Troubleshooting Trailer Tail Light Not Working On New Utility Trailer

Updated 10/04/2022 | Published 10/03/2022

Products Featured in This Question

LED Combination Trailer Tail Light - Submersible - 7 Function - 18 Diodes - Square - Passenger Side

(3361)

$26.12

Hook Probe Circuit Tester

(66)

$12.94

LED Combination Trailer Tail Light - Submersible - 8 Function - 21 Diodes - Square - Driver Side

(3361)

$30.22

Question:

I cant figure out why the driver side tail lights on my almost brand new trailer wont work. Everything checks out from the vehicle side, and I cant find any issues with the wiring on the trailer no loose connections, no corrosion, nothing. The only thing I havent been able to check is inside the unit itself, but how do I get the cover off? Theres no screws, no tabs, no nothing. So do I just say the hell with it and buy a new one?

asked by: Travis

Expert Reply:

What you are experiencing is common with ground connection issues. Before you get new tail lights you will first want to find the ground connection. This is generally a screw or bolt that is mounted to the trailer. It is common for trailer builders to use the mounting hardware for the tail lights to make the ground connection. They often will not actually clean the paint off where the wire connector meets the frame and rely solely on the screw to carry the current. This is generally not enough and leads to the issue you are having. You can also test the power going into the light using a Circuit Tester # PTW2993.

Since your tail lights have a sealed housing you will want to replace them with the LED Combination Trailer Tail Light for the Driver's Side # STL3RB and Passenger's Side # STL2RB.

expert reply by: Bud M