Consumers - T25: Troubleshooting Phone Connection

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T25: Troubleshooting Phone Connection

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How do I troubleshoot phone connection issues with my T25 Cable Modem?
If phone connection issues with the T25 arise, troubleshooting may resolve the issue, or may provide insight as to what is causing the issue.  This document describes how to troubleshoot phone connection issues with the T25.

The following troubleshooting steps are to be followed in sequence:
No Telephony Service
  1. ​If telephony service has not been activated yet, please call 1-800-Xfinity (1-800-934-6489) to setup an account that includes telephony service.   

    NOTE: If the current Comcast/XFINITY service is being migrated from a existing device, the current phone service and phone number will be transferred when the installation of the T25 is completed.


No Dial Tone
  1. Make sure all phones are on the hook and all cordless phone batteries are charged.
  2. If available, try to plug a working wired phone into different jacks to find out if the problem is isolated to one phone or one jack.
  3. If the Tel 1 LED is off, contact Comcast/Xfinity to activate the line or troubleshoot the phone service.
Not Receiving Calls
  1. Check the ringer on the phone to make sure it is turned on.
  2. If the phone rings a half ring on incoming calls, Call Forwarding may be activated. 
  3. Contact Comcast/Xfinity to troubleshoot the phone service.



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