How to Check Mobile Components with a Digital Multimeter

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Your mobile phone has many different parts inside. If one of those components is not working properly, it can destroy your entire experience. However, how do you determine exactly what’s wrong with your mobile device? 

Perhaps the accelerator seems strange, or web browsing on your Wi-Fi or mobile data feels sluggish. How about if you purchase a secondhand phone and would like to check if everything works perfectly?

Whatever the concern, there is a device that can help you determine what is wrong with your mobile phone. Even if you don’t have a certain issue, running a mobile phone test to ensure everything is ticking along perfectly is a good idea. 

In today’s post, we will cover how to check different mobile components with a digital multimeter. 

What is a Multimeter? 

A multimeter is a convenient and multifunctional tool accessible to many households. They could measure different things, including mobile components. 

You will find different types of multimeters. Two of the most popular and widely utilized are analog multimeter and digital multimeter. 

The latter uses a digital display on the LCD screen to present values. Meanwhile, the analog versions use a needle-like pin that moves from left to right while giving readings over a series of values. 

Most mobile phone technicians prefer to use digital multimeters as it seems to be a better option and simpler to use. 

Phone’s Battery

Batteries are small containers of chemical energy. When a mobile phone is connected to the mains, current is utilized to reset a chemical reaction in the battery, sending electrons from the negative anode to the cathode—the battery’s positive end.

After charging, the battery could then produce electricity by driving electrons through a circuit. 

In that case, a phone, to the anode and will continue doing so until all the electrons contained in the battery have moved to the anode. 

  1. Keep your multimeter in the DC voltage mode (20 volts)
  2. Check if the voltage is reflecting between 3.7V to 4.2V. 
  3. The battery needs to be boosted or to be changed if the voltage is less than 3.7 volts. 


In case you didn’t know yet, a ringer is a kind of card-level component of a smartphone that plays or rings a loud sound. It is also known as Melody, Loudspeaker, Buzzer, IHF Speaker, and so much more. Today, there are many different ringers in the market with different shapes and sizes based on different smartphone models. 

You will find different types of issues in a smartphone’s ringer, such as the ringer produces less sound, loudspeaker not working, the sound is not clear, phone not ringing, and many more. 

To check if your mobile phone’s ringer is working or not using a digital multimeter, here’s what you need to do:

  1. Keep your multimeter on the buzzer mode and check the ringer.
  2. The value should be between eight to ten ohms. 
  3. The ringer is in good condition and doesn’t need any replacement if the value is between that range. 
  4. The ringer should be replaced if the value on the digital multimeter is other than the value mentioned above. 

Battery Connector

A battery connector is a device connecting electric circuits. Many battery packs need more than a single connector. The main battery connector is both an electrical and mechanical part, which interfaces the battery to the PDA or other electrical device. 

Here’s what you need to do to check this mobile phone component:

  1. Keep your digital multimeter on 20V DC and check for the voltage that must appear between 2.5 Volts to 4.2 Volts.
  2. There should be an issue with the charging section if the voltage does not reach that range. 


Microphones or mics were initially invented together with telephones. Most types of microphones have been created since then. 

These days, a lot of individuals bring a mobile phone and hence a microphone along with them. Are you wondering what type of microphones are used in your mobile devices?

Cellphones utilize small electric condensers, also known as MEMS microphones. Those mics need very minimal power to work that is then effortlessly delivered by the mobile phone’s battery. These mics also fit perfectly inside the typical mobile phone’s circuitry. 

To check your mobile phone’s microphone with a digital multimeter:

  1. Keep your digital multimeter on the Buzzer Mode
  2. The value on your device must appear in the range between 600 to 1,800 ohms. 
  3. Remember that your multimeter will also give a beep sound.
  4. If it is not within the range, your microphone is faulty and needs to be replaced. 
  5. Take note that only one side of the probe will present value. Your digital multimeter won’t give any value if the test lead or probe is connected in reverse. 


A vibrator is a card-level part of a smartphone that vibrates. It is also referred to as a motor and is controlled by Power IC or Logic IC. 

When you receive a call, the motor begins to function and quickly unwinds the cylinder. Vibrations are communicated to the mobile phone’s case and then begin to vibrate. 

To test whether your mobile phone’s vibrator is working or not using a multimeter, you need to:

  • Keep your digital multimeter in Buzzer Mode.
  • The value should be between 8 Ohms to 16 Ohms. 
  • If the value is not between that range, then you need to change the motor or vibrator. 


A speaker is a tiny sound driver fitted inside your mobile device and is utilized to create sound. These small devices have a metal coil known as an electromagnet which produces a magnetic field when an electric current flows through it. 

To test if your mobile phone speaker is working or not, follow these steps:

  1. Keep your digital multimeter on Buzzer Mode.
  2. The value of the speaker must give in the range of 25 Ohms to 35 Ohms
  3. If you reach that range, it means the speaker is perfectly working and doesn’t need to be replaced.
  4. If you didn’t reach that range, it’s a clear sign you need to change it. 

Final Thoughts

There you have it! Above are some common mobile phone components and the proper ways of testing them with a multimeter. If you believe some of these parts are causing your phone to malfunction, consider testing them right away.

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