IBM 8671 - Eserver xSeries 235, Maintenance And Troubleshooting Manual

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Identifying problems using status LEDs
If the system-error LED in the operator information panel on the front of the server
is on, one or more LEDs inside the server or on the power supplies will be on. Your
server has LEDs to help you identify problems with some server components.
These LEDs are part of the light path diagnostics feature built into the server. By
following the path of LEDs, you can quickly identify the type of system error that
occurred (see “Light path diagnostics” on page 38).
Your server is designed so that any LEDs that are illuminated remain illuminated
when the server shuts down, provided that the ac power source is good and the
power supplies can supply +5 V dc current to the server. This feature helps you
isolate the problem if an error causes the server to shut down. See “System-board
LED locations” on page 53.
LEDs for Active PCI slots
Each Active (hot-plug) PCI slot has three LEDs associated with it: one power LED
and two attention LEDs. The following illustration shows the location of these LEDs.
PCI bus A error
LED (CR66)
PCI-X bus B error
LED (CR68)
PCI-X bus C error
LED (CR76)
PCI-X slot 5 power
LED (CR75)
PCI-X slot 6 power
LED (CR79)
PCI-X slot 5 internal
attention LED (CR73)
PCI-X slot 6 internal
attention LED (CR78)
PCI-X slot 5 external
attention LED (CR74)
PCI-X slot 6 external
attention LED (CR77)
Power LED
This LED is on when the hot-plug PCI slot has power. An adapter must not
be added to or removed from the PCI slot when the power LED is on.
When this LED is off, the hot-plug PCI slot has no power applied. An
adapter can be added to or removed from the PCI slot when the power
LED is off.
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xSeries 235 Type 8671: Hardware Maintenance Manual and Troubleshooting Guide