Phone Line not working but broadband active

[soms]

This could also be the result of an external line fault if you find nothing wrong with your extensions. At your master socket check for voltage across 2 & 5, should be roughly -50V DC. If you get no reading or a very low voltage then there is an external fault preventing you getting dial tone. From our own experience of such issues, ADSL will continue to work with only one leg, albeit the sync speed will be significantly lower.
::. Kitz - ADSL Line + Connection problems .:: - http://www.kitz.co.uk/adsl/connectionprobs.htm