Determining Wire Function On Boat Trailer With No Trailer Connector
Question:
I bought a boat on wholesale, and only loose wires are hanging out of the trailer. The trailer per the registration is a 2007 Karavan, Model US-4100-SSB-78-ST-BLW. Do you have the correct parts so I can attach these loose wires to some type of plug? Id prefer to attach the wires to the most compliant plug, and the convert the plug with a converter down to a 4 flat which is what I will be using the majority of the time to pull the trailer. Can you help? Im trying to attach a picture of what I see coming out of the trailer, I have multiple pictures that I tried to attach but it looks like only one attached. Im not sure which one ended up getting attached. It looks like a set of yellow wires and a set of green wires, and two sets of brown and white wires with plugs. The Yellow and Green are loose hanging wires.
asked by: Brian K
Expert Reply:
It sounds like someone ran the wires as what we call a wishbone. The only way to tell how the wiring is connected to the lights is to use a 12V battery and a circuit tester like part # PTW2993.
Attach the white ground wire to the battery negative terminal and then one by one connect the other wires to the positive terminal. You can have someone watch the trailer lights while you do the testing to determine what function each wire carries. Depending on how many lights you have on the trailer you may find the wires are for marker or clearance lights on the side of the trailer that can be wired into the running light circuit. You can use butt connectors like part # DW05744-10 for the wiring.
Once you determine what each of the wires are for you can use a 4-way trailer wiring harness like part # W787264.
I have attached a helpful article about trailer wiring you can check out.
Products Referenced in This Question
Deka Heat Shrink Butt Connector - 16-14 Gauge - Nylon Insulation - Blue - Qty 10
- Wiring
- Wire Connectors
- Butt Connectors
- 16-14 Gauge
- Deka
more information >
Wesbar 4-Pole Flat Connector w/ Jacketed Cable - Trailer End - 4' Long
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 0 - 5 Feet Long
- Plug and Lead
- 4 Flat
- Wesbar
more information >
Product Page this Question was Asked From
7-Way Molded Trailer Wire Connector, 6' Long
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 6 - 10 Feet Long
- Plug and Lead
- 7 Round - Blade
- Hopkins
more information >
Continue Researching
- Article: Trailer Wiring Diagrams
- Video: The Low-Down on the 7-Way Molded Trailer Wire Connector, 4' Long
- Shop: 7-Way Molded Trailer Wire Connector, 4' Long
- Shop: Optronics LED Clearance or Side Marker Light - Submersible - 3 Diodes - Rectangle - Amber Lens
- Shop: Trailer Wiring
- Video: Hands-On with the 7-Way Molded Trailer Wire Connector, 4' Long
- Video: Comprehensive Review: Optronics LED Clearance or Side Marker Light
- Q&A: Installing 7-Way Wiring Connector to Trailer For Reverse Light Function
- Q&A: Difference Between 7-Way Round and 7-Way Blade Connectors
- Search Results: trailer wiring cable
- Search Results: trailer wiring clips
- Search Results: heat shrink butt connectors
- Search Results: trailer wiring
- Search Results: zip tie
- Shop: CE Smith Trailer Wiring Clips - Frame Mount - Zinc Plated Steel - Qty 10
- Shop: V-Shaped Identification Light Bar for Boat Trailers - Submersible - Red LEDs - Red Lens
- Video: Comprehensive Review: V-Shaped Identification Light Bar for Boat Trailers
- Article: Trailer Lighting Requirements
- Video: Ultimate Overview of the Hopkins 7-Way RV Style Connector with Molded Cable
- Shop: Hopkins 7-Way RV Style Connector with Molded Cable - Trailer End - 8' Long - RV Standard
- Shop: Mighty Cord 7-Way RV-Style Trailer Connector w/ Molded Cable - Trailer End - 6' Long
- Search Results: side marker lights
- Video: All You Need to Know About the Optronics LED Clearance or Side Marker Light
- Video: A Closer Look at the Optronics LED Clearance or Side Marker Light
- Shop: etrailer Bolt-On Swivel Mounting Plate for 3,500-lb Trailer Jacks with a 5/8" Swivel Pin
- Shop: Trailer Hitch
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Q&A: What is the Difference Between a 4-Way and 7-Way Trailer Connector
- Search Results: trailer hitch
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)