There is a fix, but it's not permanent. Mine's been working for 3 months since I "fixed" it. Admittedly, the last 2 weeks, it's hiccuped 3 times, but a quick tap reset it. It was still cheaper than buying a new one, and when it finally does go, I'll have saved up some for the new one.
I've got a kdl-46v4100 with the same problem. There is a "tab" (a kind of paper thin ribbon cable, sort of) on upper right hand corner of the LCD panel that's failed/developed a short.There are a couple of example videos and descriptions of the fix if you scour Google and youtube. It was a problem across several brands around the same period of time. 2 videos I found for Sonys http://www.youtube.com/watch?v=vCExlSnG4yY
.There are some differences between the models, but what they show about the tab is the same.
You have to disassemble the TV all the way down to the aluminum frame that holds the LCD panel to the florescent light box. And by disassemble, I mean only the plastic housing that covers the back of the TV and the front bezel. There's no need to remove any boards, except for the small IR board and one other little board that are mounted in the bottom of the front bezel. Oh, and be careful with the board with the row of buttons on the top of the TV. Don't break the connector unhooking it.
Anyways, removing the aluminum frame will expose the tabs which connect to the boards that then connect to the T-Con board. The temporary fix is to use a non-conductive material to apply pressure on that right corner tab. I used a 2 or 3" long 1" thick strip of foam that I attached to the aluminum frame. When you screw the frame back on, it sandwiches the foam or other material you've used onto the tab, maintaining the pressure on the tab and closing the short. On my tab, the affected area was closer towards the LCD panel where the tab dipped, like in the above video.
You have to be careful unplugging the speakers because they have little catches on the connectors that you have to release. You have to be careful with the connections for the IR board and another little board (forget what it does now). You don't have to remove any of the boards or braces though it makes it heavy and awkward to manhandle by yourself. But, you kind of need the braces so you don't twist the screen and you can lay the monitor on them to test and play with the tab. You do have to brace the left side video port board, when you lay the LCD down to test. The front bezel was more my not thinking it through. I should have put it on first then moved the TV when I put it back together..
Anyways, give it a shot if you haven't gotten rid of it yet and want a secondary display.