Chapter 3: Installing your T25
Use your hand to tighten the connectors to avoid damaging them.
3. Connect the Ethernet cable to the
Ethernet
port on the rear of the T25.
4. Connect the other end of the
Ethernet
cable to the Ethernet port of the device (e.g.,
laptop, desktop) you will be using to activate your T25 (see
(page 19)). You can then use the same Ethernet cable to connect your
Wi-Fi Router to the T25.
5. Connect the power cord to the
Power
port on the rear of the T25.
6. Plug the other end of the power cord into an electrical wall outlet that is not controlled
by a wall switch.
This automatically powers ON and connects your T25. During startup, the Power and US/
DS (Upstream/Downstream) LEDs will FLASH and then light up SOLID white.
Note:
During startup, if the LEDs continue to blink, it means the device is
receiving a firmware upgrade. This may take 5-10 minutes and the T25 will reboot
several times in the process.
Connect your telephone
If you are migrating your current XFINITY service from an existing device, your current phone
service and phone number will be transferred to your T25 when the installation is finished.
Please note that if you do not currently have Telephony service from Comcast, call
1-800-
Xfinity (1-800-934-6489)
to set up an account that includes Telephony service.
1. Connect the telephone cord (not included) to the
TEL LINE
port on your telephone.
2. Connect the other end of the telephone cord to the
TEL 1
port on the rear of the T25.
3.
Optional:
For a second telephone, connect a telephone cord of a single-line telephone
to the
TEL 2
port on the rear of the T25.
4. Check to confirm that your telephone has a dail tone.
Note:
For an Alarm System connection with a single telephone line, connect
the Alarm Panel to the Tel2 port. If both telephone lines are providing telephony
services, use an RJ-31X adapter (not included) on the Tel1 port.
Establish an Internet connection
Once the Power, US/DS, and Internet LEDs are lit SOLID white, you are ready to establish an
Internet connection. Activate the T25 with Comcast and provide the Serial Number and the
MAC address. You can find the Serial Number and the MAC address on the unit label at the
bottom of device or in the Quick Start Guide.
If you do not currently have Xfinity service or Xfinity Voice service, contact the Customer
Support to create an account.
If you already have Xfinity service, perform the following:
1. Open a web browser on a laptop connected to the T25, or on a mobile device with
Internet access.
SURFboard
®
T25 Cable Modem with Xfinity Voice User Guide STANDARD Revision x.5
19
