Help Nexus 7 2013 LTE in complete bootloop. No methods working

[NightEagle]

Ok, so my mum was playing on her Nexus 7, next moment it reboots and is stuck on the "Google" logo. This was the part where I decided to do some research on this particular problem. According to many websites, it was something to do with when you update to 5.0.2. But the Nexus was on 5.0.x for a while with no problems at all until now

Luckily, fastboot mode was still accessable, alongside the default Android recovery mode, but the recovery mode had a bunch of "cache" errors. I tried the simple methods by wiping data/cache, froze for about a minute then came back with another error message. It started to get more advanced. I then used Nexus Root Toolkit by Wugfresh. ADB/fastboot drivers were no problem at all, as I got them already from a 3rd party source. I tried to do the most easiest and obvious methods to fix it, which turned out I had to unlock the bootloader to do anything. I went to unlock the bootloader, and it asked me on the Nexus if I wanted to unlock it and I said yes. The Nexus froze and the command prompt did as well, meaning it was doing nothing to try and unlock it.

To be honest, I'm all out of methods and ideas to fix this, and this forum is my last hope. I'm possibly doing something wrong here, but I'd appreciate some help to fix this issue so I can get CWM and CyanogenMod on it to avoid this happening again.

 

[mydian]

If you can't unlock the boot loader you can't really do anything as far as I know. It sounds like the internal memory has been corrupted. Maybe someone more knowledgeable will have another suggestion but it doesn't sound good.

 

[NightEagle]

OK here is a screenshot of what the recovery looks like (I'll try and get more screenshots when I get home, Xenforo hates my phone):

As you can see, the cache doesn't seem to be working. Hope this helps

Also the fastboot mode:

Because of my kindle, it says:

Fastboot Mode
Product Name - deb
HW Version - rev_e
Bootloader Version - FLO-04.05
Baseband Version - DEB-Z00_2.44 0_0213
Carrier Info - None
Serial Number - 0a67c02f
Signing - yes
Secure Boot - enabled
Lock State - locked

 

[NightEagle]

If you can't unlock the boot loader you can't really do anything as far as I know. It sounds like the internal memory has been corrupted. Maybe someone more knowledgeable will have another suggestion but it doesn't sound good.

I can access the boot loader and recovery, but the recovery is extremely restricted because of the cache errors. Strange that I can't unlock it though

 

[mydian]

There are some threads on XDA with your problem. It happened a lot apparently with 5.0 but 5.0.2 was supposed to fix it. 5.1.1 had been out for awhile though. Anyway, the problem from what I've read was the internal memory gets corrupted and then it will hang on trying to unlock the bootloader. The only fix was a motherboard replacement.

Anyway, that's just what I've read. Obviously you should do your own research.

Good luck.