Compex Systems Advanced SerialRAID Adapters SA33-3285-02 - Manual (Page 501)

Link Status (Ready) Lights
If a fault occurs that prevents the operation of a particular link, the link status lights of
the various parts of the complete link show that the error has occurred.
You can find the failing link by looking for the flashing green status light at each end of
the affected link. Some configurations might have other indicators along the link (for
example, SSA connector cards) to help with FRU isolation.
The meanings of the disk drive and adapter lights are summarized here:
Status of Light Meaning
Off Both SSA links are inactive.
Permanently on Both SSA links are active.
Slow flash (two seconds on, two seconds off) Only one SSA link is active.
If your subsystem has other link status lights, see the subsystem service information for
the subsystem for more details.
Chapter 18. SSA Problem Determination Procedures 481