Zte Z718TL User Manual page 73

feature.
 Change PIN2: Change the PIN2 code for FDN access.
 FDN list: Manage the FDN list.
NOTE:
The PIN2 code is provided by your carrier. Entering an incorrect
PIN2 code more times than allowed can get your micro-SIM card
locked. Contact the service provider for assistance.
Set TTY Mode
Your phone is a TTY compatible device. A TTY device can allow
people who have hearing or speech disabilities to communicate
by telephone. Simply connect the TTY device to the phone's
headset jack.
Select a TTY mode for your phone to work with a TTY device, or
turn TTY off.
1. Touch the Home key >
field) > Settings > Call settings > TTY mode.
2. Select one of the following options. Consult your
teletypewriter manufacturer's manual if necessary.
TTY Off: Users who can hear and talk can disable TTY

support.
TTY Full: Users who cannot talk or hear may use this

mode to send and receive text messages through TTY
device.
TTY HCO: Users who can hear, but cannot talk, may use

this mode to listen to conversation of the other party, and
respond via text messages.
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