jtpryan wrote:
For some reason I have lost 1 of my 2 phone lines on the second floor.
This would be the yellow/black pair. If I am correct, the jacks on
the second floor start with the one in my bedroom. Directly below
this is my office, which works. I don't understand why this would
happen, I have done nothing to the jack in my office, it has never
been out of the wall. So, I want to test for continuity between
these two points. I don't have a tone generator, and don't want to
buy one just for this. I'm wondering if anybody has another idea
short of running a long wire from upstairs to downstairs.

Thanks,
Jim

Connect the yellow to the black upstairs.

Measure continunity between the yellow and the black downstairs.