[GUIDE] Fix PERSIST.IMG Loss Of Finger Print Sensor

risay07

Senior Member
Oct 12, 2011
127
13
0
Penang
Hi @antnyhills, my OP6T encounters the same error. Since the issue was caused by corrupted persist partition, do you think flashing persist partition extracted from Stock Fastboot rom via fastboot would fix it?

Edit: I have proceeded according to the instruction. The finger print calibration test fail early for me. It says:
SPI
PASS!
PASS: FLASH ID: (7 numbers),SENSOR ID: (4 numbers),MCU ID:2,PMIC ID: (4 numbers)

MT_CHECK
FAIL!
FAIL:GF_SZ_FT_ERROR_CHECK_MT_FAIL


Anyone knows what MT_CHECK means and why it fails?
 
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totmakina

Senior Member
Nov 13, 2013
150
59
48
Hello :
I lost my fingerptomy of unbrick the oneplus 8 from MSM 10.5.9. When closing the boot I lost the track.
What I did to try to fix it was:
- Re-flash with MSM 10.5.8
-When starting the mobile I skipped all the configuration
-Go directly to developer options and activate OEM unlock and USB debugging.
. Connect the mobile to the PC and put the mobile in fastboot mode.
. Unlock by fastboot and reboot
- Agira at this time YES, start configuring the mobile including the fingerprint.
- After updating via OTA the oneplus until 10.5.12

In this way I was able to solve the loss of fingerprint

In this way I was able to solve the loss of footprint
Hope this can be of use to someone.
Thank you
 

VinDw

New member
Sep 23, 2020
1
0
0
How to get root access to copy persist.img file

New video guide below

VIDEO GUIDE


1. *VERY IMPORTANT* We need to back up your broken persist.img and store it in a safe place. PC preferred. We will need this later. Do not leave the backup on the device as the next step will wipe the device.

*IF YOU LOOSE THIS PERSIST.IMG BEFORE WE MODIFY IT WITH A CALIBRATION, YOU LOOSE ALL CHANCE OF FIXING THIS YOURSELF*

*IT HOLDS IMPORTANT FP CALIBRATION DATA THAT WE WILL BE OVERWRIGHTING IN THE NEXT FEW STEPS*

Note: This requires root​

Type this into terminal or ADB shell with root privileges.
Code:
dd if=/dev/block/bootdevice/by-name/persist of=/sdcard/persist.img
Backup the partition to another device. Preferably a PC as you may need one in the later steps.

2. Next we have to restore our OS to an earlier OOS. (10.5.4 is what I used and recomended)

Use the MSMTool to restore your device to 10.5.4.​
Note: You will loose your unlocked bootloader and will be required to unlock your bootloader once more.​

Guide and Source for MSMTool
MSMTool 10.5.4 Download

3. Next step is to unlock the built in 'Factory Mode' I have a guide on how to do this below.

[GUIDE] Unlock Factory Mode *root*

4. Now we need to perform a FP calibration. We want to fail.

  • Enter Factory Mode as shown in the previous guide. (*#801# in the stock dialer)
  • Swipe over to "Device Debugging"
  • Select "Finger print test"
  • Select "Finger print calibration test(Pure White - 90% Blue)
  • Select "Start Test"
  • Keep on going through the tests (You must hold an object or your finger over sensor on all BUT THE BLACK RUBBER TEST of these test for it to work!)
  • The test will fail and this is what we want. There should be a lot of red lines, if you only have one or two try again.

5. We need to extract the the old broken persist.img
NOTE: It is important that we extract the backed up persist.img as it has been unmodified by our recent calibration. This persist.img although broken still has all our working calibrations on it including Finger Print calibrations.

The way I did this is by opening it extracting it via 7-ZIP on my PC​

Once extracted move the 'DATA' folder and the 'ENGINEERMODE' folder to the root of your sdcard.​


6. Download a root explorer. I highly recommend 'Solid Explorer' from the Play Store.

  • Open 'DATA' folder and delete 'gf_persist.so'
  • Select the 'DATA' and 'ENGINEERMODE' folders you just put on the device and place them at /mnt/vendor/persist/
  • It should ask you if you want to keep the old or new files. Select to keep the new.
  • Reboot.

