IBM QS22 - BladeCenter - 0793, Service Manual

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The location of each LED on the system board is shown in the table below.
Table 5. System board LEDs
LED Color
Board
location Explanation Comments
Status LEDs The status LEDs are listed
for reasons of completeness
since they are for use by
IBM service only and are not
normally visible. They are
not activated by the light
path diagnostics switch.
Heartbeat Green D16 Indicates the BMC is functional.
Alert Yellow D15 Indicates an error condition has
occurred on the system board.
Ethernet 1 activity Green D12 Indicates on-board Ethernet 1 is
active and sending or receiving
packets.
Ethernet 0 activity Green D11 Indicates on-board Ethernet 0 is
active and sending or receiving
packets.
BE0_PLL_LOCK Green D8 Indicates the phased lock loop of
Cell BE-0 is working.
BE1_PLL_LOCK Green D13 Indicates the phased lock loop of
Cell BE-1 is working.
MM_SELECT_A Green D19 Indicates Advanced Management
Module A is active.
MM_SELECT_B Green D18 Indicates Advanced Management
Module B is active.
1
1
Temperature fault LED
System board LED
CPU fail LED
NMI error LED
I/O buffer DIMM error LED
I/O buffer DIMM error LED
Light path
diagnosis
switch
Light path
diagnosis
LED
Modular
flash drive
error LED
System memory DIMM
error LEDs
Figure 27. Light box and system board LEDs
Chapter 5. Diagnostics and troubleshooting
59