Cortelco 2757 - Manual (Page 56)

56
4 Troubleshooting
If your 2757 is not working properly, please check this troubleshooting checklist.
Scenario / Problem Solution
Nothing is displayed
on LCD screen
Is the AC adapter plugged into an electrical
outlet?
Is the AC adapter connected to the 2757?
If using PoE, check the PoE switch and the
Ethernet cable.
Check contrast setting.
I see malformed /
strange text
displayed on the LCD
screen of IP Phone
Disconnect the power cord and Ethernet
cable, and reconnect after 10 seconds.
I can not hear
dialtone
Replace the cord between the 2757 and the
handset with a new one.
Press ‘SPEAKER’. If dialtone is heard,
replace the handset.
Check the volume setting. Try increasing it.
I can hear dialtone in
the handset, but I can
not place / accept
phone call
If busy tone is heard in the handset, the
remote party may be busy, not online, or not at
the dialed number. Try the call again later
and make sure the phone number is correct.
If ‘Initializing SIP server…’ is displayed on the
LCD screen, please check the network
connection. If there is no problem with the
network connection, contact the service
provider.