Hi,
I thing , it may be getting i/o chip short .....because keyboard is connect to i/o chip.
Try for this methods
1. Remove battery form laptop, connect power adapter then on now,,,,,, if not..:roll:
2.press & hold power butten 2 min with connect battery....if not :roll:
3.finally replace i/o chip :-| (better give to laptop chip level service center.....for this,, )
Don't remove or plug any i/o parts (keyboard, touch pad ,some model laptop battery, camera ,)