Q: Hardware issue post iOS 9.3 iPad mini 2

And that includes the latest version of iOS 9.3 that was just released (same number but a newer version for older iPads). Try it one more time. If that doesn't work mendonipadrehab can give you some good tips for taking it to a 3rd party repair site.

1. take it to an Apple Store for whatever they offer
2. take it to an Apple Authorized Service Provider for whatever they offer
3. take it to an independent  service legitimate business for whatever they offer