Some keys on the keyboard do not work

Problem description:

Some keyboard keys do not work. All remaining keys works normal. The laptop works properly with an external USB keyboard attached.
Reinstalling the operating system doesn’t help.

Possible cause:

1. Bad connection between the keyboard cable and motherboard.
2. The laptop keyboard failure.
3. The motherboard has a failed keyboard controller.

Possible troubleshooting steps and repair solution:

If some of the keys on your laptop keyboard stopped working, most likely you have a failed keyboard. Before you replaced the keyboard with a new one try reconnecting the keyboard cable on the motherboard. Reconnecting the cable might help.

If reconnecting the cable didn’t help, replace the keyboard with a new one. Most likely replacing the keyboard will fix your problem.

If not, most likely you have a faulty keyboard controller on the motherboard. This type of failure is not very common but it happens. In this case you ‘ll have to replace the whole motherboard.