7. If you followed all my steps correctly this you should be able to go into settings and add your fingerprints.


Why does this work?

Good question... I think what is happening is something in the persist partition breaks which causes the device to think that the sensor is not calibrated when in fact it still is.
When we start and fail a new calibration this fixes whatever was broken in our partition. But now we have a failed calibration.
So what we do is take the files from our backed up persist partition and move over all the necessary files that have our original calibration. But now our partition has the part of it that wasn't working fixed.

I spent a good many days working on this fix (1-2 hundred hours or so). I hope you can be respectful if you have issues. Please kindly ask below and I'll do my best to help.
Hi there,

I'm using a OnePlus 8 (IN2010) and my fingerprint stopped working around a week ago. I'm new to this stuff & would really appreciate if someone could link me to a working method to root my device as this tutorial states that root it required.

Also, will using a OOS downgrade package do any alterations to my persist.img file?


Many thanks!
 
Nov 13, 2015
35
8
0
I followed the guide and got to the factory mode.
When I try to start the finger print calibration test, I get the following error: "The application cannot reach the android service for the sensor."
I am using the OP8 Indian Version.
Help!!!!
Edit: Fixed it by skipping the calibration test and restoring the FP data and then updating to the latest stable.
Hey man, I got the same error as you, did you fix by just copying the data from your old persist.img again?
 

beany23

Senior Member
Jan 15, 2015
628
484
83
I tried this over and over again and I still can't get it to work. I'm now on a11 and feel I'll never have my fingerprint back again.
 

starcms

Senior Member
May 7, 2010
901
400
83
New Orleans
Something interesting happened today, I decided to install Android 11 developer preview 4 and I decided not to root but I noticed my fingerprint scanner is working without being rooted which is strange I wonder if somehow I could go back to 10.5.20 and get fingerprint working again without root?
Root or no root has no effect on it working. If you relock the bootloader (manually or by running the MSM tool), and had applied the fix in this thread, you'll lose FP again. I'm assuming this is because the phone checks persist at that time and the checksum doesn't match the expected one so it corrupts the FP data again.

If you used this fix:
A) FP will work only with an unlocked bootloader.
B) Relocking the bootloader breaks FP again (it can be unlocked and fixed again. Very very easy if you made a backup of your fixed persist partition which I highly, highly recommend)

So it's impossible to have both FP working and a locked bootloader if you used this fix.
 
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starcms

Senior Member
May 7, 2010
901
400
83
New Orleans
Is there no permanent way to fix it? & Does it effect everyone who rebranded OnePlus 8?
The only way to permanently fix it (meaning FP sensor working with bootloader locked) is to run the MSM tool and then RMA to OnePlus asking for fingerprint recalibration. Or RMA it with a picture showing the FP error message. Believe it or not, this has occured to people who never unlocked their bootloader. And never modded their phone one bit.

If you back up your persist.img immediately when you first get the phone back before even unlocking the bootloader, you can easily restore it if/when it gets corrupted again. And not have this issue. I'd recommend backing it up even if you don't plan to unlock the bootloader again because it has happened to people that never did...

Rebranding didn't cause it. Unlocking the bootloader combined with dozens of possible different things most likely caused it.

The whole issue is due completely to OnePlus's incompetence, A10 and the new dynamic file system, OnePlus not fully understanding how it works, and putting persist in an "open" area of the phone. Instead of locking it down and making it virtually impossible to corrupt. As I said, it can even become corrupt even if the bootloader has never been unlocked...
 
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Saeem

Senior Member
Jul 31, 2015
481
108
73
22
Ad Dammam
www.nurullahsaeem.com
The only way to permanently fix it (meaning FP sensor working with bootloader locked) is to run the MSM tool and then RMA to OnePlus asking for fingerprint recalibration. Or RMA it with a picture showing the FP error message. Believe it or not, this has occured to people who never unlocked their bootloader. And never modded their phone one bit.

If you back up your persist.img immediately when you first get the phone back before even unlocking the bootloader, you can easily restore it if/when it gets corrupted again. And not have this issue. I'd recommend backing it up even if you don't plan to unlock the bootloader again because it has happened to people that never did...

