If the parking brake is re-applied after manual release, what does this indicate?

When the parking brake is re-applied after a manual release, it indicates that the manual release was successful. This means that the brake system was properly disengaged, allowing the train to move freely. The ability to reapply the brake after having voluntarily released it demonstrates that the brake system is operating as intended.

In this context, if the manual release didn't work as expected, the parking brake would not be able to be reapplied. Therefore, the successful manual release followed by a reapplication serves as a confirmation of the system's function during that process. Understanding this correctly highlights the importance of being able to assess the status of the braking system based on these actions.