Final answer:
A FAULT light on the HOT AIR pushbutton, accompanied by an ECAM caution message, signifies a malfunction in the aircraft's hot air distribution system, necessitating pilot intervention.
Step-by-step explanation:
When the FAULT light illuminates with an ECAM caution message on the HOT AIR pushbutton, it indicates a malfunction in the hot air regulation system of the aircraft's environmental control system. This could be due to a variety of issues such as sensor failures, valve malfunctions, or electrical problems within the hot air distribution network. Pilot action may be required to manage the temperature and airflow in the cabin, possibly by following ECAM procedures to troubleshoot and resolve the issue.
The FAULT light on the HOT AIR pushbutton, accompanied by an ECAM caution message, indicates a fault in the air conditioning system. It could be a malfunction, sensor failure, or any issue that requires attention. It is important to address the fault promptly to ensure proper functioning of the air conditioning system in the aircraft.