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CDMA Call Settings

Use these options to enable hearing aid compatibility, and adjust several call settings, such as teletypewriter and DDTM.

  1. Tap home key > apps list icon > settings app icon Settings.
  2. Tap Call.
  3. Tap CDMA call settings.

TTY Mode

A TTY (teletypewriter, also known as a TDD or Text Telephone) is a telecommunications phone that allows people who are deaf, hard of hearing, or who have speech or language disabilities, to communicate by telephone.

Your phone is compatible with select TTY phones. Please check with the manufacturer of your TTY phone to ensure that it supports digital wireless transmission. Your phone and TTY phone will connect using a special cable that plugs into your phone’s headset jack. If this cable was not provided with your TTY phone, contact your TTY phone manufacturer to purchase the connector cable.

When establishing your Sprint service, please call Sprint Customer Service using the state Telecommunications Relay Service (TRS) by first dialing 7 key 1 key 1 key call key. Then provide the state TRS with this number: 866-727-4889.

To turn TTY Mode on or off:

  1. Tap home key > apps list icon > settings app icon Settings.
  2. Tap Call.
  3. Tap CDMA call settings > TTY mode.
  4. Tap TTY Full, TTY HCO, or TTY VCO. Tap TTY Off to turn TTY mode off.

Note: When enabled, TTY mode may impair the audio quality of non-TTY phones connected to the headset jack.

Warning: 9-1-1 Emergency Calling
Sprint recommends that TTY users make emergency calls by other means, including Telecommunications Relay Services (TRS), analog cellular, and landline communications. Wireless TTY calls to 9-1-1 may be corrupted when received by public safety answering points (PSAPs), rendering some communications unintelligible. The problem encountered appears related to TTY equipment or software used by PSAPs. This matter has been brought to the attention of the FCC, and the wireless industry and the PSAP community are currently working to resolve this.

DDTM Mode

Select this option if you want to direct all calls to your voicemail when you are using data connection.

Other CDMA Call Settings

Select these options to enhance voice privacy, prepend numbers automatically, or use plus code dialing.

  1. Tap home key > apps list icon > settings app iconSettings.
  2. Tap Call.
  3. Tap CDMA call settings and select or customize these options.
  • Voice Privacy: Select to enable enhanced privacy mode.
  • Automatic prepend: Select to automatically add "1" for long distance calls.
  • Plus code dialing: Tap to set plus code dialing. See Place and Answer Calls for details.