I merged your threads. Please consider registering on this forum so that you can actually respond within the thread you created:
https://forums.androidcentral.com/as...community.html
Ok, it was made in 2015, but it was released in 2013, and Google only guaranteed updates for about 2-3 years after release date for that device. I have two 2013 Nexus 7's, and the last patch they got was Aug 2016.
So are you sure it was a system update that happened when it shut down? Other possibilities include hardware failure, firmware corruption, and malware.