Trailer Lights Not Working After Installing the Hopkins Trailer Wiring on a 2003 Nissan Frontier

Updated 01/26/2012 | Published 01/24/2012

Products Featured in This Question

Hopkins Plug-In Simple Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(76)

$59.87

Hook Probe Circuit Tester

(60)

$12.41

Question:

we put a wiring kit 33515 on our nissan frontier and the lights on the trailer wont work but we hook up the trailer on a S-10 and they work why wont they work on the nissan?

asked by: Bill

Expert Reply:

It sounds like the converter on your Hopkins wiring harness, # 33515, is not working correctly. The first step I would take is to use a circuit tester, like part # PTW2993, to check the trailer plug on the wiring harness for proper function without a trailer connected. If there is power there when the brakes, turn signals and taillights are activated, then you know that the ground for the wiring is not connected properly, and you will need to check the vehicle connector and trailer wiring for sufficient ground connections.

If you do not have power at the trailer connector, check the wires going into the converter box for proper function. You should get power on the red wire when the brake pedal is pressed, on the yellow wire when the left turn signal is activated, on the green wire when the right turn signal is activated, and power on the brown wire when the taillights are turned on.

If you have power to the converter box and not coming out to the trailer connector the wiring harness will need to be replaced.

If you do not have power to the converter box, check the connection to the vehicle wiring harness and make sure the pins in the connectors are not bent, that the vehicle side connector has power for each of the trailer wiring functions, and that the connectors are snapped together properly.

If the vehicle side connector does not have power for the trailer lighting functions you will need to check the vehicle tow package fuses and relays for proper function.

expert reply by: Robert G