The keyboard on the laptop does not work correctly. What is it?

Question

Keyboard

Hello.
Lenovo flex 2 14'
Windows 8.1
The keyboard is behaving very strangely.
Some keys work, some don't. And sometimes, rarely, it starts to work. There are no errors in the system.
I did not reinstall the system, I cleaned the clave, I reconnected the cable, it was not flooded, there were no viruses, I updated the firewood.
wtf???
I want to figure it out without reinstalling.
There is no life sd at hand. To check the work in another shell.
It upsets that they removed safe mode in win8 (((

Answer 1

1. Disable at least all autoload via msconfig...
2. Try an external keyboard - will all keys work?
3. There is a safe mode in Win8: select the Restart item and click on it with the Shift key pressed.
Read more here

Answer 2

95% is a malfunction on the laptop motherboard in the keyboard harness. Take your laptop to a good service center