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.
Continue Researching
- Shop: Trailer Wiring
- Video: An In-Depth Look at the Curt T-Connector Vehicle Wiring Harness for Factory Tow Package-C55245
- Video: Mounting Bracket 4-Pole Flat: The Breakdown
- Shop: Curt T-Connector Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector
- Search Results: i26
- Search Results: 126 tester
- Video: Checking Out the Brophy 4- and 5- Way Flat Circuit Tester
- Video: Hands-On with the Brophy Circuit Tester for 4-Pole Flat Trailer Connector
- Shop: Brophy 4- and 5- Way Flat Circuit Tester
- Shop: Brophy Circuit Tester for 4-Pole Flat Trailer Connector
- Shop: Curt LED 5-Way Flat Circuit Tester - Vehicle End
- Shop: Trailer Hitch
- Shop: etrailer Trailer Hitch Receiver - Custom Fit - Matte Black Finish - Class III - 2"
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Video: Clean Up Your Trailer Wiring
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Search Results: trailer hitch
- Article: Trailer Wiring Diagrams
- Search Results: trailer wiring
- Video: Feature Breakdown: Universal Installation Kit for Trailer Brake Controller
- Q&A: What is the Difference Between a 4-Way and 7-Way Trailer Connector
- Shop: Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Search Results: trailer tires and wheels
- Video: Curt Mounting Bracket for 4-Pole Flat Trailer Connector Review
- Q&A: Lug Nut Torque Chart for Trailer Wheels
- Shop: Suspension Enhancement
- Article: How to Choose the Right Trailer Hitch Class
- Shop: etrailer Trailer Hitch Receiver - Custom Fit - Matte Black Finish - Class III - 2"
- Search Results: trailer hitch ball mount
- Article: How to Measure for Trailer Hitch Drop
on Custom Fit Vehicle Wiring
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.