Tech Issues 01: Fingerprint Scanner

Top 7 ways to fix faulty fingerprint scanners.

by Joy Festus
4mins read

Fingerprint scanners on smartphones have over-time evolved from capacitive scanners to in-display. It gives a sense of security and we can get annoyed when it starts malfunctioning. This article will address various reasons why your mobile phone fingerprint scanner malfunctions and ways to correct it on your smartphone, whether it is side-mounted, rear- mounted or in-displayed. Here is what to do.



Fingerprint scanners can not read fingers if the surface is dirty or wet. The recognition system accuracy is easily affected by skin conditions of the owner and will fail to function as capacitive scanners use a grid of small capacitors which discharge at the point where the fingerprint touches. You can make use of cotton swab to clean all kinds of oil stains or microfibre materials damped in iso propyl to clean in-display fingerprint sensors. Ensure your finger is wiped clean before placing it.


Sometimes, the sensor fails to function unless you unregister and re-register your fingerprints. To do just that, try this step.

Go to your settings >> Click on biometrics and security. Then tap the fingerprints option >> enter your pin >> tap registered fingerprint >> click delete>> then add fingerprint option to re-register.


Slow response to fingerprints can be caused by low touch sensitivity. The good news is you can increase this on your device.

However, this method is not available on Android yet but for in-display scanners on Google Pixel, iPhone and the likes. Follow the steps below.

Go to the settings app >> click the display section >> tap touch sensitivity action >> then enable the toggle.


You can get irritated by constant update notifications, differ for a long time and sometimes ignore them. Well, not regularly updating the available versions of your software can be one of the factors causing a faulty sensor. Updating it helps to check bugs on your device.


If you are locked out of a device whose fingerprint scanner is not working well, any of these methods can be used to clear excess data stored and free of space for proper functioning of the biometric scanner.

Wipe system cache method: this helps resolve the issue by affecting the memory that sometimes clogs and results in malfunctioning fingerprint sensors. To use this method, you have to switch off the device >> restart it >> while on recovery mode >> wipe cache partition using the volume buttons >> confirm the action with the power button >> and finally restart it.

Factory reset option: before using this option, do a complete backup of your smartphone.  Click the reset option >> enter your pin or password and then it will be as good as new.

You can also download the iToolab Unlock Go (Android) app. It works for androids, Samsung, Xiaomi, Huawei etc.


How do you fix scanners whose fingerprint sensors are not working and you cannot re-register or unregister old ones? This is where your service center comes in.  No quick DIY method or local phone repairman can help except if you visit the service center. For TECHNO, Itel and Infinix phones, kindly take them to the Carlcare service center closest to you. Carlcare is the official service provider for the aforementioned Android devices. For other types of smartphones, you can check your device operator for more information.


This is not advisable for newbies. Do not try it, but if you are an experienced tech individual who can replace sensors by yourselves and want to prevent paying a high fee, you can check out audio and videos online but with great caution. e.g iFixit for online repair.


DIY that can help resolve non-complex issues.

Restart: most simple issues can be fixed by rebooting the device because phones that have not been restarted for a while tend to lose their efficiency.

Add the same fingerprint twice or more for accuracy and speed.

Remove screen protectors of in-display fingerprint scanners, that is, optical and ultrasound types of scanners. If the screen protector is too thick, it can reduce the functioning of the biometric scanner.


Related Posts

Leave a Comment