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Jamie Jamie is offline
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Default Dark strip on LCD...

wrote:

On Sep 8, 5:45 am, JW wrote:

On Wed, 7 Sep 2011 16:02:35 -0500 "Deke" wrote
in Message id: :






"Sparky" wrote in message
al-september.org...

TV is a Polaroid 42" 1080p LCD, model TLX-04244B.
It was purchased on 11/28/08, at Wal-Mart, with an extended warranty.
It has developed a horizontal dark strip, about 3 inches wide, about 1/4
of
the way down on the screen, running from one side of the screen to the
other. A technician from the insurance company is coming to check it out
on
the 13th of this month.
I think one of the backlights has failed. Is it repairable?


TIA!


*Anything* is repairable. Is it economically worth it? Only your insurance
company can tell you. ;-)


It's probably not a backlight. Can you see video in the dark band (look
very
closely -- shine a bright flashlight at the area to help you see)? If the
backlight has failed you should still be able to see video in that dark
band.
If not...


Your LCD display is probably bad. The display is made up of wide bands
(about
3" -- depends on the model) running horizontally and vertically. Each of
those areas is controlled by a driver IC. If one of the driver ICs fail
you
get a dark or light band (horizontal or vertical).


This PDF has some symptoms, causes, and fixes:


http://preher-
tech.com/Documents/LCD%20TV%20Display%20failure%20symptoms%20and%20po ssible*%20
causes.pdf


Yes, video is visible in the dark area, its only about half as bright as the
rest
of the screen. In dark scenes its not noticeable, but on light screens its
easy to see it.


Likely one of the tubes has failed, or possibly the inverter driving the
tube.- Hide quoted text -

- Show quoted text -



What tubes - They stopped using vacuum tubes years ago, the last one
was the CRT itself, and that would not fit the description of an LCD
tv.

Why not? LCD TVs normally have multiples of CCLamps in them and yes, You
would get this effect if one was out.

Jamie