Christmas is coming, the lights have been strung on the tree and the front of the house...maybe even the yard. Then, seemingly for no reason, they flicker and appear to short out, or worse yet, the whole thing goes dark.

Here we illustrate situations which you have undoubtedly faced in Christmases past. Perhaps your solution was to toss out the "bad" strands and buy new lights; however, you could fix these problems quickly and easily. With this guide in hand, you'll save time and money by avoiding the need to replace "broken" light strands.

• A single strand of lights doesn't work.

• A single strand of lights doesn't work amongst the other strands.

• A strand of lights flickers on and off when moved or touched.

• A whole strand (or half a strand) starts to blink when it shouldn't.

• The whole strand works ... except for one single bulb.

• A replacement bulb is too big or too small.

• One bulb is brighter or dimmer than the rest on a single strand.

• Your Christmas lights come on at odd hours.

• No strand works when plugged into a certain wall outlet.

• All the lights were working, and now they don't.

• Your GFI circuit trips when it is reset, or for no apparent reason.

• How to replace a light bulb

• How to replace safety fuses

CHRISTMAS LIGHT CRISIS NUMBER 1

A single strand of lights doesn't work.

Here are several possible causes:
1. You have a bad plug connection.  See Cure No. 1
2. There's a bad fuse in the plug.  See Cure No. 2
3. There's a broken or missing bulb.  See Cure No. 3
4. You have a loose bulb.  See Cure No. 4
5. You have a damaged bulb.  See Cure No. 5

Remember: Most of these repair steps require that you have the strand plugged in to locate the problem. Unplug once problem has been located.

Cure No. 1 - A Bad Plug Connection
Step 1: Find the plug end of the non-working strand.
Step 2: Pull the plug out, then put it directly back into the wall outlet. Try this once or twice. If the lights come on, your problem is solved! We told you this would be easy!!

Cure No. 2 - a Bad Fuse in the Plug
Check to see if a test set works when you plug it into the socket of the strand which is not working. If the test set doesn't work, replace the fuse on the non-working strand.

Cure No. 3 - Broken, Missing or Abnormal Bulb
Check strands for broken, missing or abnormal-looking bulbs (they may have a black or mirror-like stain on the inside of the glass casing). Replace with care, as broken bulbs can shock you.

Cure No. 4 - Loose Bulbs
Use your fingertip to "flick" each bulb hard two or three times. (Individuals with delicate nails can use a pen or pencil.) Watch to see if the individual bulb or the entire strand flickers or flashes on. If this happens, you probably have a loose bulb. Carefully remove the bulb and check to assure that the center wire is centered on the base. If the center wire is damaged, replace the bulb. (Click here for help)

Cure No. 5 - Damaged Bulb
Take a pre-tested replacement bulb (the "good bulb"), remove the first bulb in the bad part of the strand and replace it with the good bulb. Chances are, this didn't work on the first bulb. However, continue replacing each bulb with the previous socket's bulb. (Remember ... every socket needs to have a bulb in order to attain a working strand.) You can also purchase a Light Tester which can help you find the damaged bulb.

CHRISTMAS LIGHT CRISIS NUMBER 3
A strand of lights flickers on and off when moved or touched.

Here are several possible causes:
1. You have a bad plug connection.  See Cure No. 1
2. There's a broken bulb.  See Cure No. 3
3. You have a shifted wire inside a light socket. See Cure No. 6

Cure No. 6 - A Shifted Wire in the Light Socket
Step 1: Lay the light strand on the floor with all lights on. Start at the first bulb on the end of the strand and lift it up six inches. Quickly and firmly run your enclosed hand along the wire and over the first three bulbs one to three times. Repeat this procedure on the next three bulbs, and so on, watching for the strand to flicker or flash.

Step 2: After determining which three-light section contains the bad bulb, lay the strand out so that it is not flickering. Take the first light of your three-light section and create a loop with the bulb at the top. Pinch the base of the loop with your fingers. Grasp the entire light (base and bulb) and gently roll it back and forth between your thumb and forefinger, holding the loop of wire steady. If it flickers, remove the bulb and check to see that the center wire is centered on the plastic base.

Step 3: Put the light back in. If you're lucky, the strand will not flicker. If it does, go on to the next bulb in your three-light section and repeat the procedure.

In our business, we have to repeat this cure many times. The tricky part is that sometimes we think we have found the shifted wire when actually we have found the bulb next to the one with the shifted wire (in moving the good bulb, the bad bulb next to it causes the lights to flicker, making us think that the good bulb is the bad bulb). Patience and perseverance pays off here, as we have found many times. If you're successful, there will be no waiting in the checkout lines at the store!

CHRISTMAS LIGHT CRISIS NUMBER 4
A whole strand (or half a strand) starts to blink when it should not be blinking.

Here are a few possible problems:

1. You have a broken or missing bulb.  See Cure No. 3
2. You have a "blinker bulb" in the strand.  See Cure No. 7

Remember: Most of these repair steps require that you have the strand plugged in to locate the problem. Unplug once the problem has been located.

Cure No. 7 - A Blinker Bulb in a Non-Blinking Strand
If no bulbs are broken, you will have to look for the "blinker blub" in the strand (which is clear except for a red-colored top, and some will have different-colored plastic bases). (Click here for help) Check the first and last lights first. If they aren't blinker bulbs, check the rest of the lights. When you find the blinker, replace it with a standard replacement bulb.

