I have a backlight issue with a Samsung LN46C630 LCD TV. At first, whenever I changed channels the backlight would start flickering. This would happen when the screen went black and then an image came back on. I also noticed I could get it to stop flickering by changing channels again which would change the screen to black and then back. I noticed that it wasn't just the source that was flickering. When I hit the menu button, that would flicker as well. At this point I figured it was a backlight issue. Over the course of the next few weeks, it become unable to be fixed by changing the channel or source. I then went into the menu to find the backlight control. It was set to a relatively high level (16/20). So I backed it back down to a lower level and the flickering went away. I was able to step the control higher to get a brighter picture as well, but once the screen went to black from either a channel change or switching to commercials, the flickering started again. At this point I lowered the backlight to zero. For the next two weeks or so, this resulted in no issues with the flickering, although the image was much dimmer. But then the flickering started again. I noticed that it was more apt to flicker after the screen had been on for a few hours.
I did some research online (spent some time lurking up here for about a month) and noticed that there had been a lot of capacitor issues with samsung over the past few years. I took the back off and took off the power panel to examine the capacitors on there. I don't see any physical issues with it, and after looking to where the inverter board connects to the power board, I'm really unable to determine where my issue might be coming from. I'm an electrical engineer and have access to tools and parts to fix the boards, but without schematics and any experience with these boards I'm ill prepared to determine the cause of the backlight issue. It looks as though the power board isn't providing enough current to the inverter board.
Thoughts?
Here is a picture of the board. The inverter plugs into the two upper right connectors. The side connector looks like power and the top connector is some sort of control.
I did some research online (spent some time lurking up here for about a month) and noticed that there had been a lot of capacitor issues with samsung over the past few years. I took the back off and took off the power panel to examine the capacitors on there. I don't see any physical issues with it, and after looking to where the inverter board connects to the power board, I'm really unable to determine where my issue might be coming from. I'm an electrical engineer and have access to tools and parts to fix the boards, but without schematics and any experience with these boards I'm ill prepared to determine the cause of the backlight issue. It looks as though the power board isn't providing enough current to the inverter board.
Thoughts?
Here is a picture of the board. The inverter plugs into the two upper right connectors. The side connector looks like power and the top connector is some sort of control.
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