How to boot my FP4?

Help Fairphone 4
,
1

Hi everyone,
I’m posting here because I desperately look elsewhere for a fix. Sadly I haven’t anything.

So here’s the issue.

Both my power and volume buttons are done. It happened a few month ago. I wasn’t much bothered about it since I found a way to set the volume up and down without using the side buttons.

One week end ago, I accidentally switched off my phone. And I can’t restart it since :

  • My power button doesn’t work. I thought it was because some dirt got stuck between the button and the contact push button. But I cleaned it and nothing changed.

  • I didn’t activate the developer mod on my phone, which means I can’t use ADB to boot from my Linux Distro

It’s really nerve breaking because I can see the phone working when I plug it.

I checked, fixing the volume button means sending it back to Fairphone team, since the volume button is fixed on the motherboard, a piece, sadly, not available for self repair.

I heard about something called “Jig cables” which used to force recover boot on some Samsung Qualcomm chipset devices. But I understand that those cables are old tech since they are mini USB and not USB C.

So, I’m open to new ideas.

J’attends aussi vos propositions en français :baguette_bread:

Ich freue mich auf deine Rückmeldung, Kollege! :beer:

2

Ok, this is a tricky one, but after some trial and error, I was able to get my FP4 to boot without any button presses. The process is as follows:

  • Remove the battery of your phone and reinsert it, in order for the phone to 100% completely have shut down
  • Connect a charging cable to the phone and be ready, to disconnect it very quickly
  • Once display shows the Fairphone logo, immediately disconnect your charger, even before the phone vibrates
  • If you were fast enough, the phone should now boot normally instead of only displaying the charging screen

Here’s a video of me doing it. Unfortunately I only had a bad webcam to record, but it should make the process very clear: Watch demo | Streamable

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3

Zalamander, you are my hero!
It worked!!!
Thank you so much!!!

I’m gonna be able to recover all my contacts and chat history thanks to you!!! :pray:

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4

Very very glad, I could help you.

I’d still try to get those buttons repaired via Fairphone pretty soon, or at least you could maybe perform regular backups, in case something else fails in the phone, without a workaround being available.

Best of luck and have a nice day.

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Me reading your post:

image
image582×404 34.9 KB

How the hell did you even figure this out?

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Hahaha, well I just played around with different sequences of connecting the charger and removing the battery. I thought that there might be a way to trick the phone into thinking, that it crashed and it would therefore attempt a direct boot into the OS.

But after I got one or two unreproducible random direct boots, I figured out, that the “bootup signal” when connecting a charger and the “check if we should just display the charging animation instead of direct booting” are far enough apart, so that I arrived at the solution I posted.

Just my curiosity (I though it was a fun puzzle to solve), some trial and error and a pinch of theory crafting, I guess. :smiley:

1 Like