I just got a KP-46WT510 for free that has a red convergence issue where
the corners of the screen cannot be converged properly
in red. (the upper left and lower right are worst, and only red is
effected)
In the center, say 60% of the picture, the red targets can be moved in both directions, and centered.
The
red targets in the far corners are almost a full width away (below) from the
G/B ones, and do not respond to movement, in either direction.
The odd part was that last night while futzing around trying to get into the service menu (never did get it turned on with the 4-key press combo), when I turned it on normally again, the convergence problem was gone!
I was able to run the normal manual convergence routine and get all the reds lined up. But, after about 5 minutes the reds in the corners again "drooped", as before.
Heat didn't seem to be an issue, as it was running for quite a while before I turned it off and back on again. As far as I can remember, this was the first time it "corrected" itself in the testing I've been doing.
Do these symptoms point to anything in particular? Could it be an IC issue, or is it perhaps a cold solder joint, or some descrete component?
Thanks!
OK, after re-testing it, it does look like a heat issue, as it seems to somewhat consistently work OK when first turned on, and then the red fails after a few
minutes.
It seems that even a fairly short off-period can be enough to get it working
again though.
I'll see of a cooling fan on the IC heat sink helps, and that will at least point to the issue.
Before I start ripping the TV apart, does anyone have any guidance as to how
to get at the boards? Do you need to take off both back panels? (are
the boards at the "bottom" of the set?)
Thanks.