How to Test Laptop Charger with A Multimeter?

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Is your laptop charger not working after you plug it in? The problem is more typical than you assume it is. 

Your laptop’s charger is the oxygen supplier of your device. Without it, you wouldn’t be able to carry on with your routine activities. However, some carelessness and mishaps could often lead to the charger or the laptop’s charging abilities malfunctioning. 

If that’s the case and you find your laptop charger not working at all, this article will help you discuss the best possible solution. 

Common Reasons for a Faulty or Malfunctioning Laptop Charger

Every time you connect your laptop charger, you will immediately get a sign in the form of a beeping sound, or a dedicated LED built inside the computer lighting up. What if it doesn’t happen and you find your laptop not charging even after plugging it in? 

You may find a few reasons behind that concerns that include:

  • A problem with the power inlet of your computer
  • The battery and charger are old
  • The battery’s driver is outdated
  • A faulty adapter cable could not be delivering enough power to your laptop

Importance of Testing Your Laptop Charger

Understanding how to test your laptop charger can be practical for making sure your device is refilling batteries to a functioning level. The process for testing a laptop charger is very much the same irrespective of the charger you are working with. 

Keep in mind that not all laptop chargers put out the same quantity of current. The adapter in your car possibly charges your laptop a lot slower than the one plugged in at your table. Further, it may be a bit slower still if you utilize wireless charging. 

Even thinking of the variance in listed amperage among your chargers, others still degrade with time and take longer to finish a charge. That can be because of a worn or faulty cable or even a bad AC adapter. However, finding the root cause of such problems involves a huge amount of guesswork and is normally complicated.

Lucky for you, a multimeter can help you in this process. 

What is a Multimeter?

A multimeter, also referred to as a volt-ohm meter, is a handheld device utilized to calculate electrical voltage, resistance, current amperage, and other values. These devices come along in digital and analog versions and are helpful for everything from basic tests such as detecting faults, measuring battery voltage, and complicated diagnostics. 

They are one of the tools commonly utilized by electricians for troubleshooting electrical issues on wiring systems, power supplies, circuits, appliances, and motors. 

Take note that the power supply on your computer converts the alternating current from the wall outlet into a direct current flow, which the laptop’s components can utilize. Testing the DC voltage output of the power supply with a digital multimeter can help you prevent any concerns and identify if you have a bad power supply. 

You can always use probes to touch terminals and wires. You should not try using your own fingers. If you cannot hold the terminals or wires through the probes, you can also use a binder clip or a stand to secure them, so you don’t need to hold them through your hand. 

How Can You Use a Multimeter to Test Your Laptop Charger?

Are you wondering how you can test the functionality of your laptop charger using a multimeter? This section has the steps you need to follow.  

But commonly, the pin inside your charging connector is either damaged or curved. That could be a cause of charging problems. If you find the pin is curved, then straighten it with the use of a small screwdriver. Then plug your charger into your laptop. 

In case your laptop is still not charging, here’s what you need to do. Testing your laptop charger with a multimeter does not pose any risks, but you may electrocute yourself, your family members, or other people. 

If you’re not confident in doing this, please consult a professional electrician to do the testing for you. You can always get one. 

In this process, we will utilize a digital multimeter to test your laptop charger. So, get yourself a digital multimeter with an auto-ranging function. 

Your laptop charger has two parts: the main plug that plugs from the main socket and two pins. The other part is the adapter with the end plug going into your laptop. 

  1. Now, check the voltage on the adapter. Let’s use a 19-volt adapter in this scenario, but yours may differ. It takes 240 volts from the main socket as AC (alternating current) and converts it into a more sensible DC (direct current) of 19 volts into your laptop. 
  1. To test your adapter, ensure it is 100% plugged into the socket and switch on. Then plug the pin. 
  1. Make sure your leads are plugged into the right place. The black lead goes into the COM port, and the red lead goes into the VΩHz symbols. If you are in doubt, feel free to consult your manual. 
  1. Now, get your probes; the black is negative while the red is positive. Again, make sure your laptop charger is plugged into the main socket. Then switch on your multimeter and turn the tab to the DC signal.
  1. Get your adapter pin and carefully insert the red positive conductor inside, making sure it touches the tip. For the next step, grab your black negative probe. Place it on the tip of the outside of the edge.
  1. As you can see on your multimeter, you will have a reading of the volts of your laptop charger; and that’s how you test your laptop charger using a multimeter. 

Keep in mind that the voltage readings on your multimeter will vary on the output voltage specified by your laptop charger. Therefore, check the voltage values first on your AC adapter and compare them with the multimeter readings mentioned above. 

There you have it! We hope we’ve provided you useful information you can use to test your laptop charger. With proper equipment and knowledge, you can do this task as efficiently and effectively as possible. 

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