Phone is detected by "adb devices" but not detected by "fastboot devices"

[ruhrohs]

Phone is detected by "adb devices" but not detected by "fastboot devices"

I purchased a used P3a XL from Swappa. I would like to install a custom ROM. As we all know, in order for me to do that I need to unlock the bootloader. I think the phone is a Google Edition (checked SKU on box against what is sold in stores).

I have done quite a bit of research before posting here and think I have the process correct. I have enabled developer mode and toggled the OEM unlock option. I am able to "adb devices" and see the phone on my computer terminal. I "adb reboot bootloader" and the phone reboots in to "Fastboot Mode". When I do "fastboot devices" nothing shows. When I boot in to fastbootd (via stock recovery) and execute "fastboot devices" I can see the phone. I execute "fastboot flashing unlock" and it fails with "fastboot flashing unlock failed remote: unrecognized command flashing unlock".

I have tried this on my PixelBook with Linux installed and on my Ubuntu lab machine. Both of those machines give me the same results. I tried with my Windows 10 laptop, but the phone isn't detected by any of my USB-C to USB-A cables.

I have factory wiped the phone a few times and attempted the steps above, but it results in the same thing. Phone is not detected in fastboot. Interestingly, I am able to sideload the latest OTA (QQ3A.200605.001, Jun 2020) without any errors. After sideloading the latest OTA, I am still unable to unlock the bootloader.

I suspect one of two things:

1. 1. The phone is a VZW/Sprint/T-Mo edition. Even so, VZW edition can be unlocked. I tried that method (found an XDA thread to do that).
2. 2. Something is wonky with the phone (bootloader software)

Unfortunately, since I bought it second hand, I do not think Google would honor the hardware warranty to issue me an RMA.

What do you folks think may be an issue?

 

[Tulsadiver]

I purchased a used P3a XL from Swappa. I would like to install a custom ROM. As we all know, in order for me to do that I need to unlock the bootloader. I think the phone is a Google Edition (checked SKU on box against what is sold in stores).

I have done quite a bit of research before posting here and think I have the process correct. I have enabled developer mode and toggled the OEM unlock option. I am able to "adb devices" and see the phone on my computer terminal. I "adb reboot bootloader" and the phone reboots in to "Fastboot Mode". When I do "fastboot devices" nothing shows. When I boot in to fastbootd (via stock recovery) and execute "fastboot devices" I can see the phone. I execute "fastboot flashing unlock" and it fails with "fastboot flashing unlock failed remote: unrecognized command flashing unlock".

I have tried this on my PixelBook with Linux installed and on my Ubuntu lab machine. Both of those machines give me the same results. I tried with my Windows 10 laptop, but the phone isn't detected by any of my USB-C to USB-A cables.

I have factory wiped the phone a few times and attempted the steps above, but it results in the same thing. Phone is not detected in fastboot. Interestingly, I am able to sideload the latest OTA (QQ3A.200605.001, Jun 2020) without any errors. After sideloading the latest OTA, I am still unable to unlock the bootloader.

I suspect one of two things:

1. 1. The phone is a VZW/Sprint/T-Mo edition. Even so, VZW edition can be unlocked. I tried that method (found an XDA thread to do that).
2. 2. Something is wonky with the phone (bootloader software)

Unfortunately, since I bought it second hand, I do not think Google would honor the hardware warranty to issue me an RMA.

What do you folks think may be an issue?

Sideloading is an adb function, not fastboot. Make sure you have the lastest Android platform tools. This doesn't mean you can unlock the bootloader but to get fastboot working.

 

[41rw4lk]

Also make sure you have the oem cable or at least a decent cable, and use a 2.0 port if possible. I've seen other a/b devices refuse to work or give half commands with 3.0+ ports. What does it says underneath oem unlocking in dev settings? I've attached the latest adb/fastboot files just in case you might need them.

 

[ruhrohs]

Sideloading is an adb function, not fastboot. Make sure you have the lastest Android platform tools. This doesn't mean you can unlock the bootloader but to get fastboot working.

I just updated my Ubuntu machine with the lastest SDK, so both ADB and Fastboot were updated. The phone can be seen with "adb devices". It can be seen with "fastboot devices", but only if the phone is in fastbootd mode. Wouldn't this confirm that fastboot works on the laptop?

Also make sure you have the oem cable or at least a decent cable, and use a 2.0 port if possible. I've seen other a/b devices refuse to work or give half commands with 3.0+ ports. What does it says underneath oem unlocking in dev settings? I've attached the latest adb/fastboot files just in case you might need them.

I am using a PixelBook with the original USB-C to USB-C cable that came with the phone. My Windows laptop doesn't see the phone at all

OEM unlock option is enabled.

 

[Tulsadiver]

I just updated my Ubuntu machine with the lastest SDK, so both ADB and Fastboot were updated. The phone can be seen with "adb devices". It can be seen with "fastboot devices", but only if the phone is in fastbootd mode. Wouldn't this confirm that fastboot works on the laptop?



I am using a PixelBook with the original USB-C to USB-C cable that came with the phone. My Windows laptop doesn't see the phone at all

OEM unlock option is enabled.

