Cause : Cooling comes when the drive module temperature is excessive, it means that the temperature within the drive has reached levels that are higher than the safe operating limits. 

The A4A9 warning in your ABB ACS560 drive signifies a cooling alarm. This indicates that the drive's internal cooling system is not effectively removing heat, potentially leading to overheating of critical components.

1. Check ambient temperature. If it exceeds 40%/104 °F (frames R4… R8) or if it exceeds 50% /122 °F (frames R0…R8), ensure that load current does not exceed derated load capacity of drive.
2. Check drive module cooling air flow and fan operation.
3. Check inside of cabinet and heatsink of drive module for dust pick-up.
4. Clean whenever necessary.