Stuck in fastboot (resolved) crashing randomly (working so far)

[OVERW00D]

Hey guys,

I normally try to fix things myself and that works most of the time but I am really stuck now. Since I do not want to do any (more) damage, I want to ask you guys for help.

So as a nice christmas present my Mi 11 (Venus) decided to turn itself off several times today and yesterday. It started after installing a game (GT Manager) and crashing during the launch process. So after crashing once I didn' think much of it and when it happened again today (again in the startup of the game), I decided to remove the game. At that point the phone just turned itself off in shorter and shorter periods. In the end it didn't even recognize cables or anything anymore, no vibration, no fastboot, no charging, just nothing.

While playing around a bit and pressing buttons to get it to switch on, I managed to get into fastboot and boot twrp. Good or bad; I don't know, but I was just glad to do anything really, since I thought it's already a goner (motherboard saying goodbye was my guess): I decided to reinstall the latest stable xiaomi.eu Rom (13.0.9.0) which was already on the phone (and still on the phone drive) since late summer. The good thing: It stopped to turn itself off. The bad thing: it was stuck in a boot loop. So I decided to re-enter twrp and boot system via restart. Now it's stuck in Fastboot and is not going into twrp again. It gives me a load/authenticate error.

Any idea where I go from here? I tried reading threads and things I can do, but I just get really more confused. Initially I wanted to save my data since it's just so much work to get everything the way again, that I want. But at this point (while still preferring to save my data) I am just glad if I get the phone to work again.. Where do I go from here?

I really appreciate your help and sorry if it's somewhat obvious and I didn't figure it out so far. Just love this christmas present...

Phone Summary:
Mi 11 (Venus)
Rom: xiaomi.eu V13.0.9.0
Bootloader: unlocked
TWRP-version: ??? (first that came out after V 13 stable was available on twrp)

 

[Mark F]

As it's unlocked and you can get to fastboot, just flash the last or latest fastboot version of your ROM. Ignore trying by twrp, start with a fastboot ROM.

 

[OVERW00D]

Thanks for the help. Do I have to wipe data or can I use the update option?

Edit: After today I might turn out to be an alcoholic if this ever happens again. My phone is working again and I did NOT have to wipe my data.

But it was not straightforward. I can say that. After your tip, I went backwards to 13.0.8.0 via fastboot. That at least made the phone boot again but the apps were not working. Then I tried to install it again - same, apps not working. Then I went to 13.0.9.0 via TWRP again, but then I had the bootloop again. After doing everything basically the same way again - and failing, I wanted to try one more thing before wiping data. I installed 13.0.6.0 (the 2nd last stable), apps were still not working etc., went again to 13.0.8.0 (same) and then went to 13.0.9.0 once again. And look here, now it works. No idea how, no idea why, but does it really matter?

Thanks for the help @Mark F . I really hope it stays this way

Edit 2: It is still crashing randomly. Can I find out what is causing it?

Edit 3: It crashed two times rather quickly after booting up (after about 5min of operation), since then it stopped crashing (over 12 hours now). I will do a full backup just in case I need to wipe.

 

[Mark F]

You answered it yourself really. As long as you don't change ROM branch, as in stay weekly or stable etc, then no need to format.
If you do have access to twrp still, then I would reboot to twrp and wipe dalvik cache. If you restarts continue try wiping cache or even data and cache of each app but remember that wiping data will need you to put in passwords and data again. If you get to that level, it may be worth a format, but if it is a hardware issue causing the reboots, formatting will obviously not help unless it is a system app issue.
It's trial and error but at least you know how to get out of it sh6it happen again.

 

[OVERW00D]

Thanks! Very much appreciated. Happy Christmas holidays. Gonna monitor the system and take the steps accordingly

Edit 1: Seems to be some hardware defect. It just crashes randomly and ever so frequently. Did a few loops with different versions and now even format data. Long story short: It still crashes a lot and often it barely turns on. Only place it doesn't seem to crash is fastboot. Gonna send it back to tradingshenzhen. If it's somewhat reasonable they can fix it. Else they can have the brick.