176 Chapter 4 Troubleshooting209418-ANormal power-up sequenceIn a normal power-up sequence, the LEDs appear as follows:1 After power is applied to the switch, the Pwr (Power) LED turns on within 5seconds.2 The switch initiates a self-test, during which the port LEDs display variouspatterns to indicate the progress of the self-test.3 After the self-test, the remaining port LEDs indicate their operational status,as described in Table 43.Avvertenza: Per evitare lesioni fisiche dovute a scariche pericolose dicorrente, non rimuovere mai il coperchio superiore del dispositivo. Icomponenti interni non possono essere manipolati dall’utente.Table 43 Corrective actionsSymptom Probable cause Corrective actionAll LEDs are off. The switch is not receiving ACpower.Verify that the AC power cord is fastenedsecurely at both ends and that power is availableat the AC power outlet.The fans are not operating orthe airflow is blocked, causingthe unit to overheat.Verify that there is sufficient space for adequateairflow on both sides of the switch.Note: Operating temperature for theswitch must not exceed 40°C (104°F). Donot place the switch in areas where it canbe exposed to direct sunlight or nearwarm air exhausts or heaters.
