Fingerprint scanner not responding? Step-by-step instructions on how to fix everything

Security methods are key in the daily use of smartphones, among them the fingerprint sensor is the most popular as it provides us with a fast and very reliable average. This is, however, not without some problems that we encountered when unlocking Samsung phones with both an on-screen and rear-mounted fingerprint scanner.

These problems span all price ranges, making them common problems that we can solve with the same user interface and with different tips. Before going directly to our fingerprint reader problem, we recommend that you use alternative vibrations in other tasks because this may be the case where we personally work for us.

Contents [show]

• Fingerprint sensor does not respond on Samsung Safe Mode solves the problem
• Dry your mobile completely

The fingerprint scanner is dirty: dirt is a common cause

If the fingerprint scanner stops working, there may be several reasons for this. Illustration: Pixabay

As soon as your hands become dirty, you wash your hands - but the smartphone, however, is not cleaned as often. Dirt is probably the most common reason for a fingerprint scanner to stop working. The following tips will help you clean up:

1. First, use a piece of adhesive tape (such as regular tape) to remove any coarse dirt from the fingerprint scanner. Stick a piece and press it onto the entire surface of the scanner. After this, carefully peel off the tape.
2. Take a piece of cooking paper and moisten it with a few drops of clean water. Wipe the fingerprint scanner thoroughly with it.
3. If, despite the above steps, you still see contamination, use a few drops of disinfectant (that's what alcohol is called at the pharmacy) on a microfiber cloth or kitchen paper and wipe the scanner with it. After thorough wiping, even the most stubborn dirt stains should be removed.

4. After this, ensure that the scanner and your fingers are dry.
5. Try using the device again. If the fingerprint scanner continues to fail even after thorough cleaning, there may be another reason.

Why doesn't the fingerprint sensor work?

There are many reasons why a sensor can fail. The most common ones include the following:

• Damage to the button sensor cable when you open the device yourself or after severe mechanical damage.
• A glitch in the smartphone software.
• The scanner surface is heavily soiled.
• Changes in the fingerprint pattern when the skin is damaged, its hardening.
• A protective film or glass that prevents your finger from touching the screen.

Moreover, the user does not always have an urgent need to take the phone to a service center. I’ll say more, most often it’s enough to carry out a few simple manipulations, and everything immediately falls into place.

Fingerprint is not recognized: recheck your fingers

The problem with the fingerprint scanner may also be your fingers. With cuts, burns, traces of chemicals and other damage to your fingers, you significantly complicate the fingerprint recognition process for the scanner. Check if there is something similar on your fingers.

1. Add a new fingerprint to the system, or use another finger that is already saved.
2. Already when setting up a new fingerprint, you will notice whether the scanner works or not. If it recognizes a touch and the finger is still scanned, then the module is functioning and the reason lies in a specific finger.

Delete and rescan fingerprints

There are often lesions on the fingertips that complicate the recognition process. It also dries out and becomes rough in the cold season. If the sensor does not work, it is logical to sometimes update the fingerprints in the settings. It will be convenient to scan several fingers, for example, the index and thumb of both hands.

Important! It is better to scan each finger twice from different angles. This will increase recognition accuracy.

It’s also worth adding a wet fingerprint - after washing your hands, you often have problems unlocking your smartphone.

Is your fingerprint scanner broken? Test your equipment

Using various applications you can check whether there is a hardware defect

Using various applications on your Android device, you can check whether your smartphone's hardware is still functioning.

1. Download the Test Your Android app from the Google Play Store.
2. Launch the application and select “Fingerprint Scanner” from the menu.
3. Place your finger on the scanner. If the finger pattern can be recognized, the app will confirm this. If you scan a finger that has not previously been saved in the system, a “not recognized” notification will appear. In both cases, this means that the scanner is still functioning.
4. If, after you place your finger on the scanner, the screen still displays the instruction “Place your finger on the scanner,” then most likely there is a hardware defect. In this case, your device must be rechecked and repaired by specialists.

Battery completely discharged

In some cases, the option of completely discharging the battery helps. We bring its value to 0% and wait until the mobile device turns off due to lack of charge. Then we connect it to the network, but the device itself should not turn on.

Once it reaches 100% charge, you need to turn on your Xiaomi smartphone, leaving it connected to the network. You will need to wait a little until the screen prompts you to use a fingerprint sensor for identification. After applying your finger, there is a high probability that the software failure will not recur.

