Fujitsu BS2000 SE Series Basic Operating Manual page 64

CSS CSS and Global error indicator (yellow/orange)
Generally, the states of these indicators have the following meanings:
Do not light up when the MU is OK.
If the event is still acute after a power failure, the indicator is activated after the restart.
Light up when a prefailure event was detected. The indicator also lights up in standby mode.
Flash when an error was detected. The indicator also flashes in standby mode.
Irrespective of the color, when an indicator lights up or flashes this indicates an error event. Please notify
customer support.
LAN indicators
Figure 26: LAN indicators (MU M1)
Figure 27: LAN indicators (MU M2)
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