When should the lights and buzzers activate in the air brake check?

The lights and buzzers in the air brake check activate after continuously pumping the brakes because this action simulates the depletion of air pressure in the system. During this check, you want to monitor how the air pressure drops in order to evaluate the effectiveness of the brake system. Once the air pressure falls to a preset level, usually around 60 PSI, the warning lights and buzzers will trigger, alerting the driver to the situation.

This warning mechanism is crucial as it helps maintain safety on the road. If the driver fails to notice the warning signals, they might operate the vehicle at dangerously low air pressure, which could lead to brake failure. The activation of the lights and buzzers serves as an essential alert system to ensure that drivers are aware of their brake system's functioning and can take necessary action before it becomes critical.

Other choices do not accurately reflect when the indicators should activate. For instance, waiting until the vehicle reaches 0 PSI would be too late for safety measures, while the idea of activating them after 10 pumps does not account for variable air loss in different braking systems. Similarly, the statement regarding the engine being off doesn't align with the engine's operation when the brakes are engaged and depleted.