Sony Xperia XZ3
It's not possible to turn on my phone
Solution 3 of 3: Your phone doesn't turn on correctly
Before you can turn on your phone, you need to insert your SIM into your phone.
Press and hold On/Off until your phone is turned on.
If you're asked to key in your PIN, do so and press the confirm icon. The default PIN is 1111.
Press and hold On/Off until a pop-up menu is displayed.
Press Power off.