My Samsung LCD, LE37A557, has been working fine since 2008 when I got it. Until one day, when suddenly while watching a program, the picture dimmed quite noticeably. I mean, like if I had turned down the brightness setting all the way down. It affects the whole screen uniformly, including the menus.
Doesn't matter what input source I use so it's not a signal problem.
The only way I can get a watchable picture is by cranking the brightness setting up to 100 (it was usually plenty bright around 45). It gets pretty washed-out, even with contrast at maximum. In daylight conditions, even full brightness is not bright enough to watch.
The backlight turns on fine, as I can witness through the rear vents.
First I figured that maybe the backlight CCFLs are dimming due to age, but, it seems like that would be something that would happen gradually and not suddenly. I notice no dark band across the screen, so I figure it's probably not a single dead CCFL.
Noticing a bulging capacitor on the power board, I ordered replacement capacitors and replaced all the ones I could find. No improvement, unfortunately.
Next, I replaced the CCFL inverter board with a spare part I bought online. Made no difference as far as I can tell.
Do you know what part I should looking at next?
I gather that either
- Main board could be sending a bad signal
- T-con board could be messing up the brightness somehow
- LCD Panel has given up
- Backlight inverter board or power supply board could be producing too little power to run backlight CCFLs at full brightness (but I more or less eliminated these already, I think)
Can the T-con really affect the brightness? All the errors I can find related to it all look like weird artifacts on screen, of which I have none.