Yealink T40G Phone Manual

The Yealink T40G is a feature-rich SIP desktop IP phone designed for business environments. It features a 2.8-inch color LCD with 320x240 resolution, dual Gigabit Ethernet ports, PoE support, HD voice, wideband audio, 12 programmable line keys, integrated Bluetooth, dual-port headset support, and advanced call management features. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

1. Features at a Glance 2. Installation 3. First-Time Setup 4. Specifications 5. Controls and Settings 6. Connecting Devices 7. Advanced Call Features 8. Accessibility Features 9. Care & Cleaning 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Color LCD display, Handset, Base unit, Ethernet ports, Headset jack, Power adapter port.

FeatureDescription
Display2.8-inch color TFT LCD (320x240)
Network PortsDual Gigabit Ethernet (LAN & PC)
Power over EthernetIEEE 802.3af compliant
AudioHD voice, wideband audio, acoustic shield
Programmable Keys12 line keys with dual-color LEDs
BluetoothIntegrated Bluetooth 3.0
Headset SupportDual-port headset (RJ9 & Bluetooth)
CodecsG.722, G.711, G.729, iLBC, Opus
ProtocolsSIP, TCP/IP, UDP, RTP, RTCP, DHCP
SecuritySRTP, TLS, 802.1x

Installation

Unpack and inspect contents. Place on stable surface.

  1. Connect to network: Use Ethernet cable to connect LAN port to switch/router.
  2. Connect PC: Use second Ethernet cable from PC port to computer.
  3. Power the phone: Use PoE from switch or connect power adapter.
  4. Connect handset: Plug handset cable into RJ9 port.
  5. Connect headset: Optional headset connection to RJ9 port.

WARNING! Use only approved power adapter. Ensure proper ventilation.

First-Time Setup

Power on phone; follow on-screen prompts.

  1. Network configuration: Phone will obtain IP via DHCP automatically.
  2. Check network status: Press OK > Status > Network to verify IP address.
  3. Account configuration: Enter SIP server, username, password via web interface or phone menu.
  4. Test call: Make test call to verify configuration.
  5. Program keys: Assign functions to programmable keys via web interface.

CAUTION! Handle phone carefully; avoid liquid contact.

Specifications

Controls and Settings

Access menu via OK button or web interface. Front Panel: LCD, Navigation keys, Handsfree, Mute, Headset, Volume keys.

Key Functions: OK (enter menu), Navigation (up/down/left/right), Handsfree (speakerphone), Mute, Headset, Volume up/down, Message, Hold, Transfer, Conference, Redial.

Basic Settings: Language, Time/Date, Ringtone, Display contrast. Network: IP configuration, VLAN, QoS. Account: SIP server, authentication, codec selection. Features: Call forward, DND, auto answer, call waiting. Programmable Keys: Line keys, speed dial, BLF, call park.

Connecting Devices

Network: Ethernet cable to LAN port. PC: Ethernet cable from PC port. Headset: RJ9 or Bluetooth.

  1. Turn off phone before connecting cables.
  2. Match cables to correct ports (network to LAN, computer to PC).
  3. For PoE, ensure switch supports 802.3af.
  4. For Bluetooth headset, enable Bluetooth in menu and pair device.

Tip: Use quality Ethernet cables for best performance.

Advanced Call Features

Supports advanced business telephony features.

  1. Make call: Lift handset or press Handsfree, dial number.
  2. Answer call: Lift handset or press corresponding line key.
  3. Hold: Press Hold button during call.
  4. Transfer: During call, press Transfer, dial target, press Transfer again.
  5. Conference: During call, press Conference, dial second party, press Conference again.
  6. Call forward: Menu > Features > Call Forward > enable and set number.
  7. DND: Press DND key or menu setting to activate.
  8. Call waiting: Enabled by default; press Answer or ignore.
  9. Speed dial: Assign numbers to programmable keys.
  10. BLF: Monitor status of other extensions.

WARNING! Do not use phone during electrical storms.

Accessibility Features

Visual alerts: LED indicators for missed calls/messages. Audio adjustments: Volume control for handset, speaker, ringer. High-contrast display: Adjustable display settings. Headset compatibility: Supports hearing aid compatible headsets.

Care & Cleaning

Unplug before cleaning. Use slightly damp cloth; avoid liquids entering openings.

CAUTION! Do not use abrasive cleaners; keep away from heat sources.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits. CE marked. RoHS compliant. For support, visit www.yealink.com or contact your service provider. Copyright © Yealink Network Technology Co., Ltd.

Troubleshooting

SymptomPossible CauseCorrective Action
No powerPower source/cableCheck power adapter connection; verify PoE switch power; try different outlet.
No network connectionCable/DHCPCheck Ethernet cable; verify switch port; check DHCP server.
No dial toneAccount configurationVerify SIP account settings; check SIP server status; confirm registration.
Poor audio qualityNetwork/codecCheck network bandwidth; adjust QoS settings; try different codec.
Display issuesPower/settingsCheck power; adjust display contrast; reboot phone.
Bluetooth not workingPairing/distanceEnable Bluetooth in menu; re-pair device; ensure within range.

Reset: Press and hold OK during boot for factory reset (erases all settings).

Firmware Update: Web interface > Upgrade > upload firmware file.

Service: Contact service provider or visit www.yealink.com

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