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Thanks for the contribution Franki Lobaina
The output voltage of the backlight oscillates and it is not constant, which means that there is something wrong with the output section of the backlight voltage between 10v -18-35-49-127 and remains in a loop
Queries
1- The source fault can be repaired
2- Which components should I check if it is possible to mark them in the photos I uploaded
3- In Ml the Source Module $ 1,800 is used Lg 49lf6450 will it be a good idea to buy it used in the case that it cannot be repaired?
Thanks in advance
Friend in my little knowledge I think that buying another card is in vain, it will follow the same problem, the voltage is western because you have leaking or open LEDs, instead of buying a card buy all the new LED strips so that you solve the trouble. As I understand all LG TV models (lf and lb) bring 6 volt 2 watt led. You can verify this voltage of the LEDs with which they are still good. The decision is yours. Greetings and luck
Hi Riveram26 Thank you for your help I pass you the measurements I made, this time taking the negative to negative measurements of the LED power and not to the TV chassis
Test of the output of the power supply to the LEDs with the LEDs disconnected apparently the fault is in the source in the power part of the backlight
I uploaded a video to appreciate the flaw in my YouTube channel
https://youtu.be/_oGdjutH97E
Greetings and thanks in advance
Hi Javier, I saw your video, but I really can't appreciate the tests you're doing just by looking at the tester. You tried to measure the LEDs one by one to see what value you get is a good way to chueqear the status of the LEDs, tell me how you keep doing. Regards.
Hi Riveram, 26 the test I carried out is to measure the voltage that goes to the LEDs, with them disconnected because I suspect that the source is bad and obviously it is since the Voltage falls and oscillates
backlight voltage varies between 10v -18-35-49-127 and is in a loop
Queries
1- The source fault can be repaired
2- Which components should I check if it is possible to mark them in the photos I uploaded
I send you an image of the output where I made the measurements
http://img18114.imagevenue.com/img.php?image=713969578_Testfuente_122_727lo.jpg
I await your response Thank you in advance
The fact that the voltage is very high or unstable does not assure you that the problem is if or if in the backlight controller, that could also be due to short or open LEDs, look I leave you the link of a video of a colleague very good that could guide you more in your repair answer your questions is all very well explained in its channel there is much more information regarding failures like these. The sector to which you should work if it were the source is the back but in the same video you can realize.
https://www.youtube.com/watch?v=q0J3z-dioLQ
Thank you very much for your help Riveram26 and Franki Lobaina solve Part of the problem since I changed the power strip that was short, but In my opinion the source is wrong since the voltage drops and oscillates and what is that switching source in complexity escapes my Current knowledge and I can not devote much more time I have to work on my other repairs so I reached a point where I find it convenient to refer it to a specialized LG service since they have the tools to check the LEDs without disassembling the entire TV
Javier, it is a pleasure for me because apart from being my work, electronics is my passion and it is a pleasure to share knowledge with people who value and thank them, there are still selfish or malicious people who give you intentionally wrong information but good for that. We are happy greetings and success in your future repairs.
The fact that the voltage is very high or unstable does not assure you that the problem is if or if in the backlight controller, that could also be due to short or open LEDs, look I leave you the link of a video of a colleague very good that could guide you more in your repair answer your questions is all very well explained in its channel there is much more information regarding failures like these. The sector to which you should work if it were the source is the back but in the same video you can realize.
https://www.youtube.com/watch?v=q0J3z-dioLQ
