Where does the power for the trailer brakes come from when the brake-away switch is activated?

When the brake-away switch is activated, the power for the trailer brakes is provided by the coach battery. The brake-away switch is a safety feature that activates the trailer's brakes in the event that the trailer becomes disconnected from the tow vehicle. This mechanism relies on its own power source to ensure that the brakes engage promptly, preventing potential accidents.

The coach battery, which is typically part of the trailer's electrical system, is designed to supply power to various systems when the trailer is disconnected from the vehicle. This is crucial because the brake-away switch's main purpose is to engage the trailer brakes automatically to help keep the trailer under control. Choosing the coach battery as the source for this power ensures that the brakes can function independently and effectively during a disconnection scenario, enhancing safety on the road.

Other options, such as a generator battery, vehicle alternator, or auxiliary battery, do not serve the same purpose or may not be available in the scenario where the brake-away switch is in use. The correct choice emphasizes reliability and safety in the design of trailer braking systems.