How to Find a Short in a Phone Line

By Neal Litherland

Homeowners have a few options when trying to locate a telephone short.
i telephone electric pole image by jimcox40 from

When your phone line shorts out, it can be a major inconvenience. Fortunately there are some steps you can take to identify the location of the short. However, if you have minimal experience with electronics, it might not be safe for you to diagnose individual lines or to replace shorts in the electrical system yourself.

Plug in a different telephone, preferably a telephone with a cord, to make sure that the short isn't just your original phone. The use of a corded telephone may also reset some systems and eliminate the problem.

Plug the telephone into other phone jacks in your house to see if the short is in just the phone jack you were using. If the problem persists then you can be assured it's beyond the single connection.

Locate the exterior test box where the line from the telephone connects to your house. Unplug the jack from the exterior line and plug it into your phone. Try to make a call from your phone. If the phone works, then the problem is inside your house. If not then the problem is external and the phone company will need to fix it.