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3-1.3 Other Problems
Other specific problems may be diagnosed by using the LEDs, as below.
Power LED is off when the AC Power switch is ON:
• Defective power supply unit or fuse
• Incorrect AC voltage
• Defective Hub
Link/Act LED is off at any Fiber/TP port:
• Faulty node or wiring connection.
For fiber: the “TX”, “RX” cables should be paired at both ends
For TP:
a clicking sound should be heard when the RJ-45
plug is inserted in the STP RJ-45 jack
• No Link signal is received from the remote node/site
100Base-X Port at irregular traffic:
• Abnormal or invalid transmission status (mode / speed)
between local and remote link partners, i.e., full-duplex port is
connecting to a half-duplex port, or 10Mbps port is connecting
to a 100Mbps device.
Hub does not work:
If the hub does not work or is experiencing interference (e.g., your site
may be located near radio station or transmitter, etc.), try using shielded
twisted-pair (STP) cable instead of UTP cable.
Hub Diagnostic Test
• The switch hub performs a self-diagnostic test at major hub
modules upon power on, LED indicators will go to normal
status if no problem occurred.
• To reset or restart the hub, power off the hub and wait for 10
seconds, then power on it again.
