Pentax camera screen is black will not take a picture.

SOURCE: My pentax option A10 turned black on the screen and won't open

Since the screen went black BEFORE the lens retracted, it makes me think this is a main board problem. The only other possibility is that it is the lens assembly, but since it went black BEFORE the lens retracted, I don't think that is it. I can replace the main board for $40, or you can send it to pentax in Arizona, and they will do it for about $90.
The main board is NOT something that I would suggest anyone try to replace as a DIY project. There are too many small screws, and delicate connections to deal with.
You can contact me at: mrfixitmark at comast dot net

If you just want to sell the camera as-is, I also buy all pentax a10, a20, a30, a40 cameras, in any condition.

SOURCE: I have wo black bands across the screen on my Pentax Option 550

have you tried changing the camera's settings back to default? in the camera's menu, find 'reset settings' or 'factory settings' or something like that to reset the camera settings.. you might have messed with some settings, otherwise it may be hardware failure, may be the LCD of your camera.. hope not so.. lol