Yealink SIP-T48U Getting Started

Recovery Mode on Yealink IP phones
6
Using Recovery Mode and Runing Backup
System on Yealink IP Phones
This section introduces how to enter recovery mode and run the backup system on Yealink IP phones
step by step.
For Dual System Devices
This section is only applicable to SIP phone series including SIP-T42U, SIP-T43U, SIP-T46U, SIP-T48U,
SIP-T57W, SIP-T54W, SIP-T53W, SIP-T53, SIP-T53C, and VP59.
This feature can only be supported on new factory phones running firmware version 86 or later.
Procedures
1. Long press (Speakerphone key) and reconnect the power adapter to trigger the recovery
mode. Do not release until the recovery mode wizard appears on the phone LCD screen.
2. Press 1 to run the backup system.
Using Recovery Mode on Yealink IP Phones
(HTTP Server)
This section introduces how to perform recovery mode using the HTTP server on Yealink IP phones step
by step.
For SIP Phone Series
This section is only applicable to SIP phone series including SIP-T27G, SIP-T30, SIP-T30P, SIP-T31,
SIP-T31P, SIP-T31G, SIP-T33P, SIP-T33G, SIP-T41S, SIP-T42S, SIP-T46S, SIP-T48S, SIP-T58A,
CP960, and CP920.
This feature can only be supported on new factory phones running firmware version 86 or later.
Procedures

Yealink SIP-T48U Specifications

General

Handset type	Wired handset
Product type	IP Phone
Product color	Gray
USB 2.0 ports quantity	USB 2.0 ports have a data transmission speed of 480 Mbps, and are backwards compatible with USB 1.1 ports. You can connect all kinds of peripheral devices to them.
Expansion module support	Yes
Ethernet LAN (RJ-45) ports	2
Display diagonal	7 \
Display resolution	800 x 480 pixels
Lines quantity	- lines
Phonebook capacity	1000 entries
Number of VoIP accounts	16
Voice codecs	AGC, AJB, AMR-WB, CNG, G.711, G.722, G.723.1, G.726, G.729ab, VAD, iLBC
Security algorithms	AES, HTTPS, SRTP, TLS
Ethernet LAN data rates	10, 100, 1000 Mbit/s
Ethernet LAN interface type	Gigabit Ethernet
Front camera	-
AC adapter input voltage	100 - 240 V
Operating temperature (T-T)	0 - 40 °C
Operating relative humidity (H-H)	10 - 95 %
Keypad number of keys	29
Number of handles included	1 pc(s)
Harmonized System (HS) code	85171800

Weight and Dimensions

Width	226 mm
Height	185 mm