IBM System x3950 Type 8878 Service Manual page 125

v Follow the suggested actions in the order in which they are listed in the Action column until the problem
is solved.
v See Chapter 3, "Parts listing, Type 8878 and 8879," on page 23 to determine which components are
customer replaceable units (CRU) and which components are field replaceable units (FRU).
v If an action step is preceded by "(Trained service technician only)," that step must be performed only by a
trained service technician.
Lit light path
diagnostics LED with
the system-error or
system-information
LED also lit Description
FAN A fan has failed or has been
removed.
Note: A failing fan can also cause
the TEMP LED to be lit.
PCI BRD The PCI-X board has failed.
CPU BRD The microprocessor tray has failed.
I/O BRD The I/O board has failed.
Action
1. Reinstall the removed fan.
2. If an individual fan LED is lit, replace the fan.
3. Reseat the microprocessor tray.
4. (Trained service technician only) Replace the
microprocessor tray.
1. (Trained service technician only) Reseat the PCI-X
board assembly.
2. (Trained service technician only) Replace the
PCI-X board assembly.
1. Reseat the microprocessor tray.
2. (Trained service technician only) Replace the
microprocessor tray.
1. Reseat the I/O board.
2. Replace the I/O board.
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Chapter 5. Diagnostics