When should you conduct a brake system test after starting your vehicle?

Answer: C — Immediately after starting the vehicle

Conducting a brake system test immediately after starting the vehicle is essential for ensuring safety before you begin to operate the vehicle. This practice allows the driver to assess the functions of the brake system while the vehicle is still in a stationary position. It helps identify any issues that may exist with the air pressure in the brake system or with the brakes themselves, such as leaks or malfunctions. Performing the test right after starting the engine allows for immediate monitoring of the pressure build-up, essential for safe operation of air brake systems. It's a proactive step to ensure that once you hit the road, the vehicle's braking performance is reliable and effective. Engaging in the brake system test at other times, such as after driving for a while or waiting for the vehicle to warm up, may not provide accurate feedback about the initial condition of the brakes before the vehicle begins moving. Therefore, conducting this test immediately after starting is the safest and most effective practice.