Fingerprint scanner defect: how you can fix the software error

In some cases, a bug in the operating system may cause the fingerprint scanner to not function properly. You can try the following tips:

• Restart your device to clear any errors.
• Install the latest updates for your device.
• If you only recently installed updates, you can try to restore the old version. Or you can wait until the manufacturer releases the next update that can fix the problem.
• You can also try restoring the system to its factory state. However, be sure to back up your data before doing this, otherwise it will all be permanently deleted.

Check smartphone software updates

Incorrect operation is often associated with errors when updating the phone. You need to check the current version of system programs and those applications for which the sensor does not work correctly.

Important! If problems started after installing the latest version of the software, then you should look for previous stable versions and use them.

As a last resort, you can restore the device to factory settings. To do this, you need to make copies of important data, go to the smartphone settings and select the appropriate function.

How the scanner works

The scanner can be located in 3 places: on the back of the case, on the side near the power button or under the screen itself. The first 2 options are found in devices from the low and mid-price segment. Only flagship devices are equipped with under-screen scanners.

See also: MediaTek showed the mid-range chip Dimensity 800

Now let's see how the fingerprint sensor works. The lines on the fingers are called "papillary patterns". Minutes (these are sections of the pattern) are interrupted, bifurcated and merged in their own way for everyone. This is what makes the print so unique. The sensor remembers your papillary pattern, and the device is unlocked only if a finger with the same lines touches the sensor.

Fingerprint sensors can be divided into 3 types: optical, capacitive and ultrasonic.

1.Optical sensors are found in devices with AMOLED screens that implement under-screen technology. In fact, it is a camera that takes a photograph of the fingerprint and remembers it. Recognition occurs using light. The user needs to touch the display in a certain place and the lock will be removed. One of the disadvantages is that the optical sensor begins to work incorrectly if dust or moisture gets on the display.

2. A capacitive scanner contains conductive plates whose thickness is less than the papillary pattern. In such plates a capacitor with a current charge appears. And the papillary pattern is unique protrusions and depressions. The sensor uses voltage to recognize them and determine the fingerprint. Such scanners are placed on the case or near the power buttons.

3.Ultrasonic sensors. This technology was introduced by Samsung. This is the best scanner option that can provide security by creating 3D images. Moisture and dust do not affect fingerprint scanning.

Mechanical failure

First of all, the most standard and popular option stands out, which consists of damage to the cable during disassembly of the mobile device, and the problem can arise if the cover is abruptly removed without detaching the tape. In such situations, professional help is required.

Did the device hit a hard object or did water get inside the case? It is likely that the fingerprint scanner will subsequently stop functioning correctly. Also take a close look at the back of the smartphone. The presence of dirt or moisture on the surface of the scanner disrupts contact, so it is recommended to carefully wipe the smartphone with an ear swab soaked in alcohol, in particular for the fingerprint reading key. Likewise, the presence of small cuts on a finger will not allow the user to be identified correctly, and the hands themselves must be kept dry.

When and why iOS deletes fingerprint data from RAM

Perhaps the most interesting thing about iOS security is the question of under what circumstances iOS will delete fingerprint data from the device’s RAM and force the user to re-authorize using an unlock code. But first, let's think about why Apple even needed to periodically delete fingerprints?

The company understands very well (and understood three years ago) that any biometric system can be deceived. Yes, Apple has developed excellent fingerprint scanners, which are not as easy to bypass as a sensor on, for example, the Samsung Galaxy S5. But it’s still possible. After all, the owner can be forced to use their finger to unlock the phone - only under the American legal system, this requires a warrant, which takes time to obtain... after which the phone will erase the fingerprint data from its memory and will not allow the device to be unlocked with a fingerprint.

Sounds like a stretch? Smacks of a conspiracy theory? No, Apple just really didn’t like the attempt at pressure from law enforcement agencies, in response to which it introduced this measure: Apple adds another rule forcing iPhone and iPad users to employ a passcode to unlock their device.

But let’s not get distracted, but look carefully at the conditions under which the system blocks Touch ID and forces you to log in using a lock code. The Touch ID sensor is turned off and fingerprint data is cleared from the device memory when any of the following conditions are true:

• the phone is turned off or rebooted;
• the user adds the data of another finger;
• the phone receives a remote lock command via Find My iPhone;
• there were five unsuccessful attempts to unlock using a fingerprint in a row; • the device was never unlocked for two days;
• anti-policeman: more than six days have passed since the last time the lock code was entered, and the device itself has not been unlocked by the Touch ID sensor within the last eight hours.

The meaning of the last point needs to be clarified. According to the PhoneArena website, it “may complicate the work of law enforcement agencies.” I would put it more confidently, because the last point was introduced immediately after the sensational trial with the terrorist from San Bernardino, when unprecedented pressure was put on Apple.