Allied Telesis AT-8288XL/SC - Manual (Page 50)

Troubleshooting
50
Common Problems
This section lists common possible sources of errors and the actions
required to correct them.
Link /Activity
LED on Any Port
is OFF
This can indicate:
# A loose data cable.
# The device at the other end of the connection is powered OFF.
# The 10/100Base-TX data cable is not wired correctly (straight/
crossed) for the device.
# The port’s selected transmission mode does not match that of the
attached device.
Perform the following steps in sequence; you need not proceed to the
next step if the problem is resolved:
1. Make sure the data cables are secure.
2. Make sure the device at the end of the connection is powered ON.
3. Make sure the 10/100Base-TX data cable is wired correctly
(straight/crossed) for the device.
4. Logon to Omega if you can and check the port status ( Port
status and configuration> menu).
If the port is Enabled, make sure the transmission speed
matches that of the connected device (auto-negotiating, full-
or half-duplex).
5. Contact Allied Telesyn’s Technical Support for assistance.
Power LED is
OFF
If there is no power to the switch, it cannot function.
A Power LED that is OFF can indicate:
# A loose power cord.
# Power supply failure, malfunction, or loss of power to the power
supply.
# A power supply voltage below acceptable levels.
# A high switch temperature due to fan failure or extreme ambient
temperature.