[SOLVED] How to fix the Bootloop issue on Sony Ericsson Xperia Arc S LT18i usually brought about by switching on Bluetooth

The Sony Ericsson Xperia Arc S LT18i, an excellent phone of its times, is still a pretty decent phone to live with with all that Sony goodness in it.

The only sadness is that the item is out of support - both on the software as well as hardware sides, primarily because Sony and Ericsson parted ways.
The last available software update (Build number 4.1.B.0.587) is based on Android 4.0.4, and works good except for a few critical bugs that the unsupported users now have to live with.

One of the biggest problems is that the phone enters a 'bootloop' (reboots, after some delay turning the screen on, shows a black screen with the Sony logo, and a bit later, another screen with the Xperia logo, and then restarts, and this keeps happening again and again until you pull out the battery to power it off).

None of the normal stock methods seem to be able to fix this - hard resetting / recovery mode / PC Companion mode /....
Thanks to Androxyde's Flash Tool (www.flashtool.net), we now have the following working method to fix this.

Note that this will wipe all your data - this does a factory reset to the phone. Given the currently useless state, that seems a pretty good bargain. :-)

0. Make sure your phone battery has enough charge to complete the flashing process. Else, you might end up bricking the phone irreversibly. Keep it charging for around 1 hour or more - that should give it enough juice to live through this.
1. The flashtool works great on Windows 7.
2. Download the flashtool utility and the firmware from:
Flashtool Utility: Download the Windows version from http://www.flashtool.net/downloads.php.
Firmware for LT18i (LT18i_4.1.B.0.587_Generic Global World.ftf - 379MB - hosted on Google Drive): https://docs.google.com/file/d/0B-EZb_6TCqCiWThCcWdTNXFmQnM
3. Install the Flashtool utility by opening the downloaded installation file.
4. You Exit Sony PC Companion and any other Flashing software if you have them open / running in the background.

5. Power off the device by pulling out the battery.
6. Insert both a sim card, and an SD card.
7. Put the battery back in. DO NOT SWITCH IT ON OR PRESS ANY BUTTON.
8. Now start the FlashTool utility from the Windows "Start" menu.
9. Wait for the application to sync devices from Github.
10. Once that is over, keep the Back button on the phone pressed, and connect the USB data cable. The indicator LED, near the micro USB port on the phone, will show a green color.
11. Click on the Flash button (the one with a lightning symbol in the toolbar of the application).
12. In the 'Bootmode Chooser' dialog box that comes up, select "Flashmode" and click OK.
13. In the 'Firmware Selector' window that opens up, against 'Source Folder', select the folder where you have downloaded the firmware file to.
14. Now click the Flash button.
15. If they ask you to disconnect and reconnect the cable, do as we did in the above steps, and following the instructions shown.
16. Now when the log window shows "INFO - Flashing Finished.", and "INFO - Please unplug and start your phone", disconnect the USB cable, and switch on the mobile phone.

That should do it. You should now see a fresh and working OS booting up.

Flashing Steps (Screenshots):

Let me know if this didn't work for you / if you get stuck somewhere. I will try my best to help you out.

Happy Flashing!


Hi, I'm trying to follow your guide to fix my Xperia Arc S, however everytime I click the flash button (step 14) the Flasher returns INFO - Flash canceled. Any ideas what is causing this or how to get around it?
Thanks for any assisstance you can provide


Hi there, my xperia arc s has been rebooting its self randomly and since i turned on bluetooth it is now stuck in the reboot loop you are talking about in this article. My question is, what aditional tools/software do i need to do this reboot. Also am i required to change any settings on my phone. This would be a problem due to me being unable to turn it on and go into the developer settings.
Thanks, looking forward to hearing back from you.

Tried with flashing the phone. but flash process couldnt be completed due to errors.
11/009/2016 11:09:43 - INFO - Reading device information
11/009/2016 11:09:53 - INFO - Unable to read from phone after having opened it.
11/009/2016 11:09:53 - INFO - trying to continue anyway
11/009/2016 11:09:53 - INFO - Start Flashing
11/009/2016 11:09:53 - INFO - Processing loader.sin
11/009/2016 11:09:53 - INFO - Checking header
11/009/2016 11:09:53 - ERROR - Processing of loader.sin finished with errors.
11/009/2016 11:09:53 - INFO - Ending flash session
11/009/2016 11:09:53 - ERROR - Error in processHeader : 22 : The device does not recognize the command.
11/009/2016 11:09:53 - ERROR - Error flashing. Aborted
11/009/2016 11:09:54 - INFO - Device disconnected
11/010/2016 11:10:08 - INFO - Device connected with USB debugging off
11/010/2016 11:10:08 - INFO - For 2011 devices line, be sure you are not in MTP mode
11/010/2016 11:10:31 - INFO - Device disconnected

same problem


hey to all...
you have to install old version of flashtool (flashtool- this one) it works 100%

I tried but its not working. What should I do now.

