Wiring to Connect 5-Flat on Trailer and 4-Round on Boat to 5-Flat on Tow Vehicle
Question:
I have a boat with a 4-pin round connector in the bow to engage built-in boat transom lights when the vehicle brakes. The vehicle end connector is a 5-pin flat. I am looking for a way to split the 5-pin flat from the vehicle to connect to the 5-pin trailer connection AND the 4-pin round connector in the bow. The boat manufacturers part is $$$$$. I have checked the trailer section on your website but do not see a solution ........ any ideas? Thank you.
asked by: Rick M
Expert Reply:
Although we do not carry a wiring harness/adapter that will allow you to split the 5-flat on your tow vehicle to allow you to connect to both the 5-flat on the trailer and the 4-round on the boat, I have a solution for you.
You will need the RoadMaster 4-Wire Connectors, # RM-910030-4, Jacketed 4-Wire (sold by the foot), # DW03240-1, and the Deka Heat Shrink Butt Connectors, # DW05745-5.
I recommend that you splice into the wiring, behind the 5-flat on your trailer, in order to add the 4-round. You will want to start by checking the pin functions on the 4-round on the boat using a circuit tester like part # PTW2993. Depending on which end that you need, you will wire the 4-round trailer or vehicle end using the jacketed 4 wire and connect those wires to the like function on the 5-flat wiring on the trailer with the Deka Heat Shrink Butt Connectors, # DW05745-5. Lastly, I recommend wrapping all of the wiring connections with electrical tape and you should be ready to go.
Products Referenced in This Question
Deka Wire - Jacketed 4-Wire - 16/4 Gauge - per Foot
- Wiring
- Wire
- Jacketed Wire
- 4 Wire
- 16 Gauge
- Deka
more information >
Deka Heat Shrink Butt Connector - 12-10 Gauge - Nylon Insulation - Yellow - Qty 5
- Wiring
- Wire Connectors
- Butt Connectors
- 12-10 Gauge
- Deka
more information >
Product Page this Question was Asked From
RoadMaster 4-Wire Connectors - Trailer and Vehicle Ends
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- Plug Only
- 4 Round
- Roadmaster
more information >
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