|I guess the battery is in good condition and fully charged?|
There is a 'reset all' function but you have to be able to access the menu in order to do it and I guess you can't do that.
When you remove the battery, leave it out for awhile, maybe even overnight. Then reinstall it and see if you can do anything with it. If so the reset option is MENU--SETTINGS--RESET ALL. That should also be explained in the manual.