after the update to a13, which ran flawlessly, every now and then (once a day) the screen turns white. Completely.
The OS still runs. Calls, reminder-peeps, all runs in the invisible background covered by the white shining display… No click on physical buttos, no gesture, nothing helps to get rid of the white display… Except: battery out, in again, start the phone… the display works as usual till the next unknown event, which turns it white again…
I recommend you enable USB-debugging in the developer options, install adb on your computer, connect the device, and select the checkbox to always allow USB debugging from this computer. This way you’ll be able to access the device via adb from the same computer without having to confirm any popups next time.
When the problem occurs again, connect the device to the same computer (preferrably on the same USB port) and execute the command adb exec-out screencap -p > filename.png in the terminal. This will create a screenshot of your phone’s screen and save it to filename.png on your Computer.
If this works and some useful content (e.g. an actual screenshot) is displayed, the screen is rendered correctly in the background and it’s likely an issue with the hardware connection of the display to the mainboard. In this case try removing the screen, cleaning the contacts, and reinserting it into the phone.
If the image is white, it may be some software issue. We’d have to explore this further.
If the command doesn’t work, post the error message you get.
If the image is black that may have multiple causes - one of which being that the screen is turned off. In this case try hitting the power button and execute the command again. If you get the same result it may well be a software or hardware issue, so you could still try to remove and reinsert the screen.
Another thing you could try is connecting an external display via USB C and see if it displays something useful, or if it is also white.
Just to clarify: If you call the Phone while the screen is white, you are able to take the call (e.g. via or connected headset or some physical button), and you can talk to the other person normally?
Also, since calls still work, you might as well try if the hardware-button-based screenshot shortcut still works. Just hit the power and volume-down button at the same time and see if you hear the screenshot sound (if enabled). Then check if a corresponding screenshot appears in your gallery after a forced reboot. (Or check your screenshot folder via adb without rebooting.)
Oh, and one more thing: Enable ‘Show taps’ and ‘Pointer location’ in the developer options and see if you still see the corresponding overlay when the screen turns white next time.
Also (although your symptoms are a bit different) a bunch of people have been experiencing frozen screens on their FP4 since the FP3 update, so you may also want to read and follow the following threads:
Additionally, there’s a thread about random FP4 reboots that occur since the update. It also seems like a different issue, but I’m not convinced it can’t have the same root cause. The guys over there have identified 5G as a likely common culprit. So maybe following that thread and experimenting with disabling 5G would also be a good idea:
Thanks for your replies @AndreasChris ! I had not much time to read through your linked threads and even less time to start USB-debugging. The weired behaviour of the freezing screen still existed. I am now trying to live with the workaround “screen rotation turned off”. No issues since then… I remember a freezing event, when I rotated the phone when simultaniously turning it on. but could not reproduce it…
I will contact FP Support to look after that issue.