Final answer:
GPWS PANEL FAULT light on the SYS pushbutton of the GPWS PANEL indicates a system malfunction or failure, requiring immediate action by the flight crew per standard operating procedures.
Step-by-step explanation:
The GPWS PANEL is a critical component in an aircraft's safety system, known as the Ground Proximity Warning System. When a pilot sees a FAULT light illuminated on the SYS pushbutton, it typically indicates that there is a system malfunction or failure in the GPWS. The GPWS is designed to alert pilots of potential terrain conflicts that could lead to an accidental ground collision.
The FAULT light specifically suggests that the system is not operating as intended, which could be due to various reasons such as sensor failure, data corruption, or a power issue.
Once the FAULT light is lit, it is essential for the flight crew to take immediate action by following the standard operating procedures, which often include referencing the aircraft's checklist, notifying air traffic control if necessary, and preparing for alternative safety measures if the system cannot be restored to functional status.