If your Huawei Pura 70 Pro's fingerprint scanner is acting up, you can't unlock your phone or access secure apps. It's a common hiccup, but usually one you can fix yourself without too much trouble.
Clean the Under-Display Sensor
Start with the simplest fix. The optical sensor under your screen needs a clean surface to see your fingerprint clearly. Wipe the entire lower portion of the screen with a soft, dry microfiber cloth.
Pay special attention to the area where the fingerprint icon appears. Any smudges, grease, or moisture from your hands can block the sensor's view and cause it to fail.
Restart Your Pura 70 Pro
A quick restart clears out temporary software glitches that might be confusing the sensor. Just press and hold the power button for about ten seconds until you see the Huawei logo appear and the phone reboots.
This is different from a normal shutdown and power-on. It forces a fresh start for all the system processes, including the one that handles biometrics.
Check Your Finger and Technique
Make sure your finger is clean and dry. Even a little sweat or lotion can create a blurry image for the sensor. Also, press down firmly and hold your finger in place for a full second.
Don't just tap it. The optical sensor needs a moment to capture a good image. Try using a different finger that you've also registered to see if the problem is with one specific print.
Re-register Your Fingerprint
If the scanner is inconsistent, the saved print data might have gotten corrupted. The fastest fix is to delete the old one and add it again. Go to Settings > Biometrics & security > Fingerprint ID.
Enter your lock screen password, tap the fingerprint giving you trouble, and select Delete. Then, tap New fingerprint and follow the prompts, making sure to rotate your finger to capture the edges during enrollment.
Update Your EMUI Software
Outdated system software can have bugs that affect hardware like the fingerprint sensor. Huawei releases updates to patch these kinds of issues. Open Settings and go to System & updates > Software update.
Tap Check for updates and install any available updates. I've seen minor updates specifically address biometric authentication problems on other EMUI versions, so this is always worth a shot.
Inspect Your Screen Protector
This is a big one for under-display sensors. A thick, low-quality, or poorly aligned screen protector can block or distort the sensor's light. If you recently applied a new protector and the scanner stopped working, that's likely the cause.
Try carefully removing the protector temporarily to test the scanner. If it works perfectly without it, you'll need a protector marketed as compatible with under-display fingerprint sensors.
Disable Battery Optimization for Security Apps
EMUI's aggressive battery management can sometimes put security services to sleep, which might interfere with the fingerprint process. Go to Settings > Battery > App launch.
Find any system apps related to security or biometrics. Tap on them and make sure Manage automatically is turned off, then check Allow background activity. This ensures the fingerprint service is always ready.
Boot into Safe Mode
This checks if a third-party app you installed is causing a conflict. Press and hold the power button until the power off menu appears. Then, press and hold the "Power off" text on screen until you see a prompt to reboot to Safe Mode.
Tap OK. In Safe Mode, test the fingerprint scanner. If it works perfectly here, a recently downloaded app from the AppGallery or another source is the culprit. You'll need to uninstall apps one by one to find the offender.
Clear the System Cache Partition
Corrupted temporary system files can lead to all sorts of glitches. To clear them, first power your phone off completely. With the phone off, press and hold the Volume Up button and the Power button together.
Release them when the EMUI recovery screen appears. Use the volume buttons to navigate to Wipe cache partition and select it with the power button. Confirm, then select Reboot once it's done.
Check for Physical Damage
Look closely at the screen in the fingerprint area. Even a small, shallow crack or deep scratch directly over the sensor module can disrupt its function. Also, ensure the screen isn't lifting away from the frame at the edges, which could indicate a loose connection inside.
If you suspect physical damage or if the sensor area feels significantly hotter than the rest of the phone, the hardware itself may be faulty. In that case, contacting Huawei support or a repair professional would be the next step.
