Troubleshooting Trailer Wiring that Needs to be Cleaned Every Time it is Used
Updated 09/22/2025 | Published 09/18/2025
Question:
I have two trailers boat and kayak. Invariably, when I connect the electrical to the car for both trailers the right turn signal does not work. After I clean the connections with alcohol, it works. Both are stored inside the car plug has a cap. I understand connections can oxidize, but this is every time, even twice within the same day. Does this suggest a problem with the connection on the car? Very weary of the constant need to scour connection. Any thoughts are welcome. Thanks for any insights you can provide.
asked by: Michael R
Expert Reply:
Hey Michael, that is a really odd problem to have but I would think the issue is actually that the right stop/turn circuit on the vehicle's trailer wiring connector is bent or damaged and just can't make great contact consistently. I would inspect that pin and let me know what it looks like. Most likely every time you clean it you are just putting it back in all the way and it's finding a way to slip out a little as you drive.
Product Page this Question was Asked From
Hopkins Plug-In Simple Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Powered Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Hidden
- Hopkins
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Michael R.
9/18/2025
Interesting. Will do. Hard to see the right turn pin inside the plastic housing. Is it hard (for a layman) to replace that four-pin connection on a Toyota Highlander? Thank you.