How to Find a Bad Bulb on Christmas Tree Lights

Detangling your Christmas tree lights is the second worst thing about the holiday season. The first-place winner? When you’ve gone through all that hassle, undone all the knots and kinks, and you plug in your beautiful lights to find them totally dead. 

Hours of work for nothing. Plus, you then have to brave the cold weather, crowded stores, and close calls in the parking lot to get new strands of lights. (Or you just buy them online, but it’s still a hassle.) 

We want to take the stress out of your holiday season. So, let us give you an early Christmas gift! Follow these steps to find a bad bulb on your Christmas tree lights.

Step 1: Check the Outlet

First, make sure your lights are really plugged in. (We know it’s silly, but we’ve all done it!) If you’ve plugged in your lights and nothing happened, unplug them and plug another appliance into the outlet. If that appliance doesn’t work either, find your circuit breaker and check for a flipped switch. You can also test the outlet with a circuit tester.

Step 2: Check the Wires

You might have noticed this when you were doing all that untangling, but check again. Look for any broken strands with wires poking through them. If you find any, it’s time to toss the lights and get a new set. If you don’t want all your hard work to go to complete waste, you can take off all the bulbs to use as replacements in the future!

Step 3: Check the Fuse

Christmas lights usually have little cartridge fuses inside the plug. They look like tiny glass cylinders with internal metal filaments like a lightbulb. Pop open the fuse cover and replace the fuses with those of identical size and rating.

Step 4: Check the Bulbs

This is probably the most time-consuming step. Depending on the lights, you might not know where the outage actually begins. Some lights have a single circuit, so the whole strand goes out if a single bulb isn’t working. Others have multiple strands, so only half your lights go out. To check the bulbs, follow these steps:

  • Identify the affected area, which will either be the whole strand or part of the strand, depending on the kind of lights you have.
  • Start at the problem area and inspect each bulb. You’re looking for any bulb that is loose in its socket, darker than the others, or has an apparent break in the filament or casing. 
  • Tighten or replace problem bulbs. Make sure all the bulbs are tight, so you don’t have to go over the strand again!
  • Test each individual bulb. If the previous steps didn’t help, it’s time to test each bulb separately. (Sorry. It’s the worst.) Take out each bulb from the problem area and place it in a bowl. While you have all the bulbs out, check the sockets for corrosion or debris you can clear out. Plug in the strand and insert each bulb, one by one, back into a socket. If it lights up, take it out, and place it in a separate bowl to use when you’re done testing the others. If it doesn’t light up, throw it away and replace it with a brand-new bulb. Or? Purchase a light tester.

Step 5: Make an Upgrade

If you need to get some new lights, we recommend upgrading. LED Christmas tree lights are more durable and efficient, and they often come in cool colors or with fun features. 

Step 6: Give Us a Call!

Sometimes trying to fix your Christmas lights means discovering more problems with your home’s wiring. If you notice issues with your circuit breaker or outlets during this whole process, take a deep breath and call us. We bring cheer to our DFW electrician customers all year round. Give us a call today!

TopTech Electric & Plumbing, Allen electrician, Corinth electrician, electrician near me, Farmers Branch electrician, Grapevine electrician, Roanoke electrician, Trophy Club electrician, Carrollton electrician, Cedar Hill electrician, Coppell electrician, Bedford electrician


TopTech Electric & Plumbing employs some of the best licensed electricians in Dallas and Fort Worth. We base this on their years of experience, the level of training they have undertaken, and the broad range of services they can provide. When you work with one of our electricians, rest assured that you’re working with a Dallas electrical contractor that has been thoroughly vetted for your safety and protection. All of our technicians undergo extensive background checks before they put on the TopTech uniform. We’re confident when we say that we hire the best. From ceiling fan installation to installing electric vehicle chargers, TopTech does it all!