Laptop screen flashes, locks itself

[Jess]

This problem has been having for maybe over a week. Whenever I adjust my laptop in certain positions (I have my laptop on my lap, and I'm sitting in bed, if that makes any difference), the screen flashes black. Sometimes it flashes a few times, it goes back to normal, or it stays black and the computer locks itself and I have to type in the password to unlock it. I don't know what is going on and why it's happening. It's like something on the bottom of the laptop is causing this, but I have no clue as to what. Does anyone have any idea of the problem?

[Darkness.]

It sounds like the cable connecting the LCD screen to the motherboard has come loose. Have you dropped or done something to the laptop recently that might cause this? The locking issue might be caused by the laptop thinking that the lid is closed because the screen is off.

[HunterSteele]

It sounds like the sensor which detects when the screen is closed is broken and is indicating the screen is closed when it's not. If your computer is still under warranty it can be fixed. If not, you'll have to deal with the inconvenience.