3 Ways to Diagnose Landline Phone Problems

Table of contents:

3 Ways to Diagnose Landline Phone Problems
3 Ways to Diagnose Landline Phone Problems

If your landline is not working, you should try to find the problem as soon as possible. You first need to find out if the problem is with one phone or more than one and find the devices connected to the line, from answering machine to fax, to find out where the problem is.


Method 1 of 3: Test a single phone without a dial tone

Diagnose Landline Phone Problems Step 1

Step 1. Unplug the device that is not working

Unplug the phone and the cable that connects it to the wall.

Diagnose Landline Phone Problems Step 2

Step 2. Find a working phone

Pick up another phone and check for dial tone. If none of the phones in the house have a dial tone, go to the next step.

Diagnose Landline Phone Problems Step 3

Step 3. Unplug the working phone

Take it out and unplug the telephone cable.

Diagnose Landline Phone Problems Step 4

Step 4. Plug in the phone that was not working

Plug it into the same jack as the phone that was working properly. Use the cable that was plugged into the phone that didn't work.

Diagnose Landline Phone Problems Step 5

Step 5. Verify that the dial tone is functioning correctly

If you hear the dial tone after plugging in the device, the problem is with the outlet. If there is still no dial tone, the problem is probably with your phone or the cord is not working.

Diagnose Landline Phone Problems Step 6

Step 6. Try a different bead

Before accusing the phone of anything, try a working cord taken from the phone that had a dial tone. If that makes the phone work that wasn't working, the problem was with the cord and you can easily replace it. If that still doesn't work, you're going to need a new phone.

Diagnose Landline Phone Problems Step 7

Step 7. Consider replacing the wall outlet

If the phone works on another outlet, it means that the first outlet has a problem. Most phone providers aren't going to take over the work, which means you'll have to fix it yourself or pay a technician to come and take a look.

There are many guides online that will help you replace and reconnect cables to a phone jack

Method 2 of 3: Diagnose a lost dial tone in all phones

Diagnose Landline Phone Problems Step 8

Step 1. Avoid doing this during a thunderstorm

If you lose dial tone during a thunderstorm, avoid using telephones. If lightning strikes your telephone system while you are fiddling with the cables, it could be fatal. If you lose a dial tone during a thunderstorm, you must wait for your telephone company to repair the lines that have been damaged.

Diagnose Landline Phone Problems Step 9

Step 2. Check every phone in the house

If none of the phones in the house have a dial tone, your provider may come and fix the problem. If some have dial tone, but the others do not, the wiring may have a problem and a technician should come and inspect it. This isn't going to be done for free by most vendors, which is why you are probably going to have to do it yourself or bring in a technician.

Diagnose Landline Phone Problems Step 10

Step 3. Make sure all phones are plugged in

If one of the devices has been unplugged for too long, the line may have been cut. Check all the phones and if you find one that's unplugged, you'll have to wait a few minutes after plugging it back in for the line to come back on.

Diagnose Landline Phone Problems Step 11

Step 4. Unplug the phones one at a time

Each time you unplug one, wait thirty seconds and check for dial tone on another phone. If you hear it, it means the last device you unplugged was the source of the problem. If you can't hear anything, plug the device back in and move on to the next one.

Diagnose Landline Phone Problems Step 12

Step 5. Find the DIR (Network Interface Device)

This is a box that is installed by the telephone provider when the technicians first come to install the cables. The DIR should be outside, where the cables enter the house, or it could also be inside, for example in the garage or a storage room.

  • Outdoor DIRs are usually found near electric meters or where cables coming from the street enter the house. This is usually a gray box, but it could also be painted the same color as the house.
  • Indoor DIRs are usually found in apartments and they may also have been installed in the kitchen. It should look like a bigger, more complex phone box.
Diagnose Landline Phone Problems Step 13

Step 6. Open the DIR by pulling the latch

You might need a flathead screwdriver to do this.

It is not necessary to open the interior DIRs to gain access to the test socket

Diagnose Landline Phone Problems Step 14

Step 7. Pull out the cable plugged into the test socket

In general, it should have a label that says, for example, "test socket", but this is not always the case. Most DIRs only have one test socket. On outdoor DIRs, you can usually find it at the top left of the box after opening it. On interior cases, it is along the bottom edge. Pull out the cable that is plugged into it at this time.

Diagnose Landline Phone Problems Step 15

Step 8. Plug a working phone into the jack

Connect a device that you are sure is working and its lead to the test socket. If you are not sure whether the device works, ask your neighbor if you can borrow one.

Diagnose Landline Phone Problems Step 16

Step 9. Listen for the dial tone

After connecting the device to the test socket, pick up the handset to see if there is a dial tone.

  • If you can hear it, it means there is a problem with the house wiring.
  • If you cannot hear it, you will have to contact your supplier and ask a technician to come, because that means there is a problem with the installed equipment.
Diagnose Landline Phone Problems Step 17

Step 10. Replace the test plug

Make sure you put the cable you used back in when you're done or you won't get a dial tone anywhere in the house.

Diagnose Landline Phone Problems Step 18

Step 11. Consider trying to do the repairs yourself

Telephone providers generally do not pay for in-home cable repairs. If you feel confident enough, you can try fixing the cables yourself. This is a big business for many people, but you will save the need for a technician to do the repairs. You will need to check the connection between the DIR and the wall outlets as well as the wall outlets themselves.

