How to fix a Galaxy S9 with fingerprint scanner not working, keeps saying to wipe fingerprint scanner

Here’s another instance of a developing issue with some #GalaxyS9 devices. If you’re having a problem with your phone’s fingerprint scanner, or if it’s not working at all, make sure to let us know so we can document them and update this post as well. The more cases we document, the better the chance that Samsung will notice.

Today’s problem: Galaxy S9 fingerprint scanner not working, keeps saying to wipe fingerprint scanner

Hello. I’m here to ask about this issue that I keep getting on my phone. It’s an S9, i got it a few months ago, and recently it keeps vibrating when I try to unlock it using the fingerprint scanner meaning it doesn’t recognize the fingerprint. So I decided to delete my previous fingerprints and add new ones, but as soon as I tried to do that it kept telling me to “wipe my fingerprint scanner.” So I did but the same kept happening. I even went and washed my hands thinking that my hands were dirty but it still happened… Hope someone can help me.  

Solution: Try resetting your phone’s settings and see what happens. Refer to the steps above.

Should a software settings won’t help, back your data up and factory reset the device. This should clear whatever software bug may be causing the problem.

We assume of course that your S9 was never physically damaged before this issue started occurring. If it was dropped or exposed to water before, you can assume hardware malfunction is behind the trouble. In that case, skip factory reset and contact Samsung instead.

For reference, these are the steps on how to do the suggested solutions.

How to reset your phone’s settings:

1. From the Home screen, swipe up on an empty spot to open the Apps tray.
2. Tap General Management > Reset settings.
3. Tap Reset settings.
4. If you have set up a PIN, enter it.
5. Tap Reset settings. Once complete a confirmation window will appear.

How to factory reset your S9:

1. Create a backup of your data.
2. Turn off the device.
3. Press and hold the Volume Up key and the Bixby key, then press and hold the Power key.
4. When the green Android logo displays, release all keys (‘Installing system update’ will show for about 30 – 60 seconds before showing the Android system recovery menu options).
5. Press the Volume down key several times to highlight ‘wipe data / factory reset’.
6. Press Power button to select.
7. Press the Volume down key until ‘Yes — delete all user data’ is highlighted.
8. Press Power button to select and start the master reset.
9. When the master reset is complete, ‘Reboot system now’ is highlighted.
10. Press the Power key to restart the device.

Other possible solutions

Some other users were able to fix fingerprint issues by addressing other possible angles like corrupted system cache or bad third party app. Make sure that you also wipe the cache partition and observe your phone while it’s on safe mode. Below are the steps on how to do these possible solutions:
How to wipe the cache partition:

1. Turn off the device.
2. Press and hold the Volume Up key and the Bixby key, then press and hold the Power key.
3. When the Android logo displays, release all three keys.
4. An ‘Installing system update’ message will show for 30 – 60 seconds before the Android system recovery menu options appear.
5. Press the Volume down key several times to highlight wipe cache partition.
6. Press Power key to select.
7. Press the Volume down key to highlight yes, them and press the Power key to select.
8. When the wipe cache partition is complete, Reboot system now is highlighted.
9. Press the Power key to restart the device.

How to boot to safe mode and check for possible bad third party app:

1. Turn the device off.
2. Press and hold the Power key past the model name screen.
3. When “SAMSUNG” appears on the screen, release the Power key.
4. Immediately after releasing the Power key, press and hold the Volume down key.
5. Continue to hold the Volume down key until the device finishes restarting.
6. Safe mode will display in the bottom left corner of the screen.
7. Release the Volume down key when you see Safe Mode.
8. Check for the problem.

If fingerprint scan works on safe mode but not normal mode, that means one of your third party apps is to blame. To identify which of your apps is causing the trouble, you should boot the phone back to safe mode and follow these steps:

1. Boot to safe mode.
2. Check for the problem.
3. Once you’ve confirmed that a third party app is to blame, you can start uninstalling apps individually. We suggest that you begin with the most recent ones you added.
4. After you uninstall an app, restart the phone to normal mode and check for the problem.
5. If your S9 is still problematic, repeat steps 1-4.

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