Availability of 4-Way Flat to 6-Way Round Adapter
Updated 11/13/2025 | Published 10/19/2025
Question:
I have a 2018 Nissan Pro - Max with factory flat 4. I have a small 1996 camp trailer with Round six plug. The trailer has separate tail light and turn signal lights. It also has a stop logic for 3rd brake light. 2 questions - do you make conversion plug that will work flat 4 to round 6? Second - I wired a round 6 on the truck side by going directly from each tail light. The only thing not working are the blinkers which do blink but only once, if I move the lever it will flash. Do I need to add another flasher relay ? I cleaned and installed new hardware for each ground truck/trailer and verified all wires are good. Thank you for assistance
asked by: Jesse G
Expert Reply:
Hey Jesse, we do have a 4-flat to 6-round adapter with the part # 37175. This would allow the 6-way of your trailer to plug into a 4-way on a vehicle.
Your other problem about the trailer wiring that is ran to your vehicle taillights is probably due to how the vehicle taillight wiring is configured. Does the vehicle have turn signals that are amber and separate from the stop lights? if so. this is true. What is the vehicle though? I can see if there's an easier 4-way solution.
Product Page this Question was Asked From
Adapter 4 Pole to 6 Pole and 4 Pole Trailer Wiring Adapter
- Custom Fit Vehicle Wiring
- Wiring Adapters
- Universal Fit
- 4 Flat to 6 Round
- Plug and Lead
- Hopkins
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Jameson C.
11/13/2025
Hey Jesse, what ended up working with the 4-flat to 6-round adapter on your Nissan and trailer setup? Did it take care of the blinker issue you mentioned? Your update could make it easier for others with similar wiring differences.