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The Official Web Site of the State of South Carolina

Telephone Maintenance

As a telephone customer, you should be aware that repairs and maintenance to telephone wiring inside your home are your responsibility. Your telephone service provider is responsible for the Network Interface Device (NID), also called the Demark, and any outside wiring. The NID is a gray box located on the outside of the building where the telephone service is provided.

If you are experiencing problems with your telephone service, check the line before calling your local telephone service provider. If there is:

  • No dial tone on any telephones -- Locate the NID which contains a test jack. Plug a working telephone into the test jack. If there is a dial tone, then the problem is most likely a telephone set, jack, equipment, or inside wiring. If there is no dial tone, the problem may be the telephone line outside and you should contact your local telephone service provider.

  • Dial tone on some, but not all, telephones -- Plug a non-working telephone into a working jack. If there is no dial tone, then the problem is the telephone set. If there is a dial tone, then the problem probably involves inside wiring or a telephone jack.

If you report a telephone problem that the company finds to be on the customer’s side of the NID, you may be charged a fee. This flat fee may appear on your bill as a trip fee, trouble determination fee, or service charge.

Some telephone service providers offer a plan to cover inside wiring that would prevent being charged this fee. Names for such a plan include: Inside Wire Maintenance Plan, Home Maintenance Plan, and Inside Wire Protection Plan. The cost of subscribing to this plan usually appears as a monthly fee on your telephone bill. The amount of coverage a plan offers varies by telephone company. Make sure you understand how the plan works. For example, some plans prevent being charged a flat fee if the problem is inside wiring; however, they may not cover the cost of repairs. If you subscribe to a plan, contact your telephone service provider to make sure you understand how the plan works.

Your telephone service provider may also offer a plan that covers problems with your telephone equipment. Such a plan may be referred to as an Equipment Maintenance Plan or Telephone Protection Plan. The cost of subscribing to this plan also typically appears as a monthly fee on your telephone bill. Contact your telephone service provider for more information.