This happened randomly after a month of having this thing as well (This laptop is horrible by the way), but this time i was using it and my ferret jumped on the keyboard and the screen got dim, and of course same as before, the brightness adjuster did nothing to brighten it.
Last time i just took it in since i still had 1 month warranty, but this time i wanted to see if there was a way i personally could fix this without having to take it in? I've noticed other people have had the same problem, and i did the exact same thing they did to fix it, but still nothing happened.
Any idea what this is and how to fix it? This is my laptop for work and i really need this fixed soon. Hope to hear something that works!