Boot-loop/boot failure on Pixel 9

bchall

Hello GrapheneOS forums,

I have been a happy GrapheneOS user on my Pixel 9 for about 1.5 years now. My phone was updated to the latest stable release, 2026032000.

Yesterday, my phone began rebooting continuously. It was fully charged, so I don't think this is related to other issues I have seen where a dying battery results in an unclean shutdown (see this thread for example).

The behavior I see is:

The phone shows the "Booting another operating system" screen.
The screen shows the Google logo for a short time (about 10s).
The process repeats. I never see the GrapheneOS logo.

Following the suggestions in this other thread, I rebooted into GrapheneOS recovery and attempted to adb sideload the most recent release, which is the same version I am running.

I am not sure if it is notable, but when I view the system log in Recovery, I see the following warning in it:

[0.000335] W:[libfstab] Warning: device does not exist : /dev/block/by-name/zoned-device

Unfortunately, when I go to sideload the update, I get the following:

Finding update package...
Verifying update package...
Update package verification took 92.5 s (result 0).
Installing update... 
ERROR:   recovery: Update package is older than the current build, expected a build newer than timestamp 1773969441 but package has timestamp 1773969440 and downgrade not allowed.

Install from ADB completed with status 1.
Installation aborted.

I think the sideloading facility should allow reinstalling the current version, so I don't understand why installing the same version is treated as a downgrade.

Is my understanding correct that my options right now are to either wait for a newer GrapheneOS release to try and sideload, or to factory reset my device? I would prefer to not lose the data I have on it.

Any input would be appreciated.

Johnnyloans

bchall
Hello, you're almost home free!

The "version is 1 second too old" means your phone has "security preview updates" enabled.

The OTA version you download must be incremented by 1 in the URL. (Right click and copy the URL to edit).
Normal Version: 2026032000
Security preview: 2026032001

If you do have a pixel 9, not 9 pro/9a
Normal (wrong for you):
https://releases.grapheneos.org/tokay-ota_update-2026032000.zip
Security preview:
https://releases.grapheneos.org/tokay-ota_update-2026032001.zip

Try again with the bottom link.
Your phone could very well have a hardware issue causing random issues. Keep backups on 1 or 2 other devices. Messages, contacts, list of apps you have installed, the icon layout, call history if you need, photos, downloads, screenshots, calendar if local only, password or key info (e.g. vanadium), etc

Take care!

bchall

Johnnyloans

Thank you for this! I do remember enabling security preview updates now.

This time I was able to successfully install the update via adb sideload. Unfortunately the device still boot-loops. So there might be some other underlying issue. Is there anything else to try before factory reset?

Johnnyloans

bchall

Sorry it didn't fix your issue just yet.

After you flashed it, did you allow it to boot up twice? It might have switched over to the other boot slot after the first failure. Have it boot again if not.

Don't allow it to boot loop unnecessarily. If you have backups of all of your data, I'd factory reset. If not then read on.

There are 2 sets of data to boot from, slots A and B.

Maybe you know which one you flashed already then you can do the other one (you can't change the slot yourself if fastboot says bootloader is locked. If so, then only the phone can change the slot).
The fastboot screen shows which slot it's on near the bottom.

Record the slot letter. Flash it. Let it boot up twice. Then hopefully it is on the other slot to flash.

Boot up twice. If it still doesn't work, perhaps you have a warranty or within your return to the retailer period.

bchall

Johnnyloans

Thanks again for the additional help.

Yes, I did allow it to attempt to boot several times. The behavior is the same, showing only the Google 'G' and then restarting. No GrapheneOS splash screen.

For my first attempts, the boot slot was 'a'. I can't change the slot because the bootloader is locked, as you mentioned.

Subsequently, when I sideloaded the update, I rebooted back to the bootloader from the Recovery and saw that the slot had changed to 'b'. Even so, it fails to boot past the 'G' Google logo. After letting it attempt to boot >2 times, the slot has changed back to 'a'.

Johnnyloans

bchall

Wow, sorry man, that's defeating.

I've seen some people on the forum say they successfully warrantied a device with GOS still on it.

Psyonico

I don't remember how to activate it, but have you tried booting into safe mode?

bchall

Psyonico

Yes, I tried this as well. I followed the instructions here:
https://support.google.com/pixelphone/answer/2852139#zippy=%2Cif-your-phone-is-off

However, holding down the down volume button starting with the 'G' logo, the phone winds up in the Fastboot bootloader. I don't think that Graphene loads at all, or if it does it's not far enough to enter safe mode.

Johnnyloans

bchall

Maybe youre pressing the volume button too soon?

Hold volume down right after the screen for "youre loading a different operating system" goes away.

bchall

Johnnyloans

It's a good thought. I have definitely waited until after the screen for the "different operating system" is displayed. The Google documentation I linked says "When the animation starts, press and hold your phone's volume down button." But the boot animation for Graphene never starts, just the 'G' logo. Then the screen goes black, and then the phone restarts. So I depress the volume down button after the G logo appears, but I suspect the phone just restarts anyway, and then it enters Fastboot.

Johnnyloans

bchall

Hold volume down immediately after "loading a different operating system" goes away.

It'll be on the G or google screen.

At the grapheneos animation is too late. Those instructions are for stockOS

bchall

Johnnyloans

Thanks. I tried many times, starting at different points, but I don't think it ever reaches the point of loading GrapheneOS to be able to enter safe mode.

I also finally tried factory resetting the phone, and later loading the OS again through ADB. Neither worked; the behavior is the same as before. I think this is a hardware failure unfortunately.

Because the bootloader is locked, and OEM unlocking is not enabled, I can't follow the instructions to reinstall from scratch. Unlocking the bootloader in this state would require a booting OS.

At this point, I will have to see about replacing the device. It is out of warranty but I will try a claim also. Thank you all for your help!