Do I Need a License Plate Extension Harness?

Published 10/09/2026

Products Featured in This Question

Tail Light Extender for Light & License Plate Kit for Thule Verse Bike Racks

$34.95

Tail Light Kit and License Plate Holder for Thule Verse and Vero Bike Racks

(1)

$254.57

Thule Verse Bike Rack for 4 Bikes - 2" Hitches - Wheel Mount

(5)

$1699.90

TowSmart 4-Way Flat to 4-Way Flat Trailer Wiring Harness Extension Kit - 18" Long

(14)

$7.91

Question:

Is this needed for 2017 Toyota Sienna LTD ?

asked by: Zak

Expert Reply:

Hey Zak!

You may need the Thule Tail Light Extender # TH57SA for your 2017 Toyota Sienna Limited, but it's really based on which bike rack you're using and where your vehicle's 4-way trailer wiring connector is located instead of based on the vehicle you use it with.

Thule recommends the # TH57SA when using the Thule Tail Light Kit and License Plate Holder # TH24SA with the 4-bike Thule Verse # TH96SA, since the longer rack can require some extra wiring to reach the vehicle's connector.

I actually went out to our warehouse and measured both parts myself. The # TH24SA has a 6' wiring harness, measured from the license plate bracket to the 4-pin connector, while the # TH57SA adds another 18" of length.

To see whether you'll need the extension, I'd recommend measuring the path the wiring will follow from the license plate bracket on your bike rack to the 4-way connector on your Sienna. Be sure to account for the wiring routing around the rack's frame and any moving parts, rather than just measuring in a straight line.

You also don't necessarily have to use Thule's extension. A standard 4-way-to-4-way extension like the # TS88QR is the same 18" length and uses the same style of connector.

Which bike rack are you using on your Sienna? If you can let me know, I can help you narrow down whether that extra 18" will be necessary!