Yealink SIP-T27G Recovery Guide

Recovery Mode on Yealink IP phones
16
Procedures
1. Long press (Speakerphone key) and reconnect the power adapter to trigger the recovery
mode. Do not release until the recovery mode selection screen appears on the phone LCD
screen.
Note
2. Press 2 on the phone keypad to use USB flash drive.
The IP phone will read and upgrade the firmware from the USB flash drive.
After upgrading, the IP phone will initialize successfully and get ready for use. The LCD screen
prompts “Initializing…Please wait” when upgrading successfully.
3. If the IP phone fails to upgrade, the LCD screen will indicate the failure. You need to check and make
sure:
 The file system of the USB flash drive should be FAT32.
 The USB flash drive has been successfully connected to the IP phone.
 The resource files are correctly renamed and placed on the USB flash drive.
 Repeat the recovery mode procedures to try again.
The LCD screen prompts “Update failed (-1)” when failing to upgrade:
4. Press to verify the current firmware version after upgrading successfully.
Note
…. Update failed (-1) ….
Welcome
.... Initializing…Please wait ….
For CP920, you need to long press the specified soft key (the second from the left on the phone)
since there is no Speakerphone key.
Press 1 to use the TFTP server. For more information on recovery mode using the TFTP server,
refer to For SIP Phone Series.
You need to tap Settings->Status (for VP59/SIP-T58A IP phones) or tap Menu->Settings (for
SIP-T57W IP phones) to verify the current firmware version since there is no key.
1. TFTP
2: USB

Yealink SIP-T27G Specifications

General

Mounting	Desk/Wall
Handset type	Wired handset
Product type	IP Phone
Product color	Black, Gold
Wall mountable	Yes
Display diagonal	3.66 \
Display resolution	240 x 120 pixels
RJ-9 ports quantity	2
USB 2.0 ports quantity	1
Voice codecs	CNG, G.711, G.722, G.723.1, G.726, G.729, G.729ab, VAD, iLBC
Dual-Tone Multi-Frequency (DTMF) modes	SIP info
Lines quantity	8 lines
Phonebook capacity	1000 entries
Number of VoIP accounts	6
Bluetooth	-
Security algorithms	AES, MD5
Networking standards	IEEE 802.1Q, IEEE 802.1p, IEEE 802.1x, IEEE 802.3af
Ethernet LAN interface type	Gigabit Ethernet
Volume control	Digital
Operating temperature (T-T)	-10 - 50 °C
Operating relative humidity (H-H)	10 - 95 %
Cables included	LAN (RJ-45)
Number of handles included	1 pc(s)
Harmonized System (HS) code	85171800

Weight and Dimensions

Depth	210 mm
Width	265 mm
Height	170.5 mm