Sharp LC-52XD1E Large green vertical bands

[badouwes]

Having a large transparent, graded green horizontal band on my Sharp LC-52XD1E TV.



It starts after 2-3 seconds after powering on the TV.

I have made a short video with some explanation of what I have already done, including what happens if I disconnect one of two cables between the TCON board and the LCD panel.

URL: https://goo.gl/photos/ZxTuBXbWFKSuKmQq7

I have already done the following troubleshooting.

- removed dust
- All capacitors on the boards look ok (no bulges/leaks)
- No broken connections/cables
- CCFL lamps/inverters fine (all function, nu flickering)
- I have read the troubeshooting manual on this board
- When disconnecting either of the flat cables between the panel and the TCON board, the band disappears. The first seconds after reconnecting the flat cable the band does not show up.
- As the band is occupying about 3/4 of the height of the screen, I don't suspect any troubles with the horizontal drivers on the panel. I have no vertical bands either, so I have no indications so far the panel is faulty.
- As a result of the above I suspected the TCON board. I replaced it with no avail.

Can anybody help?

Thx in advance! https://www.badcaps.net/forum/images...on_biggrin.gif

[tom66]

Re: Sharp LC-52XD1E Large green vertical bands

Just so you are aware, it is a really bad idea to disconnect/reconnect the panel ribbons while power is on. Permanent damage can be caused to the panel. Not that that matters unfortunately, as this is likely an LCD panel fault. The gate driver for the right hand side has failed, and cannot drive the panel properly.

You may want to attempt a "tab shim", which is a "fix" which involves applying pressure to the appropriate bonds on the panel which have failed. (The problem likely occurs after re-making the connection because the connection has cooled down - once it warms up it breaks the connection.) However I have had poor success myself with this method. Others have had better luck so you might get lucky.

[badouwes]

Re: Sharp LC-52XD1E Large green vertical bands

Tom66, thx for your quick reply. Very much appreciated. And thx also for your words of warning, raising my awareness.

I have understood from troubleshooting guides, issues with vertical/horizontal (gate/source) drivers appear as smaller bands, as normally only one driver (or its bond fails). The band on my tv takes up about 3/4 of the panel. Do you have the experience such wide bands, loose bonds appear overnight over such wide range?

Again, thx in advance!

[tom66]

Re: Sharp LC-52XD1E Large green vertical bands

Yes, I've seen a fault very much like this caused by bad tabs. The problem is the tabs on the left and right - the gate drivers - chain signals to each other. If a connection fails at any one tab, all subsequent tabs will display an issue, too.

[badouwes]

Re: Sharp LC-52XD1E Large green vertical bands

Tom66, clear answer. Thx! I will see what can I do with tabs. Will have to dismantle the front cover and some metal casing.