Trailer Taillights Have Power at Light Connector And Light Bulb Will Not Light

Question:

I have one side of the trailer with the tail light not lighting when signaled. Separate running lights are working. The wires and light connector have been tested for power along with ground i.e. using a probe it will flash, or light when brake, turn, hazards are applied, however, the bulb itself will not light. I have replaced the entire tail light with a new assembly and have the same problem. Power to the light bulb connector but bulb will not light. I have tried 4 new bulbs so it is not the bulb. I am stumped - any help appreciated.

asked by: Wayne

Expert Reply:

If you are getting power to the light but nothing with the bulb it sounds like it has to be a ground issue.

I thought it might have been a issue with the bulb connector but since you changed out the entire assembly it seems hard to believe that it would be the issue with both assemblies.

I recommend checking the ground connection for the light for any built up corrosion.

I have linked an article below that covers troubleshooting trailer lighting issues.

expert reply by: Bud M