Wiring a Tow Vehicle to Tow a Dinghy

To tow a dinghy, the tow vehicle must be able to provide basic lighting functions for the dinghy. If there is not already a functioning trailer connector on the rear of the vehicle, one must be added.

• How you wire your tow vehicle depends on the type of lighting system you have on your tow vehicle.
  • Combined system
    • If you have a combined system, your vehicle will carry brake and turn signals on the same wire
    • See "Wiring a Combined Tow Vehicle" below for instructions on installing a basic 4-way trailer connector
  • Separate system
    • Separate systems carry the brake and turn signals on two separate wires, often with the turn signal behind an amber lens
    • See "Wiring a Separate Tow Vehicle" below for instructions on installing a basic 4-way trailer connector

Wiring a Tow Vehicle with Combined Tailight Wiring System

To supply the appropriate circuits for powering the dinghy's tail lights, you need to install a 4-way connector on the tow vehicle that can provide the running light, right turn and brake, and left turn and brake signals

1. You can use a universal wiring kit like 4-Pole Hardwire Kit Including Circuit Tester, part #18252, to provide a 4-way connecter on the rear of the tow vehicle
2. Procedure
   1. Ground the white wire from the wiring harness to a clean, metal surface on the vehicle frame
   2. Using a circuit tester, locate the tow vehicle's factory wires that carry the running light, right turn and brake, and left turn and brake signals
      1. Connect the brown wire to the factory running light circuit
      2. Connect the yellow wire to the factory left turn and brake circuit
      3. Connect the green wire to the factory right turn and brake circuit
   3. Once the wiring is complete, test each pole on the 4-way connector to see if it shows current when the appropriate function is activated
   4. Mount the 4-way on the rear of the tow vehicle in a safe, easily accessible mounting location






Wiring a Tow Vehicle with a Separate Tail Light Wiring System






Install a converter on the tow vehicle to convert its 3-wire system to a 2-wire system and to provide a 4-way trailer connector

• Installation of a converter is necessary for the dinghy's tail lights to function properly while being towed
  • Converting the lights from a separate system to a combined system is recommended because it gives the tow vehicle a connector that can provide the basic light functions for towing a trailer, as well as a vehicle
• A powered, universal kit that can be used to wire most tow vehicles is the Heavy Duty Modulite Circuit Protected Vehicle Wiring Harness with Install kit, part #119190KIT. Ensure that you follow manufacturer's instructions when installing this kit.
  • There are some cases when a non-powered converter can be used. However, if you do not have a way to determine which converter you need, the safest option for your tow vehicle will be a powered converter.
• Procedure
  1. Ground the white wire from the converter to a clean, metal surface on the tow vehicle chassis
  2. Using a circuit tester, find the factory wires that carry the brake lights, running lights and right turn and left turn signals on the tow vehicle
     • Connect the red wire from the converter to the factory wire that goes hot when the brakes are pressed
     • Connect the brown wire from the converter to the factory wire that carries the running light signal
     • Run the green wire from the converter to the right side of the vehicle, then connect the green wire to the factory wire that carries the right turn signal
     • Connect the yellow wire from the converter to the factory wire that carries the left turn signal
  3. Once the wiring is complete, test each pole on the 4-way connector to make sure that they show current when the appropriate function is activated
  4. Mount the 4-way on the rear of the tow vehicle in a safe, easily accessible location



Note: Inside the converter box, the brake light signal carried on the red wire is combined with the turn signals carried on the green and yellow wires




Updated by: Raymond P.

Last updated: 6/29/18







Frederick S.
5/21/2021
do I install the 2 to3 box behind the left ta
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Jon G.
5/24/2021
Not sure what wiring you have but typically if there is a converter box it will be closer to either of the tail lights. I would install it wherever it will naturally fit while making sure you have enough wire to reach to the other side of your vehicle for the second tail light.
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Scott B.
4/18/2021
I am getting ready to tow a 2000 blazer from Alabama to California. Tow dolly. I wired a 4 pole to the factory trailer wiring but I can't seem to make the lights work. Any suggestions?
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Jon G.
4/21/2021
You'll need to use a diode kit and wiring like part # RM-152 or a separate light kit like the magnetic lights # 73864 for your application. The factory trailer wiring on your Blazer is meant to send a signal, not receive a signal - that's why you're having issues.
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Scott B.
4/21/2021
@JonG makes sense. I purchased the magnetic lights. Cut the 4 pole off and taped those back up behind the bumper. Thank you for the reply. Still boggles the mind why something that sends a signal can't receive one but meh. Live and learn.
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Philip L.
3/28/2021
I have a 2013 Chrysler S200 that I tow with a dolly. I would like to use the vehicle tail light for better visibility. I'm having a hard time figuring out which kit works properly. Thanks Phil
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Kef G.
3/30/2021
This isn't something I recommend. The tow dollies for your vehicle need to connect to the RV's wiring harness to power not only their own lights but the brakes as well. If you take that up with a wiring kit for your S200's lights, then the lights and the brakes will no longer work.
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Jeff
11/30/2020
On my utility trailer approximately 5×7. All lights are working except the brake lights on trailer. Blinkers and brake light are on same wire. Blinkers work but brake lights don't. How do I fix this problem?
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Jon G.
12/1/2020
Attached is a helpful article on troubleshooting 4-Way and 5-Way trailer connectors. In the first problem it mentions the issue that you are having. Basically the solution is to check all of your wiring for damage, check that your connections are good, and that your grounds are securely connected to a clean, bare-metal surface.
Helpful Links
faq-4-5-way-troubleshooting.aspx
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Dwolf
1/29/2020
I need to add a 12 volt DC positive hot wire to my dinghys brake buddy. I have a Newmar Dutch Star diesel pusher. Do I attach the wire directly to my RV batteries where it is constantly on, to the accessory side of the ignition, or to some point on the engine where the last two choices provide electric while ignition is on? Why always on vs only when ignition is on?
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Jacob H.
2/4/2020
Your break buddy system needs to be connected to a 12v outlet # RM-9332 that will need to be wired to the towed vehicle in case of a breakaway. I always recommend running a charge line # RM-156-25 from the RV back to the towed vehicle so that it keeps your batteries charged while traveling down the road.
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