Keyboard shift key bug on Lenovo Thinkpad

Question

For some days now, I have a problem with my Lenovo Thinkpad T470p keyboard. Before all : I've already updated drivers and shutdown my computer.

Here are the problems :

• The light of the caps lock key is like 50% lighted up in permanence (see the photo). Of course, before, the light was off.
• When I hold the shift key and then press the space bar, it doesn't work.
• When I hold the shift key, and then press letters, some append 2 letters. For example, pressing shift + B appends "BT", shift + T appends "BT", shift + Y appends "NY", shift + N appends "NY".

It seems to be the only keys that have a problem.

The caps lock key in its normal state (abnormally 50% lighted up):

The caps lock key in its uppercase state (normal 100% lighted up):

Have you an idea of what could be the problem?

Solution

After the advices given by @AFH :

Try booting into the UEFI/BIOS and see if the problem exists there: this will eliminate any OS-related problems, including any form of virus infection.

AND

Remove the power plug and the battery, and leave completely unpowered for at least 30 seconds.

... the fact is : it is a pure hardware problem with the keyboard.

Comments

[AFH]

Try booting into the UEFI/BIOS and see if the problem exists there: this will eliminate any OS-related problems, including any form of virus infection.

[secavfr]

It doesn't seem so :l Light still light up.

[AFH]

In that case, it's probably a hardware problem. Does that model have a removable battery? If so, shut down, remove the power plug and the battery, and leave completely unpowered for at least 30 seconds. This may clear any lingering hardware settings; otherwise, it's a repair job.

[secavfr]

I've tried what you propose. Unfortunately, this seem to be a pure hardware problem... Thank you for your help anyway !