Gooseneck Trailer Lights Get Brighter on One Side and Marker Lights Come on with Brake Lights
Question:
I have a 7 pin gooseneck trailer. Recently the left side side marker, brake lights etc. have gotten brighter than the right. The side marker lights on the left side come on when the brakes are applied. Any ideas? I have checked all the grounds I could find. It does this with two different trucks, so I am fairly sure it is in the trailer wiring. The trailer is a 28 pj. Any suggestions would be appreciated. - Thank you.
asked by: Bruce B
Expert Reply:
Checking the grounds was a good place to start. I think that it still may be a ground issue. There are several things you can check to determine if it is a ground problem. I would start with the trailer side connector and check for any dirt or corrosion and clean it out. Dirt and corrosion could cause a bad connection or a short which would lead to undesired results.
Next, I would check the ground coming out of the back of the trailer connector. It should be connected to a clean and corrosion-free bare metal surface on the trailer frame. A bad ground here could cause the lights to not work, work intermittently, or other unwanted performance. You can also check to make sure the wiring is not broken or frayed.
Next, I would move on to checking the grounds at the lights themselves. Many trailer lights ground through the mounting studs unless there is a ground wire attached. Again, the grounds will need to be attached to a clean and corrosion free surface. While checking the grounds at each light, you can also checking for any loose or broken wires that may be causing the problem.
I have included links to some videos showing how to check for a proper ground that may also help.
Product Page this Question was Asked From
Hopkins 7-Way RV Style Connector with Molded Cable - Trailer End - 8' Long - RV Standard
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 6 - 10 Feet Long
- Plug and Lead
- 7 Round - Blade
- Hopkins
more information >
Featured Help Information
Instructions
Miscellaneous Media
Continue Researching
- Q&A: Trailer Lights are Dim Just on One Side of Trailer
- Q&A: How to Tell If MORryde Rubber Equalizers Will Fit Trailer
- Article: Trailer Wiring Diagrams
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Article: How to Install E-Track in 3 Easy Steps
- Q&A: Brake Controller Installation on 2016 Mercedes-Benz Sprinter
- Q&A: Replacement Kwikee Electric Steps for a 2005 Jayco Greyhawk 31SS
- Q&A: Is Bow in 3,500 lb Trailer Axle Enough Camber for Loaded and Unloaded Trailers
- Q&A: Replacement Connector for a Pollak PA66-MD40
- Q&A: Correct Replacement for AL-KO 7230 Hub/Drum and Brakes
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Article: 7 Common Questions Everyone Has About Trailer Tires
- Article: Calculating Portable Generator Power Needs
- Article: Parts Needed to Add Electric Drum Brakes to a Trailer