4-Way and 7-Way Recommendation for 2015 Toyota Sienna LE

Updated 11/03/2025 | Published 09/28/2025

Products Featured in This Question

Adapter 4-Pole to 7-Pole and 4-Pole

(659)

$61.47

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(265)

$86.00

Curt Trailer Connector Adapter - 4-Way to 7-Way RV and 4-Way Flat

(472)

$34.94

Question:

Hello, I have a 2015 Toyota Sienna LE AWD and need a 4-pole flat wiring harness along with a 4-to-7-way adapter. From what I have read, the Tekonsha 118648 harness and Curt C57672 adapter is what I need. Does this sound correct to you? Thanks, Brad C57672 118648

asked by: Brad D

Expert Reply:

Hey Brad, the Tekonsha 4-way kit part # 118648 is the correct fit and best option for your 2015 Toyota Sienna LE. Then for a 7-way adapter the part # C57672 that you referenced would be exactly what you'd want as well. Does the trailer have brakes?

I noticed you also referenced the # 37185 7-way adapter which is also a really great option just like the Curt but it does look like it costs more so it wouldn't be what I would go with if I were you.

expert reply by: Jameson C

Brad D.

10/1/2025

Yes, the trailer has eBrakes. I have been looking at the Curt C51180 proportional controller. This might be a solution for my application. What are your thoughts? Thanks-Brad

Jameson C.

10/1/2025

@BradD If you wanted to use the Echo # C51180 the 7-way adapter you'd need instead is the part # ETBC7L which comes with the additional wiring needed to power the Echo beyond just the adapter. Some people have great luck with the Echo and when it works well it's really pretty cool since it's such an easy to install and use controller.

Brad D.

10/6/2025

@JamesonC The Tekonsha 4-way kit part # 118648 looks to have a direct connection to the 12V battery using supplied wiring. Will I need to run another 12V wire (as supplied in ETBC7L) to the battery to power the ECHO, or will the same power wire work?

Jameson C.

10/6/2025

@BradD You do want to run the separate wire for that. The brake controller needs it's own dedicated power wire and if you tried to use the 4-way kits power wire you'd end up shorting out the trailer wiring. If you wanted to run both power wires at the same time you could use the part # 10-2-1 which is two 10 gauge wires jacketed together that you could use so that you run "one" power wire but at same time you get two to the same area.