How Breakaway Kits Work


In the unlikely but dangerous case of a separated trailer, a breakaway kit is a simple but necessary solution that applies electric brakes to towed vehicles the moment they become unhitched. See more truck pictures.

In train robbery films, there's almost always a scene where the group of thieves unhitch the car with the loot in it and divert it to a safe, secure spot. In this scenario, the crime ring has control of where the car will end up -- at least, until the good guys get there to reclaim it.

When you're driving a tow vehicle and pulling hundreds or even thousands of pounds behind you, robbers might not be your worst fear. A loose trailer, however, may be something to worry about, especially if there's no one to guide or stop it.

­Of the many potential hazards that come with a towing trip, a breakaway may be the scariest and most precarious. While drivers can correct certain conditions like trailer sway, for example, a breakaway will leave you with absolutely no control over the vehicle you formerly were towing. Once a trailer or boat separates from the tow vehicle, unless it's equipped with a functional breakaway kit, the trailer will continue moving forward until it either loses momentum and slows down or hits something else. Breakaway kits aren't just something to consider as an option -- many states require them because of the security they add to towed vehicles.

What types of breakaway kits are available? What should you look for in one? And can you install the kit yourself, or should you have a professional take care of it?

Choosing Breakaway Kits

Choosing the right breakaway kit is fairly straightforward, but there are a few things to keep in mind. Do you want a rechargeable battery? How do you want the kit mounted?
Choosing the right breakaway kit is fairly straightforward, but there are a few things to keep in mind. Do you want a rechargeable battery? How do you want the kit mounted?

Fortunately for consumers, most breakaway kits are pretty similar across the board. They include a plastic bin for a sealed battery, the breakaway switch and proper wiring. They typically weigh between 3 and 8 pounds (1.4 to 3.6 kilograms) and measure about 5 or 6 inches (12.7 to 15.2 centimeters) in height, width and depth, about the size of a thick textbook. Depending on the type of trailer, drivers can mount breakaway kits almost anywhere on their trailer, on the frame or even inside.

Based on the type of kit, prices can vary -- breakaway kits usually cost between $10 and $40, and some can cost as much as $70. Why such a broad price range? First, not all breakaway kits work with every kind of towing setup. One breakaway kit might be designed for single- and tandem-axle trailers, while another might work with single-, tandem- and tri-axle trailers. As a rule of thumb, the more universal a breakaway kit is, the more expensive it will be. Also, if a kit comes with a rechargeable battery instead of a non-rechargeable battery, the price will most likely be higher; however, these are usually a better deal, since you won't have to keep replacing expensive batteries or buy a separate charger.

Find out how to install a breakaway kit to your trailer frame on the next page.

Installing Breakaway Kits

Mounting a breakaway kit is a simple task with the right tools, but if you're not used to working with electrical wiring, you might want to opt for professional installation.
Mounting a breakaway kit is a simple task with the right tools, but if you're not used to working with electrical wiring, you might want to opt for professional installation.

After choosing the right type of breakaway kit, the next step is to install the kit onto your vehicle. There are basically two steps to this: mounting the breakaway kit and switch and connecting the electrical system.

Mounting a breakaway kit is the simplest step, and if you have the right tools you should be able to do it on your own. Most breakaway kits come with either a mounting bracket or they have mounting holes built into the plastic battery box itself, so all you have to do is bolt the kit onto the trailer. Where you choose to mount the battery is up to you -- it can go almost anywhere on the trailer -- even on the inside. Most people choose to place the kit on the trailer frame for easy access.

Mounting the breakaway switch is just as easy. Again, you can mount it nearly anywhere on the trailer, but it's best to keep it away from any space that might be damaged by dragging or debris. Be sure that the switch wiring will reach the trailer hitch, as the disconnection of the trailer hitch is what triggers the breakaway switch.

The next step, properly wiring the breakaway system, may be best handled by a professional. The process involves cutting and splicing several wires together, so unless you're experienced with electrical wiring you might want to leave this step to someone trained in breakaway kit installation.

The wires from the battery connect to the breakaway switch, providing the necessary power. Then the wires from the breakaway switch are spliced to the trailer's brake wires. The breakaway switch, also known as a plunger, is connected to the hitch -- when the trailer separates from the tow vehicle, the switch immediately sends a signal to the trailer's brakes to slow down and safely stop the vehicle.

Don't stop now. For lots more information on braking systems and towing, cruise on to the next page.

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Sources

  • etrailer.com. "Breakaway kits." (Sept. 30, 2008) http://www.etrailer.com/y-266.aspx
  • etrailer.com. "Installation of a breakaway kit with tester and built-in charger." (Sept. 30, 2008) http://www.etrailer.com/tv-demo-breakaway-kit-faq.aspx
  • TJ Trailers. "Breakaway kits." (Sept. 30, 2008) http://www.tjtrailers.com/store/breakaway-kits.html