What should be done if the master controller is stuck in the ON position on a PA4 train?

In the event that the master controller is stuck in the ON position on a PA4 train, the appropriate action is to notify Control and adjust the control cut-out circuit breaker to OFF. This procedure is critical for ensuring safety during operations.

By notifying Control, you are making the appropriate personnel aware of a malfunction that could potentially lead to unsafe operating conditions or an accident. Their guidance may be essential for determining further actions and any necessary emergency procedures. Adjusting the control cut-out circuit breaker ensures that the train can be safely managed and is a preventive measure to avoid unintended movement of the train which could pose dangers to both passengers and crew.

The other options, while they may initially seem reasonable, do not adequately prioritize safety or proper protocol in responding to such a serious condition. Informing passengers, attempting to reset the controller, or continuing to operate the train from that cab could lead to greater safety hazards and is not aligned with standard operational procedures in such cases.