After Connecting my device, I am getting below error.

29/048/2016 22:48:17 - INFO - Flashtool Version built on 24-09-2015 22:00:00
29/048/2016 22:48:17 - INFO - Executing search strategies to find proxy selector
29/048/2016 22:48:18 - INFO - No proxy found for IE. Trying next one
29/048/2016 22:48:18 - INFO - No proxy found for firefox. Trying next one
29/048/2016 22:48:18 - INFO - No proxy found for java. Trying next one
29/048/2016 22:48:19 - INFO - Syncing devices from github
29/048/2016 22:48:19 - INFO - Cloning devices repository
29/055/2016 22:55:49 - INFO - Devices sync finished.
29/055/2016 22:55:56 - INFO - Device disconnected
29/056/2016 22:56:36 - ERROR - Drivers need to be installed for connected device.
29/056/2016 22:56:36 - ERROR - You can find them in the drivers folder of Flashtool.

Please suggest, what needs to be done

Maybe helpful

My first try to flash my Sister's ARC S ended terrible:

07/017/2016 21:17:29 - ERROR - Processing of system.sin finished with errors.
07/017/2016 21:17:29 - INFO - Ending flash session
07/017/2016 21:17:29 - ERROR -
07/017/2016 21:17:29 - ERROR - Error flashing. Aborted
07/017/2016 21:17:29 - INFO - Flashing finished.
07/017/2016 21:17:29 - INFO - Please unplug and start your phone
07/017/2016 21:17:29 - INFO - For flashtool, Unknown Sources and Debugging must be checked in phone settings

After this, the phone shows me a critical error and shuts off.

I thought that was it, time for a new phone. But then I had an idea for a last try. I started flashtool again and excluded system.sin from flashing. Now the phone is working properly and my sister will be happy to get it back.

I was getting
ERROR - Processing of system.sin finished with errors.
INFO - Ending flash session
ERROR - Error flashing. Aborted
INFO - Flashing finished.
And my phone was alos showing me a critical error when I tried to turn it on.
So I also
- started flashtool again
- and excluded system.sin from flashing in the firmware selection window

Then, the flashing finished successfully and the phone installed a new system on the first boot.
But I had to unlock the boot first, for it to work.

To unlock the bootloader refer to https://developer.sony.com/develop/open-devices/get-started/unlock-bootl...

In a few words you have to:
- Download and install the Google USB driver from https://developer.android.com/studio/run/win-usb.html
- Download the Sony Fastboot driver from https://developer.sony.com/develop/drivers/
- Unzip the USB Driver and replace the file usb_driver/android_winusb.inf by the Sony Fastboot driver android_winusb.inf
- Download the Android Platform Tools from https://developer.android.com/studio/releases/platform-tools.html
- Remove the phone's battery, wait 5 secs and put it again
- Connect the phone with a USB cable in fastboot mode (see https://developer.sony.com/develop/open-devices/get-started/flash-tool/u...). For the xPeria Pro, it means press the menu button while connecting it to the computer via USB
- Windows will identify a Bootload device, but will fail to use a proper drive
- See https://developer.android.com/studio/run/oem-usb.html#InstallingDriver
- On the start menu > Computer > Right click on Manage > Devices > Browse my computer for driver > Select the Google USB Driver folder
- Unzip the Platform Tools and run `fastboot devices` through Command Prompt (Your device should appear in the list)
- Get an unlock code selecting your model in https://developer.sony.com/develop/open-devices/get-started/unlock-bootl...
* Input your device's IMEI code in the indicated field to get the unlocking code
* Use this code to run the following command `fastboot -i 0x0fce oem unlock 0x<insert your unlock code>`
- Now your device should be unlocked
- Remove it and turn it off removing the battery

Dear antojose,

You are a life saver. I was worried about my Arc S, which have this boot loop problem after turning bluetooth on. And to make it worse, Sony stopped updates for PC Companion.

Your flash tool worked fine. Much Appreciated..

Thx)works great for me.One note only- create special folder for firmware,Fashtool will find it easirely.

Thank you !! Be blessed. Worked for Xperia Ray st18i
I did have to select a couple of drivers (not mentioned in your step-by-step)
and had to fined the suitable firmware for my Xperia.

Hi! I was stuck with my Xperia Neo V, and I follow this step to repair my phone, this really work, just unziped the firmare and proceed to this steps... thanks.

hi,i have sonyericsson live with walkman and i followed the above guideline but the bootloop persists.
what should i do next please? kindy send solutions/recommendations to my inbox java2i@hotmail.com.
thanks a lot

Thank you very much! It worked on my experia Lt15i. It saved my money and time, I'm really thankful for this dude

i get the error occurred during statup, help!

Why the firmware file is in your trash?

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