My TV had soon, no picture, but backlight on.
The connection of the 12V line on the input board, comming in from the supply board and going to the display controller board was gone. I soldered a wire from some spot close to the incoming connector to the outgoing connector. Tried to upload nice pics, but this unfortunatly did not work, Rgds Hans Driessen, Netherlands
Well, we need to narrow it down to find out if it is the T-CON board, main board, power supply, or backlights inverter board.
First, look at the screen in darkened room to see if you can see any slight glow from the screen, if it does, then the problem can be the T-CON (not getting the 12vdc) or the main logic board not feeding the signals to the T-CON board.
if not, next place to check will be the power supply module, make sure it has 24vdc which is required by the backlight inverter to work, the reason for not having 24vdc can be from bad DC filter caps (leaking/bulging top, high ESR) or short circuits in the inverter board which will cause the 24vdc supply to go into shutdown mode, so you may have to disconnect the power cable that feed the inverter board to see if the 24vdc will work without the inverter board hookup, you will need to apply about 3~4 amp of load to the 24vdc to make sure it can handle that. There are fuses on the backlight inverter boards also. So there is some troubleshooting you will have to do to find out the causes of the problem you are having.
If you are going to DIY and have proper tools, electronics knowledge, and know safety precaution then please read on:
Basic LCD monitor and TV troubleshooting guide:
http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting
http://www.fixya.com/support/r7406380-tv_training_manuals
Failed TV and Monitors pictures: http://s807.photobucket.com/albums/yy352/budm
Learn about bad caps: http://en.wikipedia.org/wiki/Capacitor_plague
Parts: www.shopjimmy.com
Capacitors kit: http://lcdalternatives.auctivacommerce.com/Default.aspx he can make you a set of caps.
Or www.digikey.com, just make sure to use caps with low ESR, 105c, high ripple current and long life rating such as PANASONIC FM or FC series.
SOURCE: screen goes out but sound remains
A blown fuse would not be intermittant.
It is possible that the back plane lamps, and or the back plane power supply is failing.
When the set is in the dark screen, shine a flashlight on the screen at an offset angle. Look carefully and see if you see the picture images. If so, this proves that the back plane lighting is having a fault condition. If there is no image at all, then there may be a fault condition with one of the drive boards for the picture processing or the screen itself.
Jerry G.
SOURCE: Whenever I turn on the television the screen goes black.
You either lost the 24vdc feeding the backlight inverter circuits or the inverter board went out, look for 24vdc first, look for bad caps with leaking/bulging top.
http://s807.photobucket.com/home/budm/allalbums
http://en.wikipedia.org/wiki/Capacitor_plague
http://www.badcaps.net
SOURCE: Hi, my Sylvania 6626lct
Hi, Check all connection on the back. If all is good, go to a repairman. Good luck
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