Sony KV-X2982U shows no picture but has OSD and sound

[Milsec]

Has anybody seen this problem:

No picture it looks a bit like it's warming up except for two faintly white patches at the top left and right of the screen.
The sound is ok and the OSD works except there is no white (shows as yellow) or blue (shows as black?).

I think the screen brightness may have been a deteriorating slightly before this happened (which was today). Initially on first switch on the picture did come back, but on subsequently this has not been the case.

This set had dry joints/caps around IC500 (Vertical Output). I re-soldered and heated joints around this area and that seemed to cure the problem at the time (2006). (Thanks to the member on this forum who suggested this.)