What must be done after reducing the air pressure during the alarm check?

After reducing the air pressure during the alarm check, turning the ignition key off is crucial for several reasons related to vehicle safety and proper operation. When the ignition is off, it ensures that the bus systems are not active, allowing you to conduct the alarm check without interference. This procedure allows for a clear observation of how the air pressure responds and ensures that the vehicle’s air pressure systems are functioning correctly without the risk of unintentional activation of other systems.

Furthermore, turning the ignition off may help prevent electrical issues or inadvertent vehicle movement during the checks, enhancing safety for both the driver and passengers. This practice aligns with standard operating procedures for school bus safety, ensuring that all necessary precautions are observed.