Bootloader unlock guide for US Xperia 1 IV
Sharing this here as I’m sure many people have been waiting for something like this.
This guide will allow you to unlock the bootloader on your US mmWave variant Xperia 1 IV (XQ-CT62).
Disclaimer, I have no affiliation with these tools or services whatsoever. That said, anecdotally I have used them and was able to unlock my own device. Proceed at your own risk!
This is using the new qunlock tool from Infinity Box. You need to buy a token from a reseller.
I used this reseller and it took a few days to get the email. https://new.networkunlocking.com/se...unter-Supported--qUnlock-S1-Unlock-Tool?pid=3
Another Xperia 1 IV owner used this reseller and got his token immediately, link here: https://gsmservice.center/resellerpricing/server
Download the tool (qUnlockTool.7z) from infinitybox here: https://dl1.infinity-box.com/00/pub.php?dir=software/other/qUnlockTool/
Archive pw is 1111
Run the tool, turn phone off. Click “sim unlock”, after putting in your token. Then, hold the volume down key on your phone while plugging it in to a usb port until the notification LED turns green and the tool recognizes it. Make sure you have the drivers installed from the archive before trying.
If successful it will say “calculating”, will generate the unlock for you server side, then write to the TA partition and flip the bootloader unlock flag to true.
When complete, unplug and boot into android. You will see “bootloader unlockable = true” in the service menu. Enable OEM unlocking in developer settings, then reboot to fastboot using ADB or by holding volume up while plugging in to USB with the device off, until the notification LED turns blue.
Follow the instructions for unlocking the bootloader on Sony’s website: select Xperia 1 IV, and generate the unlock code. Paste the unlock code into fastboot, then do fastboot oem unlock.
You do lose widevine L1 and you also lose the TEE key, so only basic attestation is working, as expected and as was the case with the Xperia 1 III as well.
Relocking the bootloader will restore the keys.
edit: added picture
Posted Apr 3, 2023, 12:29 AM UTC · edited