Yealink SIP-T54S Administrator's Manual page 1026

Administrator's Guide for SIP-T2 Series/T19(P) E2/T4 Series/T5 Series/CP860/CP920 IP Phones
To reboot the phone via phone user interface:
Press Menu->Advanced (default password: admin) ->Reboot.
1.
The LCD screen prompts the following warning:
Press the OK soft key to reboot the phone.
2.
The phone begins rebooting. Any reboot of the phone may take a few minutes.
To reboot the phone via web user interface:
Click on Settings->Upgrade.
1.
Click Reboot to reboot the IP phone.
2.
The phone begins rebooting. Any reboot of the phone may take a few minutes.
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