Inbuilt keyboard stops responding randomly

[Abhi_245]

I have a DELL Inspiron laptop it's inbuilt keyboard gets disconnected or stops responding randomly I don't know, but still my touchpad works and I always have to logout and sign in again to make the keyboard again working.

[stevef]

Do you have (or can you borrow) a USB keyboard that you can plug in when the built in keyboard stops working ?
That may allow us to do some diagnostics.
When it stops working and you logout and log in again does the in built keyboard allow you to enter a password ?

[Abhi_245]

Do you have (or can you borrow) a USB keyboard that you can plug in when the built in keyboard stops working ?
That may allow us to do some diagnostics.
When it stops working and you logout and log in again does the in built keyboard allow you to enter a password ?

Yeah , when I plugin the usb keyboard after pressing random keys then both the keyboard starts responding. And when I logout it allows me to enter the password.

[stevef]

OK, if it starts working again by simply by logging out or plugging in a USB device something odd is happening.

Next time the built in keyboard stops responding estimate the last time that you knew the keyboard to be working.
Plug in the USB keyboard and note the time you do this.
Use the USB keyboard to open a terminal by pressing Ctrl, Alt and T together.

Maximise the terminal window, then
Click Edit - Preferences
Under the General tab look for the 'Scrolling' section
Select the 'Unlimited Scrollback' option
Click 'Close' on the Preferences selection.

At the terminal prompt type in the command below followed by return.
In your command, replace the 'since' hh:mm with the estimated time that you knew the inbuilt keyboard was working.and the 'until' hh:mm with the time you plugged in the USB device.

Code:

journalctl -b --since hh:mm --until hh:mm --no-pager

This should display the contents of the log between the since and until times you specify
You can widen the time window if needed but we want to see if anything was logged when the keyboard went off line.

Scroll back to the start of the log and select/copy all the log entries.
Paste into a text file so you can review it and paste it back into the thread.

[Abhi_245]

I have attached the result of the code.
  1.txt (Size: 3.53 KB / Downloads: 2)
Just removed some of these lines Oct 25 13:56:13 Inspiron kernel: IPv6: MLD: clamping QRV from 1 to 2!

[stevef]

The log shows the USB keyboard being plugged in but nothing (obvious to me) about the in built device.
If you are sure this log should have captured the whole off line/on line of the in built device we may not have anything logged, but we can try looking a bit wider.

Please reboot the system and then wait for a failure. Use the USB keyboard as before and run this command after a failure. It should show events relating to input devices. No need for the time qualifiers as we want to see all matching events.

Code:

journalctl -b | grep input

[Abhi_245]

i guess this log 
  2.txt (Size: 3.92 KB / Downloads: 1) only shows the disconnection of the usb keyboard and nothing useful. I got this log after my keyboard stopped responding 2 times.

[stevef]

Can see the in built keyboard coming online by 09:15:05, then the USB keyboard at 09:19:14.
If the inbuilt keyboard was working and went offline between those times nothing matching 'input' got logged.

My next step would be swapping hardware (if possible) or looking for a better workaround to force the inbuilt keyboard back to life.

[Abhi_245]

Got a better solution, while I was resizing the terminal tab it again started to work fine.