How to Troubleshoot a Motorola SBV5121 Cable Modem

The Motorola SBV5121 cable modem acts as a gateway between the local area network (LAN) and the Internet. A Motorola cable modem is preconfigured by your cable Internet service provider (ISP) to connect to its network and receive a public IP address. Sometimes, due to misconfigurations on the user side or the ISP side, the Internet connection does not work and needs troubleshooting. By following a few simple steps, the cable Internet connection can be back up and running with minimal effort.

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Step

Unplug the power from the cable modem.

Step

Unplug the power from a connected router, if present.

Step

Reinsert the power connector to the cable modem and wait approximately two minutes.

Step

Reinsert the power connector into the router, if applicable, and wait approximately 30 seconds.

Step

Check the "Cable" signal light on the front of the cable modem. If it is solid, test the Internet connection from a locally connected computer. If the light is blinking or absent, call your cable ISP for further assistance, as the problem is on your ISP's end.