Directional Lights Blinking When Brakes Are Pressed On Harness C57ER On A 2021 Toyota Venza

Updated 09/29/2025 | Published 05/08/2025

Products Featured in This Question

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

(104)

$106.67

Question:

I bought a curt trailer harness C57ER from you and have it installed on my 2021 venza. If like to know if theres any adjustment i can make to stop the directional lights from blinking when I press the brake pedal. Look forward to your response. PR

asked by: Pablo R

Expert Reply:

Hey Pablo,

It sounds like there could be a possible issue with the ground or a short somewhere in that harness. I recommend first checking your ground wire that it is properly grounded. You'll want to make sure it is grounded on to clean bare metal, preferably on the frame for it to be properly grounded.

If that doesn't change the issue I recommend testing the circuits of the harness before and after the converter box. You'll want to make sure they are correct going into the converter box, and coming out. If it is wrong coming out its going to be a bad converter box. There is not an adjustment to really be made, you will just need to check the connections and the ground to make sure they are all set and test the circuits to see if you can identify the issue.

How long have you had the harness? If the issue is still there after doing those please let me know and I can continue to dig into some troubleshooting options for you.

expert reply by: Nick S

Nick S.

9/29/2025

Hey Pablo, did you have a chance to check the ground wire and test the circuits as suggested? If the issue is still there, I'm here to help with more troubleshooting options.