[Solved] Xiaomi Redmi 7A: Turns on and off in a loop - causes and possible solutions

Since yesterday the phone turns on and off every few seconds - like in a loop. It wasn't flooded or dropped, the display works fine. Once the inscription Miui is displayed, once the android system. I managed to enter the service menu, where you can do a reboot or format the system, but nothing helped. I read on the net that it may be the fault of the SIM card, software, or the battery, which does not hold the voltage - but it is not swollen. It also worked in a loop at night, the display is still on until now. Unfortunately, it doesn't get to that point where you can log in. Regards

For starters, check with the ribbon of the side keys disconnected. In this case, you just need to raise the head plate a bit so that it does not come into contact with the tape.

It could also have gone into bootloop, board corruption.

For starters, do what blahfff colleague wrote. Next, check the battery, just because it's not swollen doesn't mean it's working.

blahfff wrote:

For starters, check with the ribbon of the side keys disconnected. In this case, you just need to raise the head plate a bit so that it does not come into contact with the tape.

I disconnected the battery, then picked up the motherboard. Unfortunately, no changes. Android is running in a loop all the time.
Regards

Possibly a battery but probably not. If you have nothing left to lose, try reloading the soft. If that doesn't help, it's most likely a faulty board.

winmap wrote:

Possibly a battery but probably not. If you have nothing left to lose, try reloading the soft. If that doesn't help, it's most likely a faulty board.

But first you need to enable developer option on your phone, and I don't have access there. How to do it from the computer? I've been looking around and can't find anything specific. However, I downloaded the mi unlock program to unlock the bootloader. The program starts, detects the phone, but does not unlock because the USB port is not enabled in the phone settings.. I also registered on the Mi Xiaomi account.
I will try Xiaomi ADB and MiTool again. Unfortunately, MiTool is asking for USB to be turned on. Is there any pc program that will enable it?

I used the Miflash program, downloaded a few ROMs, unzipped. When I want to upload a system, an error pops up in Miflash - can not find file flash_all_except_storage_bat. What to do with it next? I read that you still need to somehow unpack and process the compatibility folder, but I don't know how to bite it.
What system to try, Europe, China, Russia, India? How to check which system is for my phone?

winmap wrote:

Possibly a battery but probably not. If you have nothing left to lose, try reloading the soft. If that doesn't help, it's most likely a faulty board.

The new system cannot be uploaded because the phone asks for the Xiaomi account number. Unfortunately, I do not know it, and my son claims that he did not wear any.
I sent an e-mail to Xiaomi's central service requesting deletion of my account. They asked for the IMEI number of the blocked phone and the number of the SIM card. I sent it and am waiting for a response.

Probably assumed when configuring the phone. It's a hard thing. Only they can help. Of course, you can bypass it, but it can end badly, there are ways ... I hope the phone is not just a left one ... if you prove it to support, they will unlock it 👍

winmap wrote:

Probably assumed when configuring the phone. It's a hard thing. Only they can help. Of course, you can bypass it, but it can end badly, there are ways ... I hope the phone is not just a left one ... if you prove it to support, they will unlock it 👍

Possibly he did, but not necessarily. You can skip this step and do it later. They can delete everything, I don't care about the data from the phone, nothing special and important was there. What "left" phone? I have the original box with IMEI numbers 1 and 2, serial number, receipt from the store, phone number that has been in this phone from the beginning. Would anyone other than the owner have this data?

Added after 2 [hours] 28 [minutes]:

They replied to my email and directed me to the Xiaomi service. Unfortunately, the service is paid PLN 115. I probably won't use it, the phone is not worth it. In several points with telephones, I was offered to unlock and additionally upload a new system for PLN 100. So unnecessary waste of time and headaches.

As I wrote. I will not use the unlock for PLN 115 on the website. Maybe someone will buy it who can handle it.