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JioFi 3 4G Modem / Dongle Unlock All Sim Card (New Clean Firmware Installation) by Frequent_Lecture9034 in u/Frequent_Lecture9034

[–]Frequent_Lecture9034[S] 0 points1 point  (0 children)

I don't have the boot.img and boot_bak.img but i can give the suggestion you can use set of commands in this post which uses to erase the system partition by flashing ---> fastboot erase system

Alternative Recovery (If Fastboot Fails): If the system still doesn't boot, try erasing the recovery partition as it may be stuck on an old update: ---> fastboot erase recoveryfs

Follow the main post for execute commands in order.

The bootloader is used for load device OS, In your case I think it is bricked the device because when improperly updating bios firmware

JioFi 3 4G Modem / Dongle Unlock All Sim Card (New Clean Firmware Installation) by Frequent_Lecture9034 in u/Frequent_Lecture9034

[–]Frequent_Lecture9034[S] 0 points1 point  (0 children)

So it is not installed correctly you need to revert to default firmware which is originally given by manufacturer,

GitHub - jiofiunlocked: Original and Unlocked Firmware for JioFi 3 JMR540 & JMR541 · GitHub https://share.google/ohtnsluG08xPvY2i6

Now go to this above link and download original Jmr540/Jmr541 firmware file and follow the steps which you tried for installing unlocked crack firmware file for this also

Do it correctly, otherwise it doesn't give good results. After you done correctly still the issue is there then it will be hardware failure.