HP 2520g-poe User Manual

4-4

Troubleshooting
Diagnosing with the LEDs

Diagnosing with the LEDs

Table 4-1 shows LED patterns on the switch that indicate problem conditions 
for general switch operation troubleshooting.

Table 4-2 shows LED patterns that indicate problem conditions for PoE 
troubleshooting.

LED patterns for General Switch Troubleshooting

1.

Check in the table for the LED pattern you see on your switch.

2.

Refer to the corresponding diagnostic tip on the next few pages.

Off with 

power cord 

plugged in

1

1

1

1

On

Prolonged On

Prolonged On

1

1

On

Flashing

2

Flashing

2

1

1

On

Flashing

2

Off

Flashing

2

1

On

Flashing

2

Flashing

2

1

Flashing

2

On

Off

Off

1

Off with cable 

connected

On

Off

Off

1

On, but the port is not 

communicating

1

This LED is not important for the diagnosis.

2

The flashing behavior is an on/off cycle once every 1.6 seconds, approximately.