A lot of the time you don’t need any special tools, testers or training to diagnose trouble with your phones. Most of the time you won't even need a screwdriver. All that’s needed are a few minutes and a little common sense. You’ll be surprised at how much you can figure out and fix yourself at little or no cost. And if you can’t fix it, by investing a few minutes before calling for help, you can be reasonably sure that you’re calling the right people, and won’t waste time or money.

When diagnosing a malfunction, test every piece of hardware that is involved. You’d be surprised at all of the things that can be improperly manufactured, inadequately tested, or ruined by human contact. Anything can be made wrong, or messed up—even a phone cord. Things that people touch are more likely to get messed up than things that don’t get touched. Unless you have mice or a toxic waste leak, wires inside your walls should last 50 years, or longer.

#1 One of the most common dilemmas occurs when a phone line is dead or noisy, and you don’t know if it’s the fault of your own phone equipment, or of the company that provides your telephone service. If you call the service provider, and their technician decides (rightfully or wrongfully or even lazily) that the trouble was caused by a malfunction in your own equipment, you might get billed $75 for a false alarm, and you still have the trouble you had before.

Fortunately, there’s a simple solution.

(above) Most phone equipment, particularly in small businesses and homes, connects to the incoming lines at a demarcation point, also known as a “demark” or “network interface,” that is not much more than a heavy-duty assembly of one or more telephone jacks. They vary greatly in style and capacity and may be indoors or outdoors. The jacks should be labeled to indicate their phone numbers, and there’s a cord plugged into each one that leads to your phone gear. If you use VoIP phone service, you probably have an ATA (Analog Telephone Adapter) with jacks that connect to your phones. The ATA requires electric power.

When you have trouble, simply go the interface or ATA, find the jack for the problem line, and press the tab on the plug so you can temporarily remove it. Then you just plug in an ordinary analog phone. It doesn’t have to be anything fancy. It can be something that’s too ugly, dirty or bereft of features for your daily uses. The only requirement is that you know it works. If this test phone works properly when you plug it into the interface or ATA, you know the phone service provider is providing proper service, and you have to complain to the person who is responsible for maintaining your phones and wiring (which could be you).

If, on the other hand, your test phone sounds noisy, or you have no dial tone, or it doesn’t ring when called, you have found the phone service provider guilty. You can call them with confidence and not be intimidated.

#2 What do you do if the phone on your desk suddenly doesn’t let you hear other people, or doesn’t let people hear you? The solution could cost $350, $40, or 99 cents. You can probably find out without bringing in the expensive talent. Just swap some pluggable parts with a phone that works. The trouble is either with the base of the phone (maybe $50 - $350), the handset (probably under $40), or the handset cord (99 cents if you go to the 99 cent store).

Unless you smash your handset down when you hang it up, or drop it on the floor a lot, the repair will probably cost you 99 cents. Buy a few giant Tootsie Rolls while you’re at the store. The 99-cent cords will get you through an emergency, but you can get better quality, more lengths and more colors at

#3 What do you do if the phone is completely dead, with no lights, no display, no ring and no voice?

Here, too, you might get lucky and have a 99-cent solution. You might just have to replace the line cord between your phone and the jack on the wall. If that doesn’t do it, swap your phone with another one that works. If your “bad” phone is now a good phone, it’s time to call the phone fixer-upper, or get out your tools or buy a new phone.

NOTE: If your phone has features such as lights or a display that require electrical power, make sure that the power cord is plugged into an electrical outlet, and that the outlet is "live." Some "system" phones have lights and displays but do not use a power cord.)

NOTE ALSO: There’s a very good chance that any trouble you find will go away, without paying a penny for repairs, just by briefly unplugging it from the phone jack, and the electrical outlet, if it uses one.

This low-tech technique also works with computers, cordless phones, televisions, appliances, calculators, even cars. On the day I originally typed this paragraph, I used this method to restore operation of the icemaker and water dispenser in a GE refrigerator. I probably saved $125. Microprocessors can get confused, and like human brains, they often work better after a rest. Lots of “defective” products work perfectly by the time they arrive at the repair place. If the malfunctioning machine uses batteries instead of AC, pop them out for a little while. In a car, carefully disconnect a battery cable.

#4 Most traditional telephones with round, screw-on mouthpieces use “carbon granule” microphones that have not changed much over 100 years. They are inexpensive and reliable, but they have one problem. In humid weather, they can absorb moisture—just like salt or kitty litter—and the granules clump together. The volume of your voice is reduced and both you and the other person hear a tell-tale shooshing sound. There’s an easy FREE repair that anyone can do. Just take the handset and whack it on a hard surface, like a desk or a table, and the impact should separate the granules so you can have a normal conversation until the next deluge. It’s a good idea to protect the whacking surface with a magazine so you don’t damage the phone or the furniture.

#5 Alarm systems that call for help in case of a burglary, robbery, fire or flood are often connected to a phone line through a special 8-pin "RJ31X" jack that allows the alarm system to “seize” the line when needed.

This ability allows the alarm system to interrupt a phone call in progress to make a vital call to the alarm company or police; and also prevents an intruder from picking up a phone and stopping the alarm system from calling. When the alarm panel is plugged into the RJ31X, the phone line passes through the jack, into the panel, back out to the jack, and then to your phones.

If you lose phone service on the line that your alarm system uses, there’s a good chance that the alarm panel caused the problem. It’s easy to check—just unplug the cord from the alarm jack. If phone service comes back, call the company that maintains the alarm system.

There’s also a slight chance that the alarm jack itself is defective.

#6 Replace ALL of your handset cords every two to five years. Line cords should last much longer.