Troubleshooting Trailer Taillights Not Bright on Aluminum Trailer Frame
Updated 12/09/2025 | Published 11/19/2025
Question:
Hi, on a 2015 Triton TC-128 2 place snowmobile trailer: Marker lights on: Left trailer taillight is brighter than the right, left turn signal does not work. Right turn signal works. Marker lights off, brakes on, hazard lights on: left turn signal works. It was worked on a year ago for some of the left side marker lights and left taillight not working. The problem was fixed. I dont know if the current problem started before or after that work. It was done by a former Triton dealer. All functions on truck work. Voltage in connection after taillight is 14.4 Truck was just turned on. From that connection, ground wire to aluminum trailer frame was 6 ohms. I checked it with another truck and the same issue is there. Any help would be appreciated. Thanks.
asked by: Dennis
Expert Reply:
Hey Dennis, the issue is that the lights are grounding to aluminum which just does not conduct well enough. You would need to run the ground circuits of each light back to the main ground harness of the trailer wiring so that it will be able to complete the circuit well enough to function like it needs to.
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Jameson C.
12/8/2025
Hey Dennis, did running each light’s ground back to the main harness fix the brightness and turn signal issues on your Triton trailer? Knowing how that worked out could help others chasing similar grounding problems.