Chapter 3: System Interface
3-3

Overheat/Fan Fail/UID LED

When this LED ashes it indicates a fan failur e. When continuously on (not ashing)
it indicates an overheat c ondition, which may be c aused by cables obstr ucting the
air ow in the system or the ambie nt room tem peratu re being t oo warm.
Check the routing of the cabl es and make sur e that all fan s are prese nt and op -
erating normally. Also check to ma ke sure that the air s hrouds are in stalled an d
that the top cover is on. Finally, verify t hat the he atsinks ar e insta lled pr oper ly.
This LED will remain ashing or on as long as the overhe at condition exists. When
used with a UID-compatible motherboard, the UID function is used to turn on or off
the blue light function of the the LED. Once the blue light is activated through the
system software, the unit can be easily located in very large racks and server banks.

3-4 Hard Drive Carrier LEDs

Each hard drive carrier has two LEDs.
Green: When illuminated, the green LED on the front of the drive carrier in-
dicates drive activity. A connection to the SATA backplane enables this LED to
blink on and off when that particular drive is being accessed.
Red: The red LED indicates two states. When blinking, it indicates the drive
is rebuilding. When solid, it indicates a drive failure. If a drive fails, you should
be noti ed by your system management software. Please refer to Chapter 6 for
instructions on replacing failed drives.