AT&T West → No dial tone but DSL works

Last Friday suddenly after making a call, we suddenly lost dial tone in our phone. However, we do have a dial tone at the NID and can make phone calls if a phone is connected to it but the moment any internal lines are attached to the phone line, dial tone goes away. I tried a splitter at the NID with one line going to a phone and another to the inside line and the dial tone went away. As soon as I unplugged the internal line, dial tone came back. In all cases, DSL works great. We have a relatively new house and the entire house was wired for data and phone line using CAT5 cables. I did some cursory look at the cables and nothing seems out of ordinary. I went and bought a cheap telephone line tester that when plugged into a jack gives you green/red signal to try to see if any of the jacks are bad. All of them seem to test OK. As far as I can tell, we don't have any other equipment/phone attached to this line.

I am completely clueless now as to how to proceed further. Any advice will be very helpful. Where does go about finding a person to help fix this problem. I am in the SF bay area (San Jose).

Thanks.

The internal wiring has a weak short. Basic electrical troubleshooting by segmenting the internal wires can be used to locate the short.
If you pay ATT the monthly wiremaster fee, call 611 and schedule a repair call. Otherwise pay someone with basic electrical skills to make the repairs.

I had this problem too. The reason was that there was enough leakage between the tip
and ring (the phone line which carries audio) that the phone was effectively off hook.
It was as if someone was using a phone. However the short , due to wet weather, was
not enough to kill the DSL connection.

I suspect this is probably the only reasonable way your and my problem could happen.

IF you go to the box farthest away from your house line that you can get into you should
disconnect the line which goes to your house. If you have a voltmeter measure it
first and you will see less than 48 volts. Once you disconnect the wires that lead
to your house you should see the voltage where the wires to your house were go up
to about 50 volts DC. Don't accidently disconnect the wires leading from the phone
company. They will probably be a heavy black wire which you can see coming from
a pole or if you have underground wiring then you'll simply have to be careful to
keep track of 4 wires. Two from the phone company and two leading to your house.

The two from the phone company bring 50 volts DC to your house via the wires
which also go to terminals in the box. At this point your wires are called 'inside
wiring'. On the other side the phone company is responsible for the signal.

It's really very simple. If you're confused it's probably due to my explanation.

There's not enough current to light a light bulb so don't try testing the 50 volts
with a light. You'll need to use a voltmeter of some kind that measures 50 volts.

IF the line rings when you're testing it you'll see about 100 volts AC.

When you pick up the phone and all is hooked up the voltage drops to
about 8 volts or less. If you measure first and see 5 to 10 volts DC then
it's likely that a phone or answering machine is off the hook. Lower than
about 5 volts DC and there's some other problem. 0.00 volts means a
dead short. Unlikely. I suppose at about 20 volts the phone company
might think a phone was off the hook. This 20 volts would signify
a partial short due to what I said before. Water / moisture causing
a partial short.

This is why you measure and then disconnect your side of the phone wiring
to determine if the problem is on your home side or the phone company's side.

If it's on your side then check to see if you have inside wiring coverage in
your home service. Cost is about $5. / month. If not then get a friend to
help you diagnose the problem.

If you do have inside wire coverage then the phone company will come
'for free' , you pay for it at $5/mo in your bill, and fix the problem.

One test would be to disconnect all of the phones, answering machines
and test the line with a known good phone to see if the tone comes
back or if the voltage comes back to 50 volts when no phones are
on the line.

The DSL modem does not cause the line voltage to drop to less than
the regular , about, 50 volts DC as far as I know.*

Good luck

*someone might correct me if the modem does cause a voltage drop on a phone
line. I never have tested it.

blah.
att is becoming shit now.

thank god.

i am switching back to CABLE .. again

and also they have 10MB and 16 MB interenet .

ATT at my area only got 6 ..
its been annoying with all the d/c and shit happening.

BYE BYE ATT.. hope you get better and also have more faster speed except purchasing U-VERSE when i don't need the tv.

Thanks to everyone who replied. It turns out there was a weak short. An unused phone line was somehow messing up the phone connection. I had to call someone who had all the right tools to fix the problem. He came was able to fix it within 15 minutes.