A fault in a telecommunication line can be identified and located using line test data for that telecommunication line. A series of line tests can be performed on a selected telecommunication line experiencing problems. The results from the series of line tests can be analyzed to identify differences in the results between the line tests. The identified differences can then be used to determine if a fluctuation is present in the telecommunication line. If a fluctuation is determined to be present in the telecommunication line, the identified differences can also be used to determine a location of the fluctuation relative to reference location such as the distribution point where the telecommunication line originates.