IBM System Storage DCS9900 1269-3S2 Storage Expansion Unit Installation, Service, and User Guide
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4.4.5 Thermal Shutdown
The enclosure system will shut down when a critical temperature threshold is exceeded in order to
prevent permanent damage to the disk drives.
Symptom
Cause
Action
1
ALL AMBER LEDs
on the Ops Panel
and on ALL drive
bays illuminated
flash.
2
Audible Alarm
sounds almost
continuously and
cannot be muted.
At a higher threshold than the
Thermal Alarm (this should
already have been activated),
the enclosure is programmed to
shutdown in order to protect
itself and the disk drives from
damage.
OR - All fans have failed.
OR - Only 1 fan operating and
the internal temperature is 40° C
or above.
1
Check for airflow restrictions.
2
Check Power Supply/Cooling
module faults.
3
Check for excessive local
temperatures.
Important
The Enclosure will SHUTDOWN 10 seconds after the above symptoms are
observed. This will leave the following indications active.
1
FAULT LED
illuminated AMBER.
2
Enclosure powered
off.
1
Clear the source of the overheating.
2
Leave for a period to cool down.
3
Remove AC power from the enclosure for at least 30 seconds to reset
the shutdown condition.
4
Re-start enclosure using normal operating procedure.
5
Check for re-occurring cooling faults (especially fan failure).
