First off: It was never a question about dismantling the keyboard, it was a question about there being a fuse on the light circuit on the keyboard. Because that would explain why ALL the lights died, but the rest of the keyboard working as normal.
Second: how strong is the fuse in-line there. is it a 5, 10 or maybe a 15 WATT fuse. The keyboard was RMA'ed pretty quick, but I asked due to the fact this happened when I moved it from my gaming PC to my work laptops docking on which I normally use a K63 at work without any issues.
Third: If there is a fuse in there, could be an idea to put under a cover so people could change it easily on their own. If it would happen to blow out.
So if there is a fuse in-line, cool, then it worked as intended, but maybe it a tad to small. If not, bejeezus, that keyboard is fragile, or there was something that packed a real punch in that docking station for some reason or another.