Top half of screen is darker than bottom half

SOURCE: SONY xbr screen problem

It sounds like one of your circuit boards may be going out. I'm sorry I don't have a better response than that.

SOURCE: Dark horizontal lines on Sony KLV-26HG2 LCD TV screen

Hello,

If you can fix it by yourself, there is a problem in horizontal circuit panel, you need to check that in series because the part appear visbly good but when tested by the exact tester you register busted. that should be replaced immediately. Check also the vertical panel parts of the circuit. but if hard you do the job you may consult the service center of your TV or the vendor of the TV.

ps. please don't rate me if you are not convince of my suggestion.

best regards, melnavz

Samir Shah

• 220 Answers
• Posted on Apr 08, 2008

SOURCE: One half of screen sees darker than other

Problems described are related to Backlight.It is possible that backlights of affected area have become weak.
You may need to contact the company for repairs and Yes the Repairs may not be cheap.
Samir

SOURCE: Top half of screen is darker than bottom half

The problem is most likley the TV backlight - it is very unlikley to be the graphics card or video input or any other circuitry within the TV.
Also, the problem can be manifested by flashing or flickering of one or both halves of the screen, and sometimes it is a left/right split rather than a top/bottom split, depending on where the lights are positioned. Before failure, you sometimes hear a very high frequency buzz for a few weeks before it fails - the frequency can't be heard by most adults as it ranges from 15kHz-25kHz, but children\animals can usually hear it.
Generally you will need to replace the backlight tube or the invertor that drives it. Generally you can identify the backlights as thin glass tubes buried deep within the panel itself usually with one wire going to each end of them - they are very fragile. The invertor is connected to the backlight tube and looks like a circuit board, often containing a high voltage warning. Usually there are two or four conductors connecting the invertor to the tubes, which can be identified as thicker individual wires as opposed to the flat ribbon wire used for data for the actual image displayed on the screen.
On some screens you may be able to unplug\swap one or both tubes to identify if it's the tube or inverter.

SOURCE: Sony Bravia LCD half screen is darker shade sometimes

Magnetic fields don't affect lcd screens, unlike crt tvs where a magnet can cause problems. If it is only a slight difference i have seen this before even on my tv. if you go to a blank screen you can see patches of light and dark, they call this bruising, i have talked to sony engineers about this but i have not got a straight answer as to what makes this happen, if the tv is in warranty a tech will replace the panel, if it is not in warranty it is not cost effective to replace. But the good news is that is does not seem to get any worse with time, it is more of a manufacturing defect that most will not notice. Look at the tv with dark blank screen and you may see areas where the screen is lighter than the other. If you see this than you have this issue. it will fade off and will not be a stark line. Also I noticed that there is a software update for your television go to www.sony.com to get a download of the software, or sony will send it to you free of charge.