Hello
I have a 70" Samsung tv. It's a recent 4k model. Produced in 2020. It's barely 3 years old.
At first it was stuck in a boot loop. Something was shorting to the panel itself.
It has a power supply and an integrated t-con with a single ribbon connector to the screen which has three separate small driver boards interconnected by two ribbons.
By process of elimination i deduced the lower right driver panel was the problem.
By either covering a few pins i could get the tv to boot but the image had lines. While messing...
scuby
Member
Last Activity: 06-06-2023, 01:52 PM
Joined: 01-13-2014
Location: den haag
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Samsung 70" 4k "bad panel"
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Re: Bad driver(s)? Sharp LED TV
I'm leaning in a similar direction. Not knowing enough about how these things are put together I suppose I can't rule out the panel although to me I would expect other failure symptoms: half of the panel or a portion or image distortion etc. Not such clean and simple failure.
As soon as the TV is 'playing' anything the blue disappears. That paired with the dimming and trying two t-cons has me leaning towards some sort of chip failure on video processing. I'm hoping so.... -
Re: Bad driver(s)? Sharp LED TV
I'll take your experience over internet speculation...Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
btw. from what I've read about the P8404 connector is that it's a specific power source for 3d. The 12v for the Tcon such run through the LVDS..
Yeah they saved precies pennies avoiding printing on these boards...Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
I'll give that a shot. There's a chip labelled: Pixel works Motion Engine which looks to run to the LVDS. I'll heat that. and observe.
I'll see if I can't find that fuse......Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
Ok. Once the kids are in bed I'll check the LVDS for breaks/continuity.
I'm as sure as I can be that I'm seating that cable correctly. Also since removing it and reseating it the symptoms are all the same as before I touched it....Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
[URL="https://www.youtube.com/watch?v=EsQPTYO5b70"]My walk through of what I've done so far[/URL]Re: Bad driver(s)? Sharp LED TV
[URL="https://www.youtube.com/watch?v=EsQPTYO5b70"]My walk through of what I've done so far[/URL]Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
I can't locate a fuse... looking for a standard cylindrical fuse yes?...Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
Good idea on testing the cable. I will do that tonight. I have not tried any other inputs if not simply because I am not getting a menu or anything.
I'll try the other HDMI inputs. Idea being that perhaps they may show even more of a picture or something?...Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
Hmm. So the Tcon communicates back with the main board? As the dimming is of the LED's.
Here I made a video. Hope that helps gives some clarity as well as maybe spark some more testing ideas.
I can get a mainboard cheap enough in China. Good used for 24 dollars. Takes two weeks to get here. Might just order one up.
It just seems like there is NO video signal getting through.Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
All of the following tests were done with signal input as verified by the audio playing. Not once did any image display.
Along the bottom edge of the TV there are 4 larger white ribbon connectors. Disconnecting the left side connectors result in 1/4th of the screen displaying fully white from top to bottom. Disconnecting the right side the same.
Along the bottom left and right side and in the far left bottom and right corner there are smaller ribbon connectors. The best I could do without fear of damaging something...Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
Unfortunately there is no information on the Tcon board.
I can probe the pins but I'm not going to know what's what obviously.
potential next step?Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
No that test gets me nothing. I posted some pictures. I get one half white, the other half remains black and imageless.
Excellent post if not simply due to being informative and arming me with new things to try. I hate not understanding things. I have a hard time letting it go in that case.
So I think by reading your last post you read mine some more and got some answers however:
I will check the Tcon tomorrow am (1am here in europe now). If/when I find values I'll measure them and report back....Last edited by scuby; 11-28-2019, 05:58 PM.Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
I wash oping you'd replay as to your success the past.
At the end of post two I specify the model number of this set:
The European model designation is: LC-70LE835E
The US model designation is: LC-70E735U
The certified good is unit supplied by a TV repair tech. There's a warranty and I've already contacted him about "new" unit.
It could be at fault though I'm hesitant to chalk it up to it....Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
Ok.
So I threw a new Tcon board at it. Certified good used and working.
Photo 1 shows the "best" result with the original Tcon board.
Photo 2 shows the result with the "new" Tcon board.
It's not consistent. If the Tcon was malfunctioning I'd expect replacing it either to remedy the TV by replacing it. If it's not the Tcon i wouldn't expect it to change anything as it does. If it isn't the Tcon I'd expect the "same" malfunction.
To re-iterate: when disconnecting...Last edited by scuby; 11-28-2019, 12:24 PM.Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
I followed this procedure to reset the set (even though I have no codes).
Unplug set. Hold down Vol - & Input while plugging set back in, release. TV powers up and shows variations of the following image (see attachments). A partial blue screen. Which can hold, flash off for a second and back on. I can't get any menu or other image to show.
After the reset I cannot see a "K" as suggested by some posts.
Hope this helps narrow things down. I can get a Tcon locally quickly relatively cheaply. Is it...Last edited by scuby; 11-26-2019, 08:28 PM.Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
allright: here's wat I've done:
I have 4 cable/ribbons running from the Tcon to the panel. My backlights always come on every time I power up the set. I have no codes flashing at any time.
I have a source playing verified by it's audio.
Unplug the right most cable/ribbon: corresponding half of screen lights up mostly white/grey but lot's of colored lines. See Pic 1
Unplug the second cable from right: corresponding half of screen goes completely white. See Pic 3
Same is true...Last edited by scuby; 11-26-2019, 07:29 PM.Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
Ok. I need a clear guide on that test. Could be me but I'm not reading a consistent methodology.
Give it a signal: verified by audio
Remove outer Tcon cable (I have four). That half should go white?
Reconnect and remove opposite and that half should go white?
Don't need to remove the inner cables?
My backlight always comes on. I have no codes flashing.
thanks...Leave a comment:
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Re: Bad driver(s)? Sharp LED TV
basically my train of thought too
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Re: Bad driver(s)? Sharp LED TV
cheers.
The LE's are the wost offenders in what way? I'm reading a bunch of symptoms/solutions. Worst offenders in panel failure?
Seems so strange to me that the panels fail one moment to the next. I have no codes. I'm still not clear on the Tcon ribbon unplug test that proves a faulty panel (and why/how). Any insight?
Thanks for the help folks. Much apreceated....Leave a comment:
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