What should you do after receiving a hot bearing alarm and failing to locate a defect on the second unit?

When you receive a hot bearing alarm and are unable to locate a defect on the second unit, the correct action is to set out the indicated locomotive. This response is critical for ensuring the safety of the train, passengers, and crew. A hot bearing can lead to serious equipment failure, including the risk of a fire or derailment. By setting out the locomotive, you mitigate these risks immediately rather than continuing on a potentially unsafe path.

Setting out the indicated locomotive allows for an in-depth inspection and maintenance once the train is stopped. It also helps ensure that any further issues, such as heat-damaged components or subsequent failures, do not affect the functionality and safety of the remaining train cars. This proactive measure is in line with best practices for operational safety and maintenance.

Other options, while they may seem viable, do not adequately prioritize safety. Continuing the trip or proceeding at reduced speed can lead to more severe consequences if the issue is indeed significant. Stopping to inspect all units could be excessive if the hot bearing alarm specifically indicates a problem with the indicated locomotive alone.