What occurs if the ST READY annunciator illuminates during engine start?

When the ST READY annunciator illuminates during engine start, it indicates that the engine is ready for startup, confirming that all necessary engine parameters and systems are functioning correctly. This light serves as an important cue to the pilot that conditions are optimal for engaging the starter, ensuring a smooth and safe engine start process. The readiness indicated by this annunciator implies that the external conditions and engine state are appropriately aligned for the starting sequence, thereby facilitating the successful initiation of engine operations.

The other options do not accurately represent the function of the ST READY light, as it does not indicate engine failure, confirm normal operation in a general sense, or require immediate pilot action—rather, it focuses on readiness for the specific action of starting the engine.