I suspect the same answer as http://reviews.cnet.com/5208-7593-0.html?forumID=58&threadID=47979&messageID=570995
Are you willing to open it up and look for any "connectors" to wiggle and then put it back together? I "saved" my Canon Digital Elph from an untimely end by doing that. Connectors are usually where such things fail.
In closing, if you used it as a web cam, it could have expired.
Bob
I have a sony cybershot DSC-P31. I have it for a little over a year. All of a sudden the lcd sceen is black. It will show the pictures on the memory stick, but nothing else. Does anyone know what the problem is? There is no lens cap on this type of camera.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic