Ghost ( key ) busting with Linux

Among laptops, it is common to come across the problem of stuck keys. Keys that continually send a signal even when they are not pressed, as a result of a short contact in the keyboard.

In most cases it is easy to find the offending key - just open a text editor and the output text will reveal the culprit with a long stream of repeated letters/numbers.
But, ghost keys are a bit difficult to identify - which is why they are so named. And these are usually the Function keys. The problem with having a stuck F2 is that it interrupts the booting process, unless another key is pressed after which things remain normal. Even normal working on the desktop is not effected in most cases, so you don't bother about it, untill you reboot the machine and have to nudge the system to continue from the interrupted state.

REcently I faced this problem, and the easiest solution to the issue was to use a live linux CD. Once the system starts to load itself into RAM, the log messages are displayed - this may not be the default behaviour in most cases, since a static loading page could be shown with a message to press any key to view messages, do so. The constant stream of output from the function key in the midst of log messages will give away the defective key. The output will be in a cryptic form and not "F4" or something similar, but comparing it with the output of all the Function keys will be adequate.

In the latest case, I had a tough time with the F10 key, with the only indication once the desktop was loaded was that the right click menu would disappear as soon as it appeared. With the live CD, I could find the output code and match it with F10. The F10 key was disabled permanently.

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