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Laptops don't come with a fuse box in the sense that all of the fuses are in one spot and they can easily be changed by the user (say like in a car). Fuses are generally soldered down to the motherboard in whatever area the maker has designed. While the T60 may have upwards of a dozen or so fuses, as far as having any of the LED status indicators being protected by one, this also does not happen. What is likely in the case of a malfunctioning light would be:
- a connector has worked loose; you have to find it and plug it back in
- the key is broken; usual fix is to replace the entire keyboard
- the LED has burned out; not usually the case but it's possible
- something else wacky on the motherboard; electrical failure or firmware issue
The caps lock indicator should work even without an operating system being loaded. Turn on the system, immediately press the F1 key a couple of times and the system should enter the BIOS menu (displays BIOS revision number, system serial numbers, CPU speed, installed memory, etc.). Press the caps lock key several times and see if the indicator works. Most likely it still won't but it's mostly a check to see if Windows is the source of the problem. You can then turn off the system by pressing the power button for about a second.
There is a diagnostic program available which can test each key on the keyboard. You will have to download a file, execute it (which creates a file with an .ISO extension) and then write that file to a CD-R or CD-RW disk. The program is called PC Doctor for DOS and can be obtained from here:
http://www-307.ibm.com/pc/support/site. ... MIGR-56222
Besides the CD writer, you will also need a program that is able to handle the .ISO file. It's a special file format that represents an "image" of the disk. You cannot simply write the file to the disk using Windows built-in support for writing data onto a blank CD. A free program which is able to write .ISO files is called CDBurnerXP and can be found here:
http://cdburnerxp.se
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