LED Status Description
System Status Flashes green and red
alternately every 0.5
seconds
• The drive is being formatted.
• The NAS is being initialized.
• The operating system is being updated.
• RAID rebuilding is in progress.
• Online RAID Capacity Expansion is in progress.
• Online RAID Level Migration is in progress.
Red • The drive is invalid.
• The disk volume has reached its full capacity.
• The disk volume is about to reach its full capacity.
• The system fan is not functioning.
• An error occured when accessing (read/write) the data.
• A bad sector is detected on the hard drive.
• The NAS is in degraded read-only mode (two member
drives failed in RAID 5 or RAID 6 but the data can still
be read).
• Hardware self-test error
Flashes red every 0.5
seconds
The NAS is in degraded mode (one member drive failed in
RAID 1, RAID 5, or RAID 6).
Flashes green every 0.5
seconds
• The NAS is starting up.
• The NAS is not configured.
• A drive is not formatted.
Flashes green every 2
seconds
The NAS is in S3 sleep mode.
Green The NAS is ready.
Off All drives are in standby mode.
Drive/SSD Flashes red The drive is being located.
Red A drive read/write error has occurred.
Flashes green The data is being accessed.
Green The drive can be accessed.
Off No drive is detected.
M.2 SSD Flashes red The drive is being located.
Red A drive read/write error has occurred.
Flashes green The data is being accessed.
Green The drive can be accessed.
Off No drive is detected.
TS-x73U User Guide
Basic Operations 47