What is the initial step an engineer should take if the brakes are not engaging?

The initial step an engineer should take if the brakes are not engaging is to inspect for air leaks. Air leaks in the braking system can significantly impact the operation of the air brakes, as they rely on compressed air to function. If there is a leak in the system, it can lead to a loss of pressure, preventing the brakes from applying properly.

By checking for air leaks first, an engineer can identify any potential issues that might be causing the brakes to show insufficient engagement. This step is crucial because, without resolving air leakage, other actions—such as replacing brake pads, adjusting the brake lever, or checking the brake fluid level—may not effectively solve the problem. Each of these steps is important but should be considered after ruling out air leaks, which are often the most common and immediate issue in air brake malfunction.