What should a train do if both external lights fail en route?

When both external lights fail while a train is en route, the appropriate action is to proceed over crossings at a reduced speed of 20 MPH. This response is grounded in safety regulations that prioritize the protection of the train crew, passengers, and anyone near the railroad crossings. The limited visibility that results from the failure of external lights compromises the ability of others to see the train, increasing the risk of accidents. Therefore, reducing the speed allows for a safer approach to crossings, granting more time to react if necessary.

In contrast, continuing at normal speed disregards the heightened risk due to loss of visibility. Stopping and waiting for repairs could lead to delays and is not practical unless safety warrants it. Meanwhile, notifying passengers of the malfunction, while it may be good communication practice, does not directly address the immediate hazard created by the absence of external lights. The primary focus in these situations is on maintaining safety protocols while ensuring that the train proceeds cautiously through affected areas.