What does an Amber [OIL PX] annunciator indicate?

An Amber [OIL PX] annunciator specifically indicates that the oil pressure is within the range of 40 to 90 psi for a duration of 10 seconds while the engine is operating above idle. This status serves as a cautionary signal, suggesting that the oil pressure is at a level that, while not immediately alarming, may require the operator's attention to ensure it does not fall into an unsafe range. This is important for maintaining the engine's lubrication system and ensuring that it operates efficiently without the risk of damage due to insufficient oil pressure.

The other options do not reflect the purpose of the Amber annunciator. For instance, an oil pressure below 15 psi would typically trigger a more urgent warning, while pressures above 90 psi could indicate a potential malfunction.