My neighbour was throwing out this TV, he said the sound didn't work but the picture was fine. Now I'm turning it on, the green LED on the front flashes a few times, the backlight comes on (still a black screen) the LED continues to flash, then it goes solid about 20-30 seconds. I've taken the back off, no sign of dodgy capacitors, so rather than just broken sound, I also have no picture, also I'm not sure the remote works. On the main board there is an LED at the top with 3.3v written above it, it is flashing very very quickly, it also looks like the PCB is burnt a bit around it. On the right hand side of the PCB there are two other LEDs (one green, one red/green), they flash differently depending on the buttons which are pressed (input/menu etc) on the front pannel. Any ideas? It was about -10C on the day he put it on the curb and it was out there for an hour or so before I got to it, but it wasn't physically damaged. I've got my multimeter ready, but I'm not sure what to test.
SOURCE: works fine for 10-15 minutes, then screen goes
It can be caused by unstable DC in the power supply due to bad DC filter caps, that will be the first place to look. I have a feeling that it may be the main board. Basic LCD monitor and TV troubleshooting guide: Learn about bad caps: http://en.wikipedia.org/wiki/Capacitor_plague Capacitors kit: http://lcdalternatives.auctivacommerce.com/ he can make you a set of caps for you. Or www.digikey.com just make sure to use caps with low ESR, 105c, high ripple current, long life rating such as PANASONIC FM or FC series.
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http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting
http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
http://www.fixya.com/support/r7406380-tv_training_manuals
Failed TV and Monitors: http://s807.photobucket.com/albums/yy352/budm/
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SOURCE: Turn tv on. green light solid display, no picture or sound
The flashing green light is likely indicative of a self-test failure, indicating the TV has detected some sort of internal fault. With no picture or sound, one strong suspect is the power supply. Flat-panel TV's have an internal DC power supply that converts the inbound AC current, and when these fail, or are unable to supply a minimum level of power to the set, it can behave as you describe, providing only enough power for the green light to illuminate.
main board fubar
Testimonial: "Thanks! Replacing the Main board fixed the issue."
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