Before working inside the server to view light path diagnostics LEDs, read the
safety information that begins on page vii and "Handling static-sensitive devices" on
page 33.
If an error occurs, view the light path diagnostics LEDs in the following order:
1. Check the operator information panel on the front of the server.
v If the information LED is lit, it indicates that information about a suboptimal
condition in the server is available in the BMC log or in the system-error log.
v If the system-error LED is lit, it indicates that an error has occurred; go to
step 2.
The following illustration shows the operator information panel.
Power-control button
USB connector
Power-on LED
Hard disk drive activity LED
Locator LED
2. To view the light path diagnostics panel, press the release latch on the front of
the operator information panel to the left; then, slide it forward. This reveals the
light path diagnostics panel. Lit LEDs on this panel indicate the type of error that
has occurred.
OVER SPEC
REMIND
Look at the system service label on the top of the server, which gives an
overview of internal components that correspond to the LEDs on the light path
diagnostics panel. This information and the information in "Light path diagnostic
LEDs" on page 105 can often provide enough information to correct the error.
3. Remove the server cover and look inside the server for lit LEDs. Certain
components inside the server have LEDs that will be lit to indicate the location
of a problem. For example, a VRM error will light the LED next to the failing
VRM on the microprocessor tray.
The following illustration shows the LEDs and connectors on the microprocessor
tray.
Information LED
Light Path
Diagnostics
PS
LINK
CPU
VRM
LOG
MEM
NMI
PCI
SP
DASD
RAID
TEMP
FAN
NONRED
PCI
CPU
I/O
BRD
BRD
BRD
Release latch
System-error LED
Chapter 5. Diagnostics
103