Troubleshooting Trailer Connector On 2015 Nissan Frontier When Tail Lights Do Not Work

Updated 07/11/2017 | Published 07/08/2017

Products Featured in This Question

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

(490)

$65.02

Hook Probe Circuit Tester

(70)

$12.41

Question:

i have a question regarding the Curt wiring harness, if i already have brake and turn signals at the 4 pin trailer, why do i need this complete harness, only thing missing is taillights

asked by: Kent B

Expert Reply:

If you have a 4-way trailer wiring harness on your 2015 Frontier, the taillights should be working as well as the turn and brake lights.

I recommend using a circuit tester like part # PTW2993. Have someone run through the functions while you check the pins on the harness. If any functions are not working, you will need to make sure all the fuses are good. If they are all okay, then start checking the wiring from the trailer connector forward.

There may be a loose or damaged wire or a ground that is not secured to a clean metal surface. You may have a harness and possibly the relay is missing. The relays included with the Curt T-Connector harness # C56225 are needed to activate the tow package on your Frontier.

expert reply by: Jeffrey L