Rebranding didn't cause it. Unlocking the bootloader combined with dozens of possible different things most likely caused it.

The whole issue is due completely to OnePlus's incompetence, A10 and the new dynamic file system, OnePlus not fully understanding how it works, and putting persist in an "open" area of the phone. Instead of locking it down and making it virtually impossible to corrupt. As I said, it can even become corrupt even if the bootloader has never been unlocked...
I'm having a chinese OnePlus 8 & there no way I'll be able to claim the warranty without sending it to China unless it has international warranty, which it probably doesn't have. I tried looking for authorized service centers of OnePlus & even contacted Amazon who is an authorized seller of OnePlus in UAE, they said they won't be able to do a thing in Saudi Arabia even if I have bought this device from them as I do not have the Order ID, they do not know anything about IMEI like other sellers. ?
I'm good with unlocked bootloader but I hate the fact that Fortnite has some super power to detect unlocked bootloader even with magisk hide & everything, 90fps just doesn't work & the graphics quality is poor.
Can a system update from OnePlus fix this problem or does OnePlus have any way to fix it remotely?
 

Vomitblood

Member
Jan 25, 2020
11
2
3
Request for persist.img for OnePlus 7T Pro

Hi there, my OnePlus 7T sensors are not working.
I have found a persist.img for OnePlus 7T Pro and flashed it.
That solved the problems for all the sensors EXCEPT for this fingerprint sensor.
The persist.img's data folder only has 8 files, and it does not contain 'gf_persist.so'.
I suspect that it is not a complete persist.img, although it seems to have fixed all the other sensor problems.
May I request for another persist.img file?
Thanks.
 

starcms

Senior Member
May 7, 2010
901
400
83
New Orleans
Hi there, my OnePlus 7T sensors are not working.
I have found a persist.img for OnePlus 7T Pro and flashed it.
That solved the problems for all the sensors EXCEPT for this fingerprint sensor.
The persist.img's data folder only has 8 files, and it does not contain 'gf_persist.so'.
I suspect that it is not a complete persist.img, although it seems to have fixed all the other sensor problems.
May I request for another persist.img file?
Thanks.
You need the persist.img from your actual phone if you have any hope of fixing FP without RMA. So, your only option at this point is RMA.
 

starcms

Senior Member
May 7, 2010
901
400
83
New Orleans
I'm having a chinese OnePlus 8 & there no way I'll be able to claim the warranty without sending it to China unless it has international warranty, which it probably doesn't have. I tried looking for authorized service centers of OnePlus & even contacted Amazon who is an authorized seller of OnePlus in UAE, they said they won't be able to do a thing in Saudi Arabia even if I have bought this device from them as I do not have the Order ID, they do not know anything about IMEI like other sellers. ?
I'm good with unlocked bootloader but I hate the fact that Fortnite has some super power to detect unlocked bootloader even with magisk hide & everything, 90fps just doesn't work & the graphics quality is poor.
Can a system update from OnePlus fix this problem or does OnePlus have any way to fix it remotely?
No...and fortnite runs fine here using MagiskHide...
 

Saeem

Senior Member
Jul 31, 2015
481
108
73
22
Ad Dammam
www.nurullahsaeem.com
No...and fortnite runs fine here using MagiskHide...
Can you tell me how you managed to do it?
I did some digging & found a lot of people are having this problem of fortnite not running properly on their unlocked device. I used to get kicked out of the game, which i manage to fix using magisk hide & disabling developer mode. Sadly now my graphics is terrible (3D games of 2005 are better) & I cannot exceed 60fps even when i set 90fps to be the default. ?
 

succumbtothegreater

Senior Member
Jun 15, 2013
520
236
63
Thank you so much for this guide!!! I broke my screen and replaced the screen/frame myself and when I booted up, I had no use of the fingerprint scanner. It said "Fingerprint Hardware Not Available". After following this guide, I'm able to use it again!
 

PP1723

New member
Dec 3, 2017
2
0
1
Same problem for me. if Bootloader is unlocked the FP is working fine, but if I relock the bootloader I got the FP enrollment error. What's wrong with Oneplus? Do you think they manage to fix this problem? Otherwise I think I will sell my phone and switch to Xiaomi