As far as your window laptop, you might try installing usb drivers.

https://developer.android.com/studio/run/win-usb

 

[ruhrohs]

As far as your window laptop, you might try installing usb drivers.

https://developer.android.com/studio/run/win-usb

Yup, tried that as well. I even went as far as wiping one of my lab machines, installed Windows 7, copied and installed the command line tools only from here: https://developer.android.com/studio#downloads, but no dice. For Windows, I think it's a cable issue. I'm getting new USB-C to USB-A cables delivered tomorrow. Once I get them, I will try on my Windows laptop.

 

[ruhrohs]

Update to my issue...

Bought a 3 pack of Anker cables. Plugged each of them to my phone and to each of my Win 7 and Win 10 laptops. Both laptops are able to charge the phone, however the don't detect the phone for data transfer/USB debugging. I checked device manager, deleted/uninstalled all Android devices that were listed (including my first generation Pixel XL), rebooted my laptops and tried again. No dice... At this point, I'm chalking it up to the Pixel 3a XL phone itself and an issue with the hardware.

Note to self... Buy a brand new phone for an extra $100 and I would have saved myself over 4 days of troubleshooting an issue.

 

[thatsupnow]

Update to my issue...

Bought a 3 pack of Anker cables. Plugged each of them to my phone and to each of my Win 7 and Win 10 laptops. Both laptops are able to charge the phone, however the don't detect the phone for data transfer/USB debugging. I checked device manager, deleted/uninstalled all Android devices that were listed (including my first generation Pixel XL), rebooted my laptops and tried again. No dice... At this point, I'm chalking it up to the Pixel 3a XL phone itself and an issue with the hardware.

Note to self... Buy a brand new phone for an extra $100 and I would have saved myself over 4 days of troubleshooting an issue.

You do realise that you've got to change the USB settings for it to do data transfer right???

 

[kevinchristopherson]

You do realise that you've got to change the USB settings for it to do data transfer right???

my problem more than once, ashamed to say. after updating drivers and cords. then forgot to pull my notifications down for that last little line. it's a learning process though. (so they say).

 

[thatsupnow]

my problem more than once, ashamed to say. after updating drivers and cords. then forgot to pull my notifications down for that last little line. it's a learning process though. (so they say).

No worries dude even when you change default usb settings it still stays in charging mode

 

[ruhrohs]

You do realise that you've got to change the USB settings for it to do data transfer right???

Yup, I know that I need to change it to data transfer, however the phone isn't detected by either of my Windows laptops. The phone is only detected via ADB on my Chromebook. I can do an "adb reboot bootloader" and it'll accept the command, but "fastboot devices" or "lsusb" shows no devices.

my problem more than once, ashamed to say. after updating drivers and cords. then forgot to pull my notifications down for that last little line. it's a learning process though. (so they say).

Yup, my first gen Pixel XL will notify me when I pull down the notifications, but the Pixel 3a doesn't.


I ended up setting up the phone and used it for a fewdays. It works fine, however I'm used to running AdAway, AFWall, EX Kernel Manager, Greenify, High Brightness Mode, NapTime, Titanium Backup and Viper4Android. There are workarounds to enable Greenify and NapTime via ADB, but it's a moot point without the other root dependent apps.

 

[ruhrohs]

Updating this thread to close this out.

Bought a brand new Pixel 3a XL from the Google store. I was able to root without any issues on my Windows 10 laptop. I attempted the same exact process with the same USB port and USB cable for the Pixel 3a XL that I bought from Swappa, but it didn't work. This confirms my educated guess that it's a hardware issue on the phone.

The secondary market may soon be flooded with Pixel 3a XLs once the Pixel 4a is released. Before you get burned on a non-rootable phone, ask the seller how long they have owned the device and check the warranty on it. As of this post, you can check the IMEI Here: hxxps://store.google.com/repair (replace the hxxps with https).

Good luck!

 

[materics]

You need to download the google usb driver and update the Pixel 3 driver in Device manager with the usb driver. Then the computer will recognize the phone as a fastboot device while it's in bootloader.

 

[blondieboy]

For me what solved this was I wasn't adding the "platform-tools" folder to my path.

I was using "fastboot.exe flashing unlock"

But once I added to path and did "fastboot flashing unlock" it worked like a charm

 

[nomadk261]

On Linux, did you try sudo fastboot flashing unlock? This is the only thing that works for me. Sudo before all fastboot commands.

 

[Almasd]

In my case on Ubuntu 20.04, it was a USB 3.0 port problem. It was detect device with fastboot devices but other commands does not has a response. My laptop hasn't got a USB 2.0 port. Then I disabled internal USB 3.0 support in my BIOS and now fastboot is working normally. But all USB 3.0 support is stopped. It seems USB 2.0 hub is the better option. I will set back the BIOS setting later.

 

[th3y]

Yesterday i bought the G020B version, and the same happened to me while unlocking bootloader, fastboot keeps on <waiting for device> like if the phone was not even connected
I searched for a driver that could work and found this (For windows)
Basically, my system can't detect properly the phone because the driver was not 'updated'. (Even when i can use fastboot on other devices)
Hope it works for you or everyone here.