Cabletron Systems 520 - Manual (Page 77)

A-7
Problem Solving
Problem Solving Using the LEDs
When diagnosing a problem with the router, note that the problem is often
indicated by the states of the router’s LEDs. Table A-3 lists the states of the
LEDs for various error conditions that can occur during initial installation of
the device, along with probable causes and corrective actions to take.
Table A-3. LED States
Symptom Probable Cause Corrective Action
All LEDs are
off. The router does not
have power. Secure the power cables at the
back cover and between the
power supply and wall outlet.
Check the wall outlet using
another appliance or light, or
plug the power cord into
another outlet. If no power is
available, check the wall
outlet’s circuit breaker.
Replace the power supply or
the router if the problem
persists.
Wrong power supply. Ensure to use only the
H8767-AA power supply.
Power LED only
is off. Bad Power LED. Replace the router.
Module OK
LED is off. Self-test failed. If the LED does not light after
5 seconds, reset the router to
repeat the self-test.
Check console and reload
flash.
If the self-test fails again,
replace the router.
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