  • It only takes one that is malfunctioning for it to affect the others.
  • There are many guides online that will help you repair or replace telephone jacks in your home.
Diagnose Landline Phone Problems Step 19

Step 12. Contact the supplier for a problem with the DIR

If you do not have a dial tone at the DIR test socket, you must call a technician sent by your telephone provider. These repairs should be paid for, but you might have to wait a bit for someone to come and watch what happens.

If you cannot contact your provider because the phone is not working and you don't have a cell phone, you will need to make a call from your neighbor's phone or a pay phone

Method 3 of 3: Fix a noise problem on the line

Diagnose Landline Phone Problems Step 20

Step 1. Unplug the connected devices one at a time

The first thing you need to do to resolve a line noise problem is to unplug each device that is plugged into your phone line one at a time. This includes telephones, answering machines, modems, fax machines, computers with built-in modems, and alarm systems.

Diagnose Landline Phone Problems Step 21

Step 2. Observe the disappearance of the parasites

Every time you unplug a device, you should listen to whether there is still noise on the line. If they stop, it means the last device you unplugged was causing the interference.

Try to plug the device in question into a different outlet if possible

Diagnose Landline Phone Problems Step 22

Step 3. Test the outlet by plugging in a different device

The outlet itself may be the source of the interference and not the device connected to it. If the noise comes back after plugging in a different device, you are probably going to need to replace the outlet. You will also find guides on the Internet to help you install telephone jacks in your home.

Diagnose Landline Phone Problems Step 23

Step 4. Try changing channels on cordless phones

If you have static or other interference on a cordless phone, there may be too many signals on the same frequency. Find the Channel Tuning button on the handset or its base. Change the channel until you find one that is free of interference.

Diagnose Landline Phone Problems Step 24

Step 5. Move the objects that are causing the interference

Some electronic devices interfere with the frequency used by cordless phones, and you may get a clearer signal by moving or turning off these devices.

  • Avoid putting cordless phones in the kitchen, as microwave waves can interfere with the signal.
  • Wireless home networks that run on 802.11b / g use the same frequency as your cordless phones (i.e. 2.5 GHz). You may have to change your router to get one that works on 5 GHz. See How to Choose a Wireless Router for more information.
  • Baby monitors, Bluetooth devices and other cordless phones can also cause interference.


  • The DIR (network interface device) is a mostly gray box that is usually located outside the house, where the telephone cables leave, where the lightning protection system is installed and where it is located. terminate the telephone cables. The test socket with a short lead is one of the most important components of the DIR. If you unplug it, it also disconnects all internal cables from the telephone provider's network, allowing you to connect a well-functioning phone to the DIR to verify that there is a dial tone when service arrives. in your house. If so, the service is fine and it is the wiring or connected devices that does.
  • You could cause the line to lock up while you are testing. When you unplug the phone for too long, your phone provider may decide to automatically disconnect the service. This prevents the line from consuming resources that could prevent other users from having good quality service. Many problems with the line or devices can cause the provider to act as if you do not have a phone plugged into the line. When this happens, it could then be locked. This then implies that your line might not work for a few seconds after you find and fix the source of the problem.
  • If a phone stops working after a thunderstorm, the phone line may have been struck by lightning, which damaged the phones. Lightning could have fallen miles from your home and traveled all the way to your home.
  • Telephone lines for individuals and small businesses are generally installed by following one of the following installation diagrams:

    • each socket is directly connected to the DIR,
    • the wires coming out of the DIR go through a socket, before moving on to the next one and so on (it is sometimes called "looped" even if it is not a real loop since the last socket is not connected at the DIR),
    • a combination of the two: you could have several branches connected to the DIR that create different loops in the house or you could have one part of the network directly connected to the DIR and another part looped.
  • If the phone cannot dial a number, make sure there is no dial tone switch in the wrong position (for example, in the middle between two positions). Also note that the number dialing noise will not work with some VoIP services, and that the dial tone will not work on some landlines (although this is still quite rare now).
  • Phone providers often offer a cable maintenance plan. It usually covers repairs on substandard cables that no longer work properly. More importantly, this plan saves you from having to pay unnecessary "travel expenses" if the technician realizes the problem is inside the house. To be more precise, if it does not find a problem from the outside, for example if the dial tone is good at the DIR. It sounds like extortion, but it's better to pay it than not pay it: you're actually paying for the phone company to shut up, be nice to you, and help you out when you have problems. She rewards you by not blaming you for the problem.
  • If you think the phone is broken, ask a friend if you can take it home to test it on their line.
  • Make sure the ringer volume is high enough to hear it.


  • You could die from touching telephone cords during a thunderstorm. These cables come out of your house. Whether underground or above ground, they can be struck by lightning. Your telephone provider installs lightning protection outdoors, but the main purpose of these devices is to protect your network against "indirect lightning", that is, when it falls near you, but not directly on the line. If it were to fall directly on your lines, it could start a fire, cut your phone line, and even kill you if it happens while you are handling the phone or touching wires. If you must use the phone during a thunderstorm, you should use a cordless one or turn on the speakerphone, as phones plugged into the outlet can conduct lightning electricity to you.
  • It is possible to take an electric shock by touching the phone. You only need to touch cables or internal parts of the device once for this to happen. You might then receive an unpleasant (but usually not fatal) shock while you are working on the telephone wires, especially if it rings or someone dials a number (in the case of a rotary telephone) when you have your fingers on it. The discharge will be magnified if you stand on a conductive or wet surface, if you touch both wires at the same time, or if another part of your body comes in contact with a metal object, such as a pipe, pipe, freezer, etc.

Popular by topic