Ugh..TV just lost picture

[ARCHIVED THREAD] - Ugh..TV just lost picture

Posted: 5/25/2015 10:02:26 AM EDT

48" Toshiba LCD...was watching TV, changed channel and picture went blank, cant get anything on the screen. When I turn it off and back on, itll have a faint whitish look (for about a mila second and then go blank. I got it at Best Buy, its about a couple years old. Im sure its a 10cent diode or something but any ideas?

Posted: 5/25/2015 10:33:56 AM EDT

[#1]

adult programing is bad for the screen

Posted: 5/25/2015 11:07:57 AM EDT

[#2]

Posted: 5/25/2015 11:39:34 AM EDT

[#3]

Thanks to Youtube. Ive determined its the LED driver Board...now im not having any luck finding one.

I did the flashlight test and my picture is there, just not backlight.

Posted: 5/25/2015 12:02:23 PM EDT

[#4]

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Thanks to Youtube. Ive determined its the LED driver Board...now im not having any luck finding one.

I did the flashlight test and my picture is there, just not backlight.

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Find a fix for it? My SIL rebuild my tv with new capacitors. Give me the model and I will look too.

Posted: 5/25/2015 12:19:06 PM EDT

[#5]

Quote History

Quoted:
Find a fix for it? My SIL rebuild my tv with new capacitors. Give me the model and I will look too.

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Quoted:

Quoted:
Thanks to Youtube. Ive determined its the LED driver Board...now im not having any luck finding one.

I did the flashlight test and my picture is there, just not backlight.

Find a fix for it? My SIL rebuild my tv with new capacitors. Give me the model and I will look too.

Yea, its the LED driver board, if I shine a flashlight directly on the screen, I can see everything, and all the menu and volume works, just no backlighting.

Model 50L1350U

I cant find that part anywhere. Sadly its a 40-50 dollar part and take me about 10 min to fix.

Posted: 5/25/2015 12:35:00 PM EDT

[#6]

Seems to be no place. can you pull the back and look at the capacitors? Most of what I am seeing have about 7 caps .

Posted: 5/25/2015 12:38:05 PM EDT

[#7]

http://www.shopjimmy.com/tvs

Posted: 5/25/2015 12:38:09 PM EDT

[#8]

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Seems to be no place. can you pull the back and look at the capacitors? Most of what I am seeing have about 7 caps .

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Yea about ready to do that now.....i cant possibly do anymore harm, lol

Posted: 5/25/2015 12:51:34 PM EDT

[#9]

Worst case find the part numbers and look for cross reference on Shop Jimmy.

Posted: 5/25/2015 1:16:31 PM EDT

[#10]

YEa. well I have 3 main parts and im trying to figure out exactly which has the LED driver.

Posted: 5/25/2015 1:48:03 PM EDT

[#11]

Get a closeup of the top right board, the light tan one. Look for any caps with bulged tops, or sometimes bottom if they don't have pressure relief cuts on top. The wires going up the right hand side of the photo should lead to the LED back light.

Posted: 5/25/2015 1:51:24 PM EDT

[#12]

Quote History

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Get a closeup of the top right board, the light tan one. Look for any caps with bulged tops, or sometimes bottom if they don't have pressure relief cuts on top. The wires going up the right hand side of the photo should lead to the LED back light.

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Ok,,ive pulled the board and hit it with a flashlight, I dont see anything going on. I was wondering what that Black wire going to the top right was.

I figured out that the small board to the left is the LED Driver Board. I know the tan is the powering board and the green at the bottom is probably the "brain"

Posted: 5/25/2015 1:55:43 PM EDT

[#13]

Ive pulled all 3 boards and have looked at them on both sides, I cant see anything obvious. I wonder if the LEDs themselve burnt out, be weird all of them to do that.

Posted: 5/25/2015 2:12:54 PM EDT

[#14]

http://www.badcaps.net/forum/showthread.php?t=42874

Well I followed this procedure and I got 78v dc on the two + pins. so I have power coming to the LEDs.

I dug deeper into this thing, the LEDs all work. I can actually see them. When I turn power on/off, they flash for a millisecond. For some reason they simply arent staying on, so they arent burnt out. Something is shutting the power off to them. Im guessing its the Tan board.

Posted: 5/25/2015 3:12:10 PM EDT

[#15]

Quote History

Quoted:
Worst case find the part numbers and look for cross reference on Shop Jimmy.

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yea they just emailed me back, no go.

I found one on Amazon, its used but dont have much choice.

Posted: 5/25/2015 3:37:09 PM EDT

[#16]

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yea they just emailed me back, no go.

I found one on Amazon, its used but dont have much choice.

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Quote History

Quoted:

Quoted:

Worst case find the part numbers and look for cross reference on Shop Jimmy.

yea they just emailed me back, no go.

I found one on Amazon, its used but dont have much choice.

Sorry I got nothing else.

Posted: 5/25/2015 3:47:31 PM EDT

[#17]

Well amazon has one and another place has one..

What has me confused is that I get constant DC V at the power board connection, the cord and LED connection is buried deep inside. I want to think its the board but with having constant power, i just dont know.

Posted: 5/25/2015 4:08:19 PM EDT

[#18]

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Well amazon has one and another place has one..

What has me confused is that I get constant DC V at the power board connection, the cord and LED connection is buried deep inside. I want to think its the board but with having constant power, i just dont know.

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Switching is probably done on the negative side.

Posted: 5/25/2015 4:20:43 PM EDT

[#19]

Yea that gets above my experience, I just checked for DC V on the neg side, got nothing. What is interesting, I put the problem on the + pin, it was reading 20 DC V with TV off, I turned it on, it jumps up to 140 DC V and then settles down to 76 DC V, did it every time. I have no idea if it means anything, lol.

Posted: 5/26/2015 3:14:37 AM EDT

[#20]

I've had two or three monitors now that had bad caps with no visible signs. If you already have a soldering iron and can pick up the caps cheap, replace all the largest vertical caps on the board. If you don't have a place close by, and I have the right values I'll send you the caps you need.

Posted: 5/29/2015 2:09:09 PM EDT

[#21]

Well it wasnt the power board. I cant keep ordering parts and hope they fix it. May just take this one as a loss.

I know ppl with different brand TVs that last 3x longer and they leave them on all the time, etc. No more Toshiba for me. Junk as far as I am concerned.

Posted: 5/29/2015 8:58:50 PM EDT

[#22]

Sorry it was not the fix.

[ARCHIVED THREAD] - Ugh..TV just lost picture

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