Sharp LC-40LE510E Green color only

[Andreasbest]

Hello.
I have a LC-40LE510E that displays only green color and if left on same channel for some seconds then it fades out until black, when i change channel it gets bright green then fades again and so on.
I have taken photos of all boards and symptoms but since that seems mostly like a T-Con issue i taken lots photos of it.
Unfortunately the service manual isn't available to public so i count on your experience

[tom66]

Re: Sharp LC-40LE510E Green color only

Looks like a defective LCD panel.
This TV is made by VESTEL not Sharp, it is just re-badged and is absolute junk.
Maybe try checking panel voltages on T-con board, non replaceable part.

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

Looks like a defective LCD panel.
This TV is made by VESTEL not Sharp, it is just re-badged and is absolute junk.
Maybe try checking panel voltages on T-con board, non replaceable part.

Damn... Do you have any idea where should i measure and what voltages should i expect ?

[tom66]

Re: Sharp LC-40LE510E Green color only

VGH = about 20 to 30V
VGL = about -5V to -10V
AVDD/VDD = about 14V to 16V

those are the key ones, all measured with chassis ground as negative.

[mmartell]

Re: Sharp LC-40LE510E Green color only

Hay tom i have a 42 Inch plasma i got a main board from a 50 Inch tv both Samsung same part number the pic is not cenered

Can u help mr tom trying to fix tv for granpa

Are you serious right now ?

Stop crapping here or at least find a thread that's similar to your problem or create your own thread.

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

VGH = about 20 to 30V
VGL = about -5V to -10V
AVDD/VDD = about 14V to 16V

those are the key ones, all measured with chassis ground as negative.

Ok i'll take the measurments on Monday that i'll return, meanhwhile can you please explain me in which way can a lcd panel get defect?
I mean it doesn't contain any pcb or any components, so how the glass and the printed lines on it can get defect and display only green like in our situation?
I'm a noob on lcd repair, so please excuse any foolish questions i might ask

[tom66]

Re: Sharp LC-40LE510E Green color only

There are chips bonded to the panel on those little orange ribbons. 99% of the time they are what fails. Exactly why, I don't know, they seem particularly predisposed to do it.

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

There are chips bonded to the panel on those little orange ribbons. 99% of the time they are what fails. Exactly why, I don't know, they seem particularly predisposed to do it.

Whoa, didn't knew there were more components after the T-Con board.
Do you have any photo to get any idea of what we are talking about?

[tom66]

Re: Sharp LC-40LE510E Green color only

None myself but any time you take apart a cracked LCD have a look at the chips. On the newer panels there are only a few, so they seem to fail more often due to too much heat. They control the columns of the display (SOURCE driver.) Sometimes there are external GATE drivers for the rows, other times these are built into the panel itself. Lead free solder bonding underneath them might be a failure point, but I have tried reflow with no success.

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

I see. So perhaps the green color on my LED tv is indeed a faulty panel, i wish not

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

VGH = about 20 to 30V
VGL = about -5V to -10V
AVDD/VDD = about 14V to 16V

those are the key ones, all measured with chassis ground as negative.

Finally managed to get the manual for free.
I'll check the measurments you suggested and the manual later that i'll return to the bench.
Meanwhile keep the service manual for the records, it's very rare for free.

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

VGH = about 20 to 30V
VGL = about -5V to -10V
AVDD/VDD = about 14V to 16V

those are the key ones, all measured with chassis ground as negative.

Ok i'm on the set now, i checked the t-con but i can't found any VGL or VGH , although i can found VGL_L and VGL_H, also no AVDD/VDD.
Can you please point me out?

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

Anyone out there to point me the test points on pcb pictures???

[tom66]

Re: Sharp LC-40LE510E Green color only

Try VONE and VOFFE if you can find them, as well as VGL_L and VGL_H.

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

Ok, replying in a while.

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

VGL_H = 7,81 and VGL_L = 0.5v (suspicious)
No VONE or VOFFE test points as i see.

[tom66]

Re: Sharp LC-40LE510E Green color only

I can see at least one point marked VONE_28V and one marked VOFFE_7.5V or similar.

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

Hello again.
Sorry for the huge delay but i left this tv set on the side for a while to complete some more urgent work.
Now i have plenty of free time and i catch it again, so the voltage on VONE_28V is 31v and on VOFF_-11V is -11v seems everything is fine on those 2 checkpoints.

[Andreasbest]

Re: Sharp LC-40LE510E Green color only

Plus i got 2 great news, i completely disassembled the panel and found 2 very promising facts.
1) The panel is not Vestel , it's Samsung.
2) The panel it self doesn't have any components on it only the printed lines, so i think the panel cannot be defected. I attach a photo too.

[mmartell]

Re: Sharp LC-40LE510E Green color only

That WOULD be great news if Samsung did not have an abysmal panel failure rate too as evidenced by the empirical data in this forum.