My keyboard just stopped working all of a sudden. I am not sure what the cause is, I just powered on the laptop and the keyboard isn't working.
I have tried installing updates using Lenovo Vantage but still, nothing happens.
When I disconnect the keyboard, I get the notification of Switching into Tablet Mode also when I reconnect the keyboard I get the message of exiting tablet mode but the keyboard doesn't light up and doesn't function.
I need assistance with what's happening.

Was there any resolution to this?

I am now having the same problem sometimes after a wake up. Restarting does not help but if I shut down and then power back up again the keyboard works again.

Very irritating.

https://www.youtube.com/watch?v=rNgT5ukau0k

I have the exactly same issue here. Called the tech support and was told need to buy a new keyboard since warranty is expired. Just 2 years, 20% of the machine value! Lenovo should recall the keyboard.

I am also having the same issue as my keyboard suddenly stopped working.  If anyone has any resolution, please post. 

Just had my keyboard replaced for backlight flashing issue and today it just stopped working. Raised ticket now, I've only got 5 months left really afraid that it is going to fail again.

Mine too, 3 mth after warranty is finished.

Any solution for this, pretty useless without the keyboard?

It really works with power down and restarting the computer. The company has spent already the money for a new keyboard, but I guess, this is the simple solution. I can confirm the method at least still working in 2022. 

Just ran out of warranty and this happened to me. Any solutions yet? Powering down does not work for me.