Few days ago my PS3 decided to stop recognizing my controllers. When I press the PS Button, nothing happens, regardless of whether or not DualShock is connected through a USB cable or Bluetooth. I've checked a few different controllers, but none of them work. How do I fix this?
Your Dualshock 3 controller might have lost its binding to your console.
Try resetting the controller by pushing the reset button (you will need something thin and long, e.g. a paperclip). The reset button is located on the back of the Dualshock 3, near the L2 button inside a small hole.
After that, resync the controller to your PS3 by first connecting it with the USB cable.
Perhaps try connecting the Controller, via packaged / 'came-with' USB-Cables, to the PlayStation: like @Luc_M suggested.
Or, maybe try re-charging from a computer's USB Port.
These suggestions come from standardised procedures. :)