Is 3.6V on 2020 Jeep Wrangler Unlimited Trailer Plug Abnormal

Published 09/13/2022

Products Featured in This Question

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

(372)

$99.23

Curt Spectrum Trailer Brake Controller - Dash Mounted Knob - Up to 4 Axles - Proportional

(412)

$259.95

Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires

(3398)

$119.77

Question:

The trailer brake output blue from the Curt Spectrum Trailer Brake Controller is constantly at 3.4V. Is this a problem?

asked by: Masakazu A

Helpful Expert Reply:

If it's just a 4-Way Flat connector like the T-On # 118786 then I would be surprised to see that much power being pulled to the back of your 2020 Jeep Wrangler Unlimited, but if you have a 7-Way like what we find with the Wiring Kit # ETBC7 then 3.6V on the 12V power pin isn't out of the ordinary and you'll be fine.

Attached are photos showing the functions per pin on both a 4-Way and a 7-Way connector for you to reference.

expert reply by: Jon G

7-Way Connector Functions
(click to enlarge)

4-Way Connector Functions
(click to enlarge)

Masakazu A.

9/13/2022

The trailer brake output blue from the Curt Spectrum Trailer Brake Controller is constantly at 3.4V. Is this a problem?

Jon G.

9/13/2022

Thank you for the follow up! Seeing some power on the brake output for a brake controller, like your Curt Spectrum # C51170, is perfectly normal as this is the brake controller's way of checking to see if/when a trailer is connected. If it were a light circuit I'd be a bit concerned but since it's for the brake controller you're good to go.