What is the main function of a breakaway switch?

The main function of a breakaway switch is to apply the brakes on a trailer in the event of a trailer release. This safety device is designed to prevent a potentially dangerous situation where a trailer becomes detached from the towing vehicle while in motion. When the breakaway switch is activated, typically by a cable that pulls the switch when the trailer disconnects from the vehicle, it sends a signal to engage the brake system on the trailer. This action reduces the risk of the trailer rolling uncontrolled and helps ensure the safety of both the trailer and other road users.

Other choices focus on aspects unrelated to the primary safety purpose of the breakaway switch. For instance, enhancing speed, securing a trailer during transport, or monitoring weight do not align with the essential function of preventing accidents associated with trailer detachment. Thus, the correct identification of the breakaway switch's role is crucial for understanding trailer safety mechanisms.