(01-24-2023, 09:56 AM)Kevin Kofler Wrote: Hmmm, before I start with that, one question: I see I can enter EDL/QDL mode with the instructions from:
* https://github.com/Biktorgj/quectel_eg25...l-with-adb
* https://xnux.eu/devices/feature/modem-pp...adb-access
but is there a way to get back out of that mode without flashing a firmware?
i think no, beyond reboot and/or removing battery. however, if usb connection stays stable in edl/qdl mode, i think there is an issue with firmware.
03-12-2023, 05:17 AM
(This post was last modified: 03-12-2023, 09:44 AM by Kevin Kofler.)
So, to keep you updated: The last few weeks, the modem has been almost always down (or rather, disconnected from the USB bus). Sometimes, it has come up for a short moment, and the occasional SMS got delivered then, but it was immediately gone again.
Attempting to flash a new firmware is also not possible if the modem does not even show up on USB. But it all looks like a hardware fault anyway.
So unfortunately, the resolution is that I have to buy a replacement. I have ordered a new PinePhone from the EU store (hoping the 2 year warranty there will cover this type of defects – it should by EU laws). The defective one was ordered directly from the Pine Store because that was the only option at the time (April 2021, the EU store was opened July 2022).
For the record, it turned out that it is not just the modem: That PinePhone's USB subsystem is completely messed up. It fails to work even with JumpDrive (the computer cannot see it on USB), whereas the new one I just received works just fine with the same JumpDrive image on the same microSD card, the same USB C-A cable and the same computer.
So I will have to resort to WiFi to transfer my data from the broken PinePhone to the new one.
(03-20-2023, 01:12 PM)Kevin Kofler Wrote: For the record, it turned out that it is not just the modem: That PinePhone's USB subsystem is completely messed up. It fails to work even with JumpDrive (the computer cannot see it on USB), whereas the new one I just received works just fine with the same JumpDrive image on the same microSD card, the same USB C-A cable and the same computer.
So I will have to resort to WiFi to transfer my data from the broken PinePhone to the new one.
what i have looked the schematics, usb is in a soc chip. although other (physical) components or chips could be the cause as well. not necessarily conclusive, but this increases my feeling that we play some kind lottery game with quality of mainboard and soc chip.
Since this is definitely a hardware issue (which I cannot fix) and the replacement I bought works (which also means I am not going to attempt any further debugging), I am marking this as resolved.
(03-22-2023, 05:28 PM)Kevin Kofler Wrote: Since this is definitely a hardware issue (which I cannot fix) and the replacement I bought works (which also means I am not going to attempt any further debugging), I am marking this as resolved.
Have you tred the IMEI rebuild on the phone with modem issues?
https://themodemdistro.com/efs_recovery
a pretty easy fix from a running pinephone.
or file a bug
https://github.com/the-modem-distro/pine...sdk/issues
At least come around a bit commenting when you can since we need critical mass of experienced users.
12-11-2025, 04:28 PM
(This post was last modified: 12-11-2025, 04:29 PM by Kevin Kofler.)
The modem is operating just fine when I talk to it over the virtual TTY (well, to be honest, I have not tried it with the newer PinePhone, but with the first one, that was definitely the case), it just does not come up on USB, which is what breaks things, because everything expects the modem to come up on USB. Considering that there are also other USB issues (the external port not working for data), I think this is clearly a USB issue, not a modem issue.
(12-11-2025, 04:28 PM)Kevin Kofler Wrote: The modem is operating just fine when I talk to it over the virtual TTY (well, to be honest, I have not tried it with the newer PinePhone, but with the first one, that was definitely the case), it just does not come up on USB, which is what breaks things, because everything expects the modem to come up on USB. Considering that there are also other USB issues (the external port not working for data), I think this is clearly a USB issue, not a modem issue.
I have a PPpro where the modem comes up on most USB but not as a sound device, through all of the firmware changes.
but I can see in the modem's dmesg that it is not able to create the sound device. Even flashing to stock doesn't fix the issue. Frustrating as I just bought this replacement system board.
(01-17-2023, 05:50 PM)Kevin Kofler Wrote: [UPDATE: TL;DR: The resolution is that the hardware is faulty (in fact, not just the modem, but the entire USB subsystem except charging), and that I just bought a new PinePhone which works.]
Since late December (so for the last 3 weeks or so), I have been struggling with a strange issue on my PinePhone (Beta Edition). The modem keeps going down for some reason, making it just "disappear" from the PinePhone's point of view. eg25-manager tries to restart it, and sometimes it succeeds, but often the restart also fails, or eg25-manager gets stuck waiting for a long time and does not even try a reset even though the modem device is not visible to ModemManager or anything else (I cannot even see the device node). Sometimes, the modem does not even come up on boot, and even rebooting several times does not necessarily fix it.
It did happen in the past (before December) that the modem had to be restarted, but that was around once a day, and the auto-restart (in eg25-manager and ModemManager) had been just working for weeks now. (And I believe that was a known issue, which is also why the auto-restart had been implemented.) But now, the modem often goes down every 5 minutes, and the auto-restart does not reliably work anymore either. (Sometimes it does, often it does not.)
The first thing I would have suspected would be the latest software updates. (I run Manjaro Plasma Mobile, the one that was preinstalled on the Beta Edition, but continuously upgraded from the stable repository using pamac-gtk. FYI, Discover is just broken for system updates on Manjaro, so I gave up on using that one long ago, but that is not the issue here.) But if that were the case (i.e., if it were a software regression), the issue would have hit more users, would it not? Yet, I have not seen any other report of this happening. Or does anybody else see the same thing?
The behavior looks a lot like a wrong contact on the USB connection, but the modem is soldered onto the mainboard, is it not? So how can it possibly make a loose contact?
The remaining suspect then was the battery, also considering that the PinePhone modem is connected directly to the battery on the PinePhone. So I bought a replacement battery (a Samsung EB-BJ700CBE, which is documented as fitting) from a local retailer today. And well, yes, the battery fits, and yes, the battery works in principle. But the modem issue is the same whether I use the replacement battery or the original PinePhone battery (that I have now put back in), it makes no visible difference.
So at this point, I am stuck. I am completely out of ideas.
I am pretty annoyed at this point because I was using the PinePhone as my daily driver just fine, but now this issue makes it extremely unreliable (since without the modem, it is really just a tablet!) and I have no idea how to resolve the issue.
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PinePhone modem keeps "disappearing"
