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Downgrade Lenovo P11 Gen 2 TB350XU from Android 13 to Android 12L
Disclaimer
- Only do at your own risk
- I'm not responsible for voided warranties or bricked devices
- I'm aware this isn't the best way to do this
- In some steps I'm not entirely sure what I did myself, but I did end up with Android 12 on my TB350XU
- Message me in the Android channel on the LaptopWiki Discord if you can't find necessary files, I will try to provide them to you
What you will need
- Lenovo Tab P11 Gen 2 Mediatek
- Mediatek SPFlashTool 6 https://spflashtools.com/windows/sp-flash-tool-v6-2216
- ROM files
- Windows PC
Where to get ROM
- You will need both of these
- TB350XU_S130348_240118_ROW.7z https://mirrors.lolinet.com/firmware/lenowow/Tab_P11_2nd_Gen/TB350XU/
- Lenovo-Tab-P11-2nd-Gen-TB350XU-23.zip (TB350XU_S020273_230717_ROW) https://www.needrom.com/download/lenovo-tab-p11-2nd-gen-tb350xu/ - VERY SLOW DOWNLOAD, it took me about 8 hours, so message me on LaptopWiki Discord
Flashing process
- Turn off your tablet
- Extract both ROM files
- Extract SPFlashTool
- We will want to flash the TB350XU_S020273_230717_ROW, but that package is missing some files
- Copy MT6789_Android_scatter.txt and MT6789_Android_scatter.xml and CheckSum_Generate.exe TB350XU_S130348_240118_ROW folder to TB350XU_S020273_230717_ROW\image
- Run the CheckSum_generate.exe file
- Open SPFlashTool in MTK_flash_tool_V6\MTK_flash_tool_V6\flash_tool.exe
- Into Download-XML load TB350XU_S020273_230717_ROW\image\download_agent\flash.xml
- If you generated the Checksum properly the ROM should load
- From the dropdown select Download Only
- DO NOT select Format All + Download, you might lose your IMEI number
- Click the Download button
- Connect you tablet (while OFF)
- The flash should take about 3-4 minutes
Now the hard part
- Here comes the part where I'm not sure what I did
- The tablet acts like it's bricked, it isn't responding to inputs, charger etc
- What got it out of this state was various combinations of holding the power button for half a minute, holding Power+Volume Up for half a minute, holding Power+Volume Down for half a minute and so on
- Power + Volume Down is Force Shutdown (on all other Android devices I have had it was just Hold Power), so hold that for about 30 seconds.
- If it starts bootlooping (Lenovo Android logo pops up, then it reboots), hold Power and Volume up.
- If you get a Fastboot prompt, you are okay, you didn't hard brick the tablet
- Turn it off by holding power button for 20 seconds or so
- Try the flash again
- I'm mentioning because this happened to me. Bootloop and a second flash = working Android 12 Tablet.