Cause : HW fault on optional boards comes when a hardware fault has occurred when accessing an optional board. This means a malfunction was identified within an optional board that's not essential for the core functionality of the drive.

The F045 fault in Siemens Masterdrive indicates a hardware fault detected on one of the optional boards connected to the drive.

1. Replace CU, or replace the unit (Compact PLUS).
2. Check connection of the board subrack to the optional boards and replace if necessary.