Yealink SIP-T42G - Manual (Page 125)

Troubleshooting
115
This chapter provides general troubleshooting information to help you solve the
problems you might encounter when using your SIP-T42G IP phone.
If you require additional information or assistance with your new phone, contact your
system administrator.
Why is the LCD screen blank?

Ensure that the phone is properly plugged into a functional AC outlet.

Ensure that the phone is plugged into a socket controlled by a switch that is on.

If the phone is plugged into a power strip, try to plug it directly into a wall outlet
instead.

If the phone is powered from PoE, ensure you use a PoE-compliant switch or hub.
Why does the phone display "Network Unavailable"?

Ensure that the Ethernet cable is plugged into the Internet port on the phone and
the Ethernet cable is not loose.

Ensure that the switch or hub in your network is operational.
Why doesn’t the phone display time and date correctly?
Check if you have configured the phone to obtain the time and date from the SNTP
server automatically. If the phone is unable to access the SNTP server, you need to
configure the time and date manually.
How do I find the basic information of the IP phone?
Press the OK key when the IP phone is idle to check the basic information of the IP phone,
such as IP address and firmware version. For more basic information, refer to
Phone
Status on page 14 .
How to obtain the MAC address of a phone when the phone is not powered on?
Three ways to obtain the MAC address of a phone:

You can ask your supplier for shipping information sheet which includes MAC
addresses according to the corresponding PO (Purchase Order).

You can find the MAC address in the label of carton box.

You can also find the MAC address from the phone’s bar code on the back of the
phone.