Solved! Problems with laptop keyboard.

[AlanGetar]

Hello! Today my stepmoms laptop felt into some strange problem i can't resolve by myself.
So as the title says, laptop keyboard is not working. (But power button which integrated into keyboard works fine)
I tried all common ways of resolving this problem, reinstalling drivers, rollback latest windows updates, even got something to do with registry but nothing worked.
I even runned a lenovo diagnostics tool and the result is 'PS/2 keyboard unit WARNING' The app detects one ps/2 slot connected keyboard, but that's all.
Safe mode is not helping either.
I think it's a hardware issue because i can't even move in bios.
The laptop is Lenovo ideapad 120s-14iap, it's a budget device from lenovo.
Keyboards connected by usb work like they should, no complains about that.
I even tried reconnecting the keyboard connector (if i actually found the right cable)

https://imgur.com/KSqckor

View: https/imgur.com/KSqckor

The power button is not working when connector is disconnected so it's conn. cable is functioning.
Is there any ideas how to fix this.

 

[hang-the-9]

Try a new keyboard.

 

[AlanGetar]

Try a new keyboard.

Well i think i can't run from this anymore, but this will take a lot of time, because i never bothered with fully disassembling a laptop.

 

[AlHuneke]

I agree. The problem is likely the keyboard but there is also a chance the interconnect cable is bad or the interface circuitry on the motherboard is bad. Any of those situations are possible.

If you do dismantle your laptop, make sure you follow proper ESD precautions. For many machines, you can find disassembly instructions on youtube. Make sure you find instructions for the exact model. You may also be able to find a service manual for the machine. That is the best choice as the manual writers know what they are doing. No always the case with youtube. Be very careful unplugging connectors. There are various ways there work, but there is usually some sort of release tab. Keep track of which screws go where. Sometime, a different length screw will be used and you need to get it back in the right location.