Only Blinkers Are Working on Boat Trailer
Question:
Blinkers are working on both sides but the brake lights, tail lights and the clearance lights are not working. I am guessing it’s a ground issue but the only grounds are at the tail lights and the blinkers are working.
asked by: Jz
Expert Reply:
There are a number of potential issues to check out if just your blinkers are working on your trailer. You can start by checking the ground, as that does cause funky issues, so make sure they're attached to bare metal surfaces and free of any paint, dirt or corrosion.
After that, take a look at your owner's manual to locate any trailer fuses or relays and ensure they are all there and in working order. If they are, in order to determine the specific problem you will need to purchase a circuit tester if you do not have one - the very handy Cordless Circuit Tester # PTW2979 would be my strong recommendation due to how easy it is to use - and test the connector on your vehicle after disconnecting it from your trailer. Check the wiring going into your harness from your tail lights to see if those wires are carrying the correct signals, if not then the issue is with the vehicle wiring.
If the signals going to your harness are okay, you'll need to test the signals coming out of the harness, and if they are correct then your issue is likely going to be with the trailer side wiring. You will also want to check both your vehicle and trailer connectors for corrosion, which can be green or white in color. A build-up of corrosion can interfere with the signals getting through the connectors so if it is present you are going to need to replace the 4-way with # 18004.
I have added links to a pair of help articles on trailer wiring, including a troubleshooting guide which I highly recommend taking a look at. Additionally, I also highly recommend using Dielectric Grease for Electrical Connectors # 11755 to help prevent any type of corrosion in your connector; using it will increase your 4-way's durability and extend its lifespan
Products Referenced in This Question
Dielectric Grease for Electrical Connectors, 2 oz.
- Accessories and Parts
- Trailer Wiring
- Wiring
- Dielectric Grease
- LubriMatic
more information >
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 0 - 5 Feet Long
- Plug and Lead
- 4 Flat
- Draw-Tite
more information >
Product Page this Question was Asked From
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