Samsung LN46C630 Turning on and off....


Standard Member
Hi all. New guy here to the forum, but not to home audio/video equipment.

As the title says, I have a 2010 model Samsung LN46C630K1F that started cycling the power last week, but differently than the clicking sound of the issue Samsung had on the pre-2009 models. It has no clicking sound but rather actually starts up, shows whatever's playing and then drops out. Sounds the little chime it plays, and starts back up only to do it again.

I pulled the power supply board and the caps were in good shape. I replaced them anyway and upped the voltage from 25 to 35 and from 10 to 16 while staying at the same 1000uF rating. I did not however change the 2 smaller 47uF/50V caps but again, they look normal. :confused: Put it all back together, and she worked fine....for about 10 minutes just as before and then started it up again.

And we all know Samsung was no help trying to push me to initiate a service call when all I was asking them was if they had had any new issues reported.

Anybody else seen this issue and if so, what did you do to correct it? I did pickup a PS board and the T-con boards from a cracked display unit for a good price ($115) but still thought I'd post this up here.

Any and all assistance will be greatly appreciated!!
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Standard Member
$125 later, new power supply board, T-con board and LCD convertor board and NOTHING. Same thing. Unplugged the touch sensor board and has been playing for about 4 hours now..... Sucks I changed all that and only needed a $20 part.... Guess that's why I have an e-bay account...


Standard Member
And, maybe not. Installed new PS board, new T-con board and new LCD convertor board. Turned it on and it played for 5 minutes and then started cycling. I unplugged the touch sensor board and as I said above, it played for about 4 hours. Then cycled on and off 1 time. Did it again about an hour later. Tried HDMI2 and it played for about 4 hours and then cycled on and off. Plugged the touch sensor board back in and it played for several hours before doing it a single time on and off. :confused:

Tried the side HDMI and got no sound and a red digital scrambled signal look. I'm thinking maybe the main PC board? Guess I'll search for that now and try it. But why would new everything else allow it to cycle after hours vs. every few seconds???:mad:

Next is a new ultra thin bezel TV...


Standard Member
I almost get the exact problem. This is a model LN40C550. Started on/off and I changed all capacitors (looked all normal, anyway, changed them). Same thing, bought a powerboard online, even worse, wouldn't start,returned it. find a friend with same model, switched the power board, same on/off problem, so it's not power board, update firmware, no use. Mine even doen't have touch buttons on set, only can be contrilled by remote, tried to reach service menu by infor/menu/mute/power no use no service menu appear. Where is touch sensor board?

The funny thing is: if I leave it on, it will on/off for about onehour, then it wil stays on. After that, you can turn on and off, it acts normal. but if I turn it off for 12-24 hours, it will act up on/off again. Now I suspect it's a relay problem or the video board somehow drain too much current make the fault proof software to shut it down


Standard Member
Where is touch sensor board?

It's not "really" a touch sensor but rather a proximity sensor board located on the lower front right corner. The board would be behind the bezel.

Finding replacement boards from damaged units is hard. I can find power supply boards all day long but where are the main board from these "cracked screen" units that keep popping up on eBay and such???

Think I'm going shipping again this weekend as I moved my Samsung 46" DLP back downstairs and going from 1080P back to 720P is not good....

But better than a tube tv.... :eek:


Standard Member
Not yet. I figured with it unplugged, it would work or not. Do you know something I don't? That would be a cheap fix.

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