New Side Marker trailer Lights are Very Dim

Question:

I just replaced the marker lights on my boat trailer. I wired the vehicle driver side light into the brown wire using a butt connector. On the vehicle passenger side I did the same thing and somehow it grounded both of them out when both ends of the brown wire and the single, black wire from the optronics marker light were attached together. I was able to remove one end of the brown wire and both marker lights came back on but were very dim. Any ideas? The truck is a 2011 Ford F150, the boat is a 2007 Tahoe Q6 with the 5-pole flat connector.

asked by: Gregory T

Expert Reply:

It sounds like a bad ground connection. Ground problems normally show up when there is more draw on a system such as when you have the running lights on and then use another function like a turn signal or brake light. But can also appear when changing out lights.

Make sure that the vehicle side and trailer side connectors are clean and free of corrosion inside and out. The main connector grounds should be attached to clean and corrosion free bare metal surfaces.

The light grounds should also be attached to clean and corrosion free bare metal surfaces. If there is anything between a light ground and the metal trailer frame or if the trailer has an aluminum frame, tilt bed, or folding tongue, any of these things can interrupt the ground. Running jumper wires from the light grounds to the main trailer connector ground can help.

expert reply by: Michael H