My grandson has had his iPad mini same as mine for 2 years . All of a sudden it won't switch on . Battery is fully charged . Any ideas what could be wrong .?
If it won't switch on how do you know it's fully charged? If completely flat it won't even light up when plugged into a charger, plug it in (preferably the mains) for at least an hour then check it again.
If the battery isn't flat...Hold both the home button and the wake/suspend button down at the same time. You should see the Apple logo appear on your screen after holding these buttons down for several seconds, which means your iPad is booting up and should be good to go in a few more seconds...
Could always be a rogue process causing it to go flat very quickly, once it has some charge then Jomlett's suggestion is good, then double click the home button to get to the running apps, make a note of what is running and then close them all down. Once fully charged disconnect and periodically check to see what charge is left, if all appears ok then one can either try and work out what caused the problem or just carry on as usual.
Thanks for replies . Jomlette we have tried that but no response . Will have a look when I see him tomorrow and see if any life comes up and try from there as you have suggested fitz .