Trailer Wiring Recommendation for 2023 Subaru Solterra

Updated 10/27/2025 | Published 03/06/2025

Question:

I have a small boat and cargo trailer that I plan to tow occasionally with my 2023 Subaru Solterra. I have installed the DrawTite DT46PR trailer hitch and now I need to install the wiring. I see the custom-fit TK84CR wiring harness would work on my Solterra but this requires to be powered via a wire to the battery. Could I instead use the Hopkins HM48915 to avoid a wire to the battery and just splice it into the vehicles taillight harness? How can I tell if that would cause too high of an amp draw? Thank you!

asked by: David B

Expert Reply:

Hey David, on modern vehicles like your 2023 Subaru Solterra it's very common to have to run a power wire up to the vehicle battery to prevent the trailer taillights from drawing from the vehicle taillights. Even if there was a harness that could potentially work on your vehicle that doesn't require that step it wouldn't be ideal as it would blow fuses on the vehicle. So I totally understand it's an extra step that's a pain but it is required and it keeps your vehicle wiring safer. So you would need to use the Tekonsha kit part # TK84CR that you referenced.

expert reply by: Jameson C

Jameson C.

10/27/2025

Hey David, how did things go with wiring the Tekonsha harness on your Solterra? Did running the power wire to the battery work out as expected? Your update could make it easier for the next person setting up trailer wiring on a similar vehicle.

David B.

10/27/2025

Apparently the Tekonsha harness was wired improperly from the factory as other Subaru Solterra and Toyota BZ4X owners have had similar problems with the harness. There was a recent writeup on the Solterra and BZ4X online forums that discuss how to correct the wiring issue.

David B.

10/27/2025

@DavidB a similar harness made by Curt has also had wiring issues.