What signal must be reported when it is not functioning correctly?

The requirement to report any light that does not conform is based on the importance of maintaining safe and reliable train operations. Signals play a critical role in guiding train movements, indicating aspects such as speed, stopping points, and track conditions. When a signal is malfunctioning—in this case, when any light does not conform to what is expected—it can lead to confusion and can compromise safety.

A non-conforming light can indicate that the signal is not presenting the correct information to train operators. This could cause a train to operate under unsafe conditions or lead to incorrect actions being taken by the crew. Therefore, immediate reporting of such a malfunction is crucial for ensuring that maintenance crews can address the issue and restore proper signal functionality without delay.

Other options, while relevant to operational safety, do not directly address the immediate reporting of a malfunctioning signal. For example, the next passing signal and the condition of adjacent tracks are important to monitor but are not directly related to the specific malfunction of a signal light. Reporting the train's current position aids in operational awareness but does not pertain to the issue at hand with the signal's functionality. This focus on non-conforming lights ensures that safety protocols are upheld, preventing incidents that could arise from a failure to report such critical information