DSL works, but I can't get a dial tone. Why?
August 31, 2008 7:16 PM Subscribe
No dial tone inside my house, but the DSL is working. When I plug a phone directly into the grey box (a.k.a. Network Interface Device) on the outside wall of the house, at the same time disconnecting the link from the phone company's incoming line to the wiring inside the house, I get a dial tone! It seems that the phone company is still providing service. The evidence is exactly what I'd expect if there were a phone off the hook inside the house... but there isn't. What else could be going on?
posted by aws17576 to technology (22 answers total) 3 users marked this as a favorite
For those who enjoy a good troubleshooting puzzle, here's the rest of what I know.
There are two wall phone outlets inside the house. Service to both originates in the same Network Interface Device. I can get DSL to work from either outlet, but I can't pick up a dial tone with a phone at either outlet. Calling my home phone number from a cell, I get a busy signal, again as though there were a phone off the hook. This remains true when any or all appliances (phones, DSL hub, and filters) are disconnected from the wall outlets. That seems to indicate that there isn't a problem with any of those appliances. Also, as I said above the jump, the phones in question work just fine when I connect them to the Network Interface Device.
When I break the link at the Network Interface Device, cutting off all service downstream (i.e. along the wall and into the house), I can call my home phone number from a cell and not get a busy signal -- I get an endless series of rings instead. More evidence that the trouble is somewhere downstream.
We have had a problem with mice, so it's possible that a wire was gnawed through. But this doesn't explain why our DSL is still working -- from both wall jacks I know about.
I feel like my experiments have ruled out every reasonable explanation for what's going on. Kind linemen and -women of MetaFilter, what have I not tried?