Samsung smart led tv came in with backlight problem now fixed.
Blank half screen or dark half screen …This might be backlight strip of one side, check all the led trip and by testing each with digital meter or backlight tester. Again check the voltage of each rectifier diodes of inverter section. below photo has the real sample and and behaviors
2 After removing the tv cover I may see all parts eg. Main board , power board . NOTES. Inverter board is combined in power board so there not separated, however u can test each circuit independently to establish which section is failing . lets do some introduction of above related issues of tvs.. blank picture or no backlight but sound ok. this may backlight problem or led driver failure. When u power up tv the power board generate standbys volts 5volts or 3.3volts depending on designer topology, the standby well be feed to main CPU or main processor and it will release dc volts to power up led power on, you will be pressing power on button by using remote or tv keys this is now to turn on tv .. The power supply will produce 5volts which will be standby then again 24 or 12 dc volts to inverter board. The main board will now be generating on off command to turn on the fully power supply ….
Now when the tv cover was removed I did some testing by checking all the components and found everything ok, I also did voltages test in inverter section and there were almost 140dc volts which means all were working well. I opened everything and removed LCD screen and I were able to reach to led backlights it were two strips, one strip had a burnt mark which indicates things were not good at all on led strips backlight . all two strips replaced and turn on tv I could see good images with fully backlight on tv screen.
Check after screen removed, see where two led strips are inserted. Notes. Be careful when u are dealing with LCD screen panel because u may break it if u don’t concentrates on it , the screen is very expensive so you should be keen to avoid to break it.
Above are two faults led strips and they are replaced with a new one . But sorry I forgot to take
the photos of a new led backlight due to customer speeding up me, she wanted it to fixed very fast so that she take off.
Conclusion the trouble shooting of any electronics equipment is easy but also tough at particular if
u have no enough experience but to those has experience not tough
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