Breakaway trailer brakes are a critical safety feature designed to automatically apply the trailer’s brakes if it becomes detached from the tow vehicle. This system uses a simple yet effective mechanism to prevent a runaway trailer, potentially averting accidents and protecting lives.
The Core Functionality of Breakaway Brakes
At its heart, the breakaway system relies on a small battery, a breakaway switch, and the trailer’s existing electric brakes. When the trailer is properly connected to the tow vehicle, a lanyard or cable connects the breakaway switch to the vehicle. Should the trailer disconnect, this lanyard pulls a pin from the breakaway switch. This action completes an electrical circuit, drawing power from the dedicated breakaway battery to activate the electric brake actuators on the trailer axles. These actuators then press the brake shoes against the drums or rotors, engaging the brakes and bringing the trailer to a controlled stop.
The system is specifically designed to function independently of the tow vehicle’s electrical system, ensuring braking even if the trailer wiring is severed during the disconnection. The breakaway battery is essential for this independence, providing the necessary power to operate the brakes for a limited time, usually around 15-20 minutes, depending on the battery size and brake usage.
Understanding the Key Components
Breakaway Switch
The breakaway switch is the central control point of the system. It’s typically a small, spring-loaded switch with a pin that, when removed, completes the electrical circuit to activate the brakes. The lanyard connects to this pin, ensuring that separation activates the braking mechanism. Different types of breakaway switches exist, but they all share the same fundamental principle of operation.
Breakaway Battery
A dedicated 12-volt breakaway battery is mandatory for most trailers equipped with electric brakes. This battery is housed in a protective case, often mounted on the trailer’s A-frame. It must be regularly charged to ensure its readiness in an emergency. Many systems include a charging circuit that draws power from the tow vehicle while connected, although this system needs to be checked to ensure proper functionality. Periodic battery testing is crucial.
Electric Brake Actuators
These devices are responsible for converting the electrical signal from the breakaway switch into mechanical force to apply the brakes. They consist of an electromagnet that, when energized, pulls a lever to activate the brake shoes. The strength of the electromagnet dictates the braking force applied. Modern electric brake actuators are generally reliable, but regular inspection and maintenance are essential.
Electric Brakes
The electric brakes themselves are the standard braking system on the trailer, utilizing either brake drums or rotors. Their operation is similar to traditional hydraulic brakes, except they are activated by an electrical signal rather than hydraulic pressure.
Maintenance and Inspection
Regular inspection and maintenance are crucial to ensure the breakaway system functions correctly when needed. This includes checking the battery’s charge level, inspecting the breakaway switch for damage, and ensuring the lanyard is properly connected and in good condition. Neglecting these simple checks can render the system ineffective.
Battery Maintenance
The breakaway battery is the most critical component requiring regular maintenance. It should be fully charged and free from corrosion. A simple voltmeter can be used to check the battery’s voltage. If the voltage is low, the battery should be charged or replaced. Regular testing, at least monthly, is recommended.
Switch and Lanyard Inspection
The breakaway switch and lanyard should be inspected for signs of damage, such as cracks, fraying, or corrosion. The lanyard should be securely attached to both the switch and the tow vehicle. The pin should be easy to remove and insert.
Brake Function Testing
Periodically test the entire system by manually pulling the breakaway switch pin. This should immediately activate the trailer brakes. If the brakes do not engage, troubleshoot the system to identify the cause of the malfunction.
Frequently Asked Questions (FAQs)
1. Are breakaway brakes required by law?
Yes, in most jurisdictions, breakaway brakes are legally required for trailers exceeding a certain weight threshold, typically around 3,000 pounds (1,360 kg) gross vehicle weight rating (GVWR). Specific regulations vary by state or province, so it’s crucial to check local laws.
2. How long will a breakaway battery last?
A fully charged breakaway battery should typically provide enough power to operate the trailer brakes for 15-20 minutes. The exact duration depends on the battery’s amp-hour rating, the number of axles on the trailer, and the terrain.
3. Can I use any battery for the breakaway system?
No, it is crucial to use a dedicated 12-volt battery specifically designed for breakaway systems. Using a different type of battery could damage the system or render it ineffective. Marine batteries are a common choice, as they are designed to handle deep discharges.
4. How do I charge the breakaway battery?
Many trailers have a charging circuit that draws power from the tow vehicle’s electrical system while connected. However, this circuit should be checked regularly to ensure it’s functioning correctly. Alternatively, a separate battery charger can be used to charge the breakaway battery.
5. What happens if the breakaway battery is dead?
If the breakaway battery is dead, the breakaway brakes will not function in an emergency. This highlights the importance of regular battery maintenance and testing. Consider carrying a spare, fully charged battery as a backup.
6. How often should I test the breakaway system?
The breakaway system should be tested before each trip. This includes checking the battery’s charge level, inspecting the switch and lanyard, and manually activating the brakes to ensure they are functioning correctly.
7. Can I replace the breakaway switch myself?
Yes, replacing a breakaway switch is a relatively straightforward task that can be performed by most trailer owners. However, it’s important to follow the manufacturer’s instructions carefully and ensure the wiring is properly connected. If you’re unsure, consult a qualified trailer technician.
8. What should I do if the breakaway brakes activate while driving?
If the breakaway brakes activate while driving, it indicates that the trailer has become detached from the tow vehicle. Immediately pull over to a safe location and assess the situation. Determine the cause of the detachment and make necessary repairs before continuing.
9. Are there different types of breakaway switches?
Yes, while the fundamental principle remains the same, there are different types of breakaway switches. Some have a larger pin, while others have a different mounting style. Choose a switch that is compatible with your trailer and easy to operate.
10. Can I use the breakaway system as a parking brake?
No, the breakaway system is not designed to be used as a parking brake. Using it repeatedly for this purpose can drain the battery and damage the brake actuators. Use wheel chocks instead for parking.
11. What is the lifespan of a breakaway battery?
The lifespan of a breakaway battery typically ranges from 3 to 5 years, depending on the quality of the battery and how well it is maintained. Regular testing and proper charging can extend the battery’s lifespan.
12. What if my trailer uses hydraulic brakes?
Trailers with hydraulic brakes typically use a surge brake actuator, which utilizes the inertia of the trailer pushing against the tow vehicle to apply the brakes. In these systems, a breakaway cable is connected to the tow vehicle. If the trailer detaches, the cable pulls a lever on the surge actuator, locking the brakes. The breakaway mechanism prevents the actuator from returning, maintaining braking force.
By understanding how breakaway trailer brakes work and performing regular maintenance, you can ensure the safety and reliability of your trailer, protecting yourself and others on the road.