trailer Wiring Require Power Wire Ran to Vehicle Battery

Question:

there is a 12v outlet in rear cargo. Can that be used to power controller rather than direct to battery?

asked by: Davin H

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.

If you were to instead draw the power from the outlet you mentioned you would be bypassing the circuit protection mentioned and it would void the warranty.

expert reply by: Jameson C