Although not in English, this should show the way. https://www.youtube.com/watch?v=ahTblmWz... Hope it helps.

My phone has the same issue, apparently this model is battery hungry. I manage it by leaving the Bluetooth and wifi turned off, unless it's on a charge cable, or I use the functions for a minimum period. Try eliminating all but those apps that you use often, also have a large capacity mini SD card inserted, move all apps that you use to it, and perhaps get a backup battery booster.

Next thing I would try would be to crack open the case (Provided there is no warranty), seperate all of the parts, ensuring that all cable , - or plug connections are seperated, get some aluminium foil, & foam rubber, press the rear of the board, - boards onto the al foil. This completly discharges everything, - allowing for a fresh re-boot. microscopically check for any corrosion, and clean off if any found. Re-assemble, plugging in the battery last. And then re-boot. Remember, - use fabric gloves, and keep yourself earthed. I have had more success with this aproach than failures.

1. Try connecting to a PC!If successful, 2. Connect to computer, & do a forced re-install of the map.