IBM 7870B4U Service Manual page 33

Fault LED: When this amber LED is lit, it indicates that an error has occurred in
the expansion blade. The expansion blade error LED turns off only after the error
is corrected.
If an error occurs in the expansion blade, the fault LED on the blade device on
which the expansion blade is installed is also lit. Additional information about the
error is provided by the light-path LEDs in the expansion blade (see "BladeCenter
GPU expansion unit light path diagnostics LEDs" on page 188 for more
information).
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Chapter 2. Introduction