When should a driver perform brake testing on a trailer?

Performing brake testing on a trailer before every trip is essential for ensuring the safety and functionality of the braking system. This practice allows the driver to verify that the brakes respond properly, ensuring that the vehicle can stop effectively, especially when carrying a load. Regular brake testing helps identify any potential issues with the braking system early on, thus preventing accidents or failures during operation.

Conducting brake tests consistently before each trip is critical as it accounts for changes that may occur in the braking system due to wear, environmental conditions, or operational factors. By making this a part of the pre-trip routine, drivers ensure that they can operate their vehicle safely and legally while on the road, adhering to safety regulations and best practices for commercial driving.

Other options suggest less frequent testing or only testing under certain conditions, which may not adequately ensure the trailer's braking reliability. Regular pre-trip testing is a proactive measure for safety.