Allied Telesis AT-8400 Series Reference Manual page 109

AT-8400 Chassis Installation Guide
❑ This could be one of three issues: the fans for the power supplies
may have failed, the management card may be experiencing a
fault, or the power supply may have failed. If one of the power
supplies has failed, you can confirm this by loading three or more
line cards into the chassis. If the fault LED on the power supply
turns OFF and the POWER LED turns steady green in response to
loading the line cards into the chassis, then the power supply fans
may have failed. You can confirm this by looking at the FAN A and
FAN B LEDs on the management card. If the FAN A or FAN B LEDs
turn steady amber, then the fans have failed. For troubleshooting
information about the management card, see Troubleshooting
the AT-8401 Management Card on page 91. For troubleshooting
information about power supplies, see Troubleshooting the
Power Supplies on page 93.
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