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I just moved into a new house and it's wired for ethernet. There's a junction box that has a "Bridged Telecom Module TM-8" in it. My cable modem's phone jack is plugged into the "Line In" on that box and their are 8 slots all running to various ports in the house. All the jacks in the house are RJ45.

The problem is that I can't get a dial tone in any of the jacks. If I plug the phone directly into the modem it works fine but not when I plug into the outlet.

Anyway to test what's wrong? I'm a programmer and have some pretty basic electrical wiring knowledge but can't seem to figure out what's wrong.

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Have you tested all the ports? Are you sure there isn't an issue with a cable from the junction box to the punchdowns?

You really need to isolate one piece at a time for a wiring issue like this. Think of the setup in individual components:


Cable from Modem to Junction box

Junction box

Cable in wall

Jack/Punchdown at other end

Cable from there to phone


You already know the first 2 parts are OK based on your description of the original question. You can buy a cat5 tester pretty cheap ($30-100) and it may be worthwhile if you own a house wired for ethernet to have your own testing equipment.

Also what kind of phone are you using?

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