When inspecting passing trains, what condition must be reported?

Reporting overheated journals is crucial during the inspection of passing trains because these components play a vital role in the safe operation of the train. Overheated journals can indicate excessive friction or mechanical failure, which could lead to brake failures or even derailments if not addressed promptly. The identification of this issue is imperative for the safety of the train, crew, and anyone in the vicinity. Timely reporting allows for immediate investigation and remedial actions to be taken, ensuring all equipment continues to operate safely.

While engine paint condition might be of interest for aesthetic or maintenance tracking, it does not impact the operational safety of the train. Track cleanliness is important for smooth train operation, but it is not a direct indication of equipment failure or immediate safety concerns. Signal light color is critical for train operation and safety, yet it is related to the signaling system rather than the physical condition of the train itself. Thus, the requirement to report overheated journals directly correlates to mechanical safety and operational integrity, making it the correct choice in this context.