Unlock screen is black upon unlock attempts

[Will Allen]

Hi. I am having issue where phone will not come out of lock screen. Buttons light but screen stays black. I can reboot and use phone so I know it is not hardware. I can still blindly touch screen and maybe get past lock but stays black til I reboot.

 

[Will Allen]

I recently upgraded Samsung galaxy S5 to lollipop att ota.

 

[ironass]

Try wiping the cache partition in Recovery Mode as per #1.3 of S5 Lollipop Update Problems - Dummies Guide