MTP not working on Pixel 3a XL after OTA-25 update

zlamalp

Hi,

it seems, that MTP is not working after the OTA-25 update on my Google Pixel 3a XL.

I'm not really sure that its the root cause, but I was using it a few days back, then I installed OTA-25 and a day later I can't connect to the phone to transfer my files.

I was trying to resolve this by myself few days, but with no success.

There is absolutely no error message on the computer side. No new device is shown in lsusb output, when phone is connected. Phone does charge from the USB, but it's simply not displayed in file manager.

It seems, that the phone is not advertazing itself properly to the PC.

I do have developer mode enabled, including ADB access, but no device is found for the adb shell command either.

Can anyone suggest where to look for some relevant logs on the phone? Is MTP running as some kind of system service I can check?

I was thinking about the possibility of trying to downgrade the version, but I don't know if it's possible and how to do it? I can change the release channel, but I reckon RC/Devel don't have a different image when OTA-25 is the latest version. Also (at least for now) I don't feel like installing Focal as I need fully working phone.

PS: Cable and PC are working. I tried it with different android/ubuntu phones.

MrT10001

@zlamalp install UT tweak tools and use that to toggle ADB on and off. The settings can be found on a drop down menu on the top left, under system. Toggle it between ADB and RNDIS.
reboot the device afterwards.

zlamalp

Hi, @MrT10001. Thank you for suggestion. I tried to toggle it and it doesn't change anything. Phone is still not visible to the PC. Both before and after the reboot

I also tried to just switch it to the RNDIS and reboot. But then on opening UT tweak tool again "MTP" was selected, so it seems the change is not actually saved or persist reboot.

L-00987

Restart your Pixel 3a XL and your computer.
Try using a different USB cable or port.
Check if the USB debugging option is enabled on your phone. To do this, go to Settings > System > Developer options > USB debugging.
Try connecting your phone to a different computer to see if the issue persists.

zlamalp

Hi @TandyNeoma,

I did this multiple times over the past days, no change.

2./4. I already tried this with a different PCs/ports and phones. Cable itself works, same for my PC.

I do have Debug enabled. I tried to toggle it, no change. But I noticed similar problem as when toggling MTP. When I disable the developer mode (debug), then this change is not persistent. After the reboot I still have developer mode enabled instead of disabled. I think this is not OK, phone should remember such setting.

It would be most helpful, if someone could share the knowledge, where such low level services like MTP keep their logs or how to check their actual status.

Craig

@zlamalp I'm having the same problem with Pixel 3a. My records state I updated to OTA-25 on March 30. I didn't notice I couldn't connect via USB cable to do backups until today.

I did notice my computer can recognize my UT phone via USB and ADB if I put it in Recovery Mode only. So, it's not a hardware or cable problem.

Running

sudo dmesg -w

shows nothing when I plug and unplug my UT phone via USB. Other USB devices do register.

I also posted this issue on https://t.me/ubports

zlamalp

Hi @Craig,

I can confirm your report. Phone is visible to PC when in recovery. It's strange, that device is using two different IDs/Names:

When in fastboot menu (power + vol. down)

Bus 006 Device 003: ID 18d1:4ee0 Google Inc. Nexus/Pixel Device (fastboot)

When in UBports Recovery

Bus 006 Device 004: ID 18d1:d001 Google Inc. Nexus 4 (fastboot)

I could see various USB related messages in recovery logs, but can't really tell what they mean.

I wonder if there is any way how to install older OTA and test this since Phone is not visible to ubports-installer.

Craig

@zlamalp This is not a solution for MTP, but a work around on the adb issue. I got this from some UT community members on Telegram.

Shut down the phone, then press volume down and power to get into recovery mode. From there, adb still works. Do

adb shell
mount /data

You will find your data inside the data directory and can push and pull, run backups, etc.

dln949

After updating to 20.04 I now am seeing this same problem on pixel 3.

Two questions:

How can I tell if this problem is being addressed by those people with the skills to address this? (I ask this in a positive way simply to know what the status is; my knowledge of such tech stuff is about 0.0.)
I also noticed that on the device I can activate "Developer Mode", but if I then leave that screen and then go back into that same screen right away, developer mode has been turned off for some reason. Is this a problem, and is it related to the mtp problem?

MrT10001

I have MTP working on my Pixel 3a(s) on Xenial and Focal.

Set a Passcode, I always use a 4 digit code for my convenience.

Enabled developer mode.

Rebooted device and Developer Mode is still enabled.

I do have Android Studio installed on my Windows 11 PC which gives me the latest Fastboot and ADB drivers.

Above are two screenshots from my Pixel3a of my "custom" image on home and lock screen. Transferred by MTP along with a custom ringtone.

I also use a decent quality USB-C cable for transfers.

arubislander

@MrT10001 MTP shouldn't be dependent on ADB and fastboot drivers though, should it?

MrT10001

@arubislander It shouldn't, but I got rid of some excess drivers on my PC (Motorola was one) and my devices stopped getting picked up in explorer (convenience). I Updated Android Studio and they all worked again. So I must assume ADB drivers on a PC will affect transfer of media at the higher level.

etdoughe

Same exact problem.. Was running OTA-23 on Pixel 3aXL, plugged my phone into PC (ubuntu 16.04), and Pixel 3a icon immediately popped up on applications bar. I clicked on this icon to backup all files from my phone. No problems. Upgraded to OTA-25, and when I plug phone back into computer (same cable same day), no icon pops up, and phone is not seen by lsusb or adb. Same issue whether developer mode on phone is enabled or not. I was hoping to experiment a bit with linphone but can't till computer recognizes phone again. Any help is greatly appreciated.

MrT10001

@etdoughe Try installing Android Studio and see if that works.

etdoughe

@MrT10001. Thank you for the suggestion. Unfortunately it didn't work. Any other suggestions are greatly appreciated.

MrT10001

@etdoughe I had it working through a windows 11 PC:

marlboro50

@zlamalp I have exactly the same problem on my Pixel 3a. I reported it a few weeks ago. USB not working. No matter what I do. It works perfectly well with my older Aqaris E5Hd. Same OTA 25, same cables. It makes no difference if I use my Desktop or Laptop with Ubuntu 20.04.

zlamalp

Hi,

just to let you know this problem has been solved for me by upgrading to 20.04 base (OTA-3). I had to re-enable developer mode after the upgrade.

For some reason device is weirdly named by lsusb, but transfering files works again, adb shell too.

Bus 004 Device 002: ID 1209:0003 Generic pid.codes Test PID