Troubleshooting Magnetic Trailer Light Set Operation

Updated 06/17/2021 | Published 06/15/2021

Question:

I just bought a boat and a trailer came with it. The boat is made of aluminum and there are steel plates at the back for the magnetic trailer lights to stick to. When I brake, the lights act regularly, but when I use the right turn signal, they both flash and when I use the right one, nothing lights up. I resoldered and isolated all the connections and made sure that there are no shorts. Im not sure how grounding works though, and I think that might be the problem. There are no wires for me to clip to the trailer though, so Im just not sure. The lights have a 4 pin connector.

asked by: Dan R

Expert Reply:

The ground circuit for this type of lighting is all tied to the white ground wire.

First step I recommend is using a Test Light # PTW2992 to verify that the issues is with the light string and not the vehicle's 4-way.

Looking at your 4-way plug connector it looks like you have 2 wires switched. The green wire is for your right turn signal/brake light and the white wire is the ground which both are correct on the 4-way. The yellow wire is for the left turn signal/brake light and brown wire is for the running lights which do appear to be switched on your connector.

If you still have the issues with the lighting after correcting the wiring I have linked an article below we have that will explain 4-way wiring better.

You may have an issue as well inside the light assemblies that can cause an internal issue. It may end up best to replace the lights with the Hopkins Magnetic Tow Lights # C6304. These LED lights use a wireless signal to activate the lights which are powered by AA batteries.

expert reply by: Bud M