CHRISTMAS LIGHT CRISIS NUMBER 5
The whole strand works ... except for one single bulb.

Cure No. 8 - The Bad Bulb
This one is pretty simple. Chances are, the bulb is either burned out or broken. You'll need to remove it and put in a replacement bulb. Check to be sure that the new bulb is not too bright, too dim, too big or too small for the socket. (Click here for help) We suggest that you replace all non-working bulbs because doing so will increase the life of the other bulbs on the strand.

CHRISTMAS LIGHT CRISIS NUMBER 8
Your Christmas lights come on at odd hours.

Cure No. 11 - The Timer
A timer on your Christmas lights can be a safe and simple means of turning your lights on and off without your having to plug in or unplug strands. But if your lights turn on or off unexpectedly, check the timer and reset the clock. You might also check to see if you have plugged the timer into an outlet that is controlled by a light switch.

CHRISTMAS LIGHT CRISIS NUMBER 9
No strand works when plugged into a certain wall outlet ... or, all the lights were working, and now they don't.

Cure No. 12 - Switches, Circuits and Breakers

Step 1: If you are running your lights off of a timer, unplug the timer and plug your light strands directly into a wall outlet. Check to be sure that the lights are properly plugged in. If this doesn't work, check to see if a light switch that controls the outlet is turned on (most of these switches are located near exterior doors).

Step 2: If you are still in the dark, unplug the non-working strand and plug in a "test strand" (which you know works well) into the wall outlet. If it works, replace the fuse in the original strand. (Click here for help)

Note: If your house is newer or remodeled, you may have GFI circuits that must be reset when tripped. (See Christmas Light Crisis Number 10). Most GFI circuits can be reset simply by pressing the RESET button. In some homes you may have to reset it on your main fuse box. If your circuit has tripped a breaker in your main circuit box, one of the breaker switches will be out of line from the rest. Flip the switch all the way OFF to reset the breaker, then flip the switch back to the ON position. If GFI switches are designated in your fuse box, reset them. (It is not normal for any circuit to switch off. If the cause of the tripped circuit is not immediately obvious in the above situations, contact your local electrical power company for other possible causes.)

CHRISTMAS LIGHT CRISIS NUMBER 10
Your GFI circuit trips when it is reset, or for no apparent reason.

Blame it on the weather...or perhaps the lawn sprinklers. Either way, chances are that your outdoor light strands are saturated with water. (Click here for help)

Cure No. 13 - Try each of these steps until the problem is solved:

1. In bad weather, outdoor Christmas lights tend to trip GfI circuits. Wait until the storm is over before resetting the circuits. (If you need to use an inside GFI circuit, unplug the lights from the outside GFI and push the RESET button.) Note: if using a timer, it will need to be reset when you reset the GFI circuits.

2. Automatic or timed sprinkler systems can soak your light strands and trip the GFI circuit. Reset your sprinklers so that they come on when the lights are off (such as in the morning). Reset the GFI circuit (and the timer for your lights, as needed).

3. Check all light strands to be sure no lights or connecting ends are lying in water. Be sure to check lights that might be hidden by rain gutters, ground cover, etc. Allow wet strands to dry before resetting the GFI.

HOW TO REPLACE A LIGHT

Note: Do not throw away the bad or broken bulb you are about to change until your problem is solved. Be sure that the replacement bulb is not a blinker bulb, and that it is designed for your brand of lights (mixing different brands can cause bright or dim lights in the strand, or the plastic bases may not fit properly).

Step 1 - Use a piece of tape to mark the bad bulb, and unplug the lights.

Step 2 - Pull the bad bulb out of the socket by its plastic base.

Step 3 - Center each wire on the plastic base of the replacement bulb.

Step 4 - Align the base of the new bulb with the slot in the base of the socket, and push it in. It should be snug, but not too tight or too loose (in which case you may have the wrong-size bulb). Use the bulb that fits best.

HOW TO REPLACE SAFETY FUSES

Two types of fused plugs are used:

Replaceable Fused Plug - Designed to allow you to change the fuse inside the plug, saving the strand. We recommend these, as most come with extra replacement fuses.

Built-in Fused Plug - When the fuse goes, so does the strand. We advise against using this type of strand.

Most replaceable fused plugs have a sliding door over a small compartment in the plug. Simply open the door and replace the bad fuse with a new one. The importance of this difference will be obvious to you when the lights are strung on the tree or house and one strand blows a fuse. If the strand has a replaceable lug, you have an easy solution to getting the strand glowing again. However, you put up a strand with a built-in fuse, you will have to take down the entire strand and replace it.

Troubleshooting and Replacing Safety Fuses - First, check to see if a test set will work if it is plugged into the socket of the strand which you think has a bad fuse. If the test set doesn't work, replace the fuse. If it does, go back to the Table of Contents to check for another possible cause.

If the fuse blows again...

Look for punctured or exposed wires (this is a rare problem, but if you find exposed wires, either discard the strand or have it repaired by someone familiar with electrical work).

Check to see that fuses are not touching inside the plug.

Be sure the number of strands plugged together does not exceed the manufacturer's recommendations. If so, run an extension cord to the extra strands and plug them into it.