Ensuring the modem is connected properly

Updated: 11/13/2018 by Computer Hope

It is common for computer modems to not be connected properly either because of improper setup, a cable becoming loose, or someone disconnecting the cable to be used elsewhere. We have listed several items to check to help ensure that the modem is properly connected.

Two phone holes

Modems today have two phone holes that allow a phone connection to be connected. Connecting the modem to the improper hole prevents the modem from working. When inspecting the back of the modem, you have either text or a picture describing the phone and modem hole. The cable coming from your wall should be connected to the line, line in, or Telco hole or the hole that does not have a picture of the phone next to it. The other hole allows a phone to be connected to the same line and can be used to check for a dial tone. In the picture below is an example of an internal modem with the two RJ-11 connections on the back.

Internal modem

Special splitters

Some older modems may require that you connect a splitter into the modem itself. If your modem or computer included a splitter, it is recommended that it be used in case it is required. A splitter only applies to modems that have one connection on the back of the computer. If your computer modem does require a special splitter, it can only be obtained from the computer or modem manufacturer; a standard splitter will not work.


The standard phone hole for a modem is referred to as an RJ-11 connection. Many computers today also include a network card, which utilize an RJ-45 connection, which is extremely similar to the RJ-11 connector, but is slightly bigger. Ensure that if you have a network card and modem that you are connecting it into the correct hole. Also, make absolutely certain that you have a Modem in the computer and not only a network card. Newer computers and laptops may not included a modem.

Analog vs. digital

If you cannot get your modem to work, verify that the line you are connecting to is an analog connection. Many hotels have digital phone jacks that are not compatible. If this is the case a special connector will be required to convert digital to analog. These connectors can sometimes be purchased at the hotel or a local Radio Shack.

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