What should be done when track bulletins do not convey movement authority for passenger trains?

When track bulletins do not convey movement authority for passenger trains, identifying trains by train symbol is the appropriate response. This ensures that crew members and dispatchers have a clear understanding of which train is authorized to proceed on the tracks. Using train symbols helps maintain communication and coordination between different operational units and mitigates the risk of miscommunication regarding movement authority, which is crucial for maintaining safety on the rail network.

The other options do not address the need for clear identification and authorization necessary for safe train movement. Operating engines at a reduced speed may not guarantee that trains are properly authorized to proceed. Waiting for clearance before proceeding could lead to delays and impede service efficiency without resolving the authority issue. Checking all units before movement could be part of safety protocols but doesn't specifically clarify the requirement for movement authority in the absence of track bulletins.