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info tech
info tech, Technician
Category: TV
Satisfied Customers: 15785
Experience:  Television Engineer for many high street outlets 20 plus years experience
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My LG LCD TV broke down. While watching TV, it suddenly turned itself on and off 5-6 t

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Hi! My LG LCD TV broke down. While watching TV, it suddenly turned itself on and off 5-6 times and then went dark. When I switch on the TV, it makes a long beep, but the panel stays dark. Is it something that can be repaired at home? I have some knoledge of basic electronics.
Hello, and sorry you're having problems. We are now connected on this website- which saves you money over having a Tech come to your home, and in many cases we can fix the problem you're having. In other cases, these things do require additional parts to fix. But I can help you with that as well. In order to help you, I need to ask for more information. 1) Does the set still have normal audio from the programming? 2) Is the power light in the ON status- but simply a dark screen?
Customer: replied 2 years ago.
1) No audio
2) Power light is on, but the screen is dark
Please grab a flashlight and darken the room. Shine the flashlight directly at a 45 degree angle to the screen, and press MENU on the TV itself. Can you barely make out a shadowy image of the MENU?
Customer: replied 2 years ago.
No. I can't see anything, it's completly dark.
Okay, then there's not a one shot diagnosis on what's causing this. It's either your Power Board or your Mainboard- either will give you the same symptoms. You will need to pull the back off the set, and use a Digital Multi-Meter and be able to measure voltages inside of the TV to narrow this down further. Do you have a meter and is this within your comfort/skill level?
Customer: replied 2 years ago.
I can use the multimeter, but unfortunately I do not have it with me at the moment. We have to postpone this until tomorrow then.
Okay I will not be around tomorrow so I will opt out.
Customer: replied 2 years ago.
OK, thank you for trying to help me!
HelloWelcome My name is ***** ***** diff expert I will be happy to help once you get a meter thanks please let meknow when you have it by coming here Anthony
Customer: replied 2 years ago.
I have the multimeter now and I have removed the rear cover of the TV.
OK look at the power-board there will be a plug and socket on the board with leads that go off into the panel ,this is the supply for the LEDs it will consisit of a negative and positive voltage let me know when you spot that if you do not see it please post me a pic of the powerboard using the paperclip Anthony
Customer: replied 2 years ago.
Yes I see those sockets, there are 2 of them.
OK they should be labelled with two voltages a positive voltage and a negative voltage so its meter set to DC red probe of meter to each in turn black probe to metal chassis
Customer: replied 2 years ago.
Seems like there is no positive voltage. The negative voltage reads 0,11 V.
You will need to replace the power-board, get the part-number found on the board itself usually begins BN and try initially if they do not have it google the partnumber for suppliers Let me know if you need more help Please consider rating the answer positively there will be a rating bar of stars usually at the top of the page with this post thank you, ***** ***** positively enables me to receive credit from the site thanks again, the session will remain open and stay open as long as you need it, if you have any concerns please just let me know and I will answer any queries you have Many Thanks Anthony
info tech, Technician
Category: TV
Satisfied Customers: 15785
Experience: Television Engineer for many high street outlets 20 plus years experience
info tech and 4 other TV Specialists are ready to help you
Customer: replied 2 years ago.
Hi Anthony!
I just have a quick follow up question for you. My TV PSU part number is ***** and I ordered the replacement board, but they sent me EAY60803201 instead. How can I tell if they are interchangeable? I tried it and the panel light turns on for a few seconds, then turns off again. Is it because the new PSU board is faulty or because the part they sent me is incorrect?
Can you tell me what you mean by the panel light?do you mean the back-lights?if so do you get a picture for those few seconds?
Customer: replied 2 years ago.
Yes the back-lights turn on and I see LG logo for a few seconds, then the back-lights turn off again.
I am not sure if the boards are interchangeable please take those voltages again and let me know if they come up Anthony
Customer: replied 2 years ago.
There's 99V on black wire and 38V on red wire.
There should be a positive and negative voltage red lead to the voltage point black lead to chassis so one voltage will have a negative sign on the meter
Customer: replied 2 years ago.
Sorry it's the opposite, 99V on red wire and 38V on black wire.
Customer: replied 2 years ago.
All the voltages are positive.
OK just to clarify is this exactly the same issue as before?
Customer: replied 2 years ago.
WIth the old PSU the backlight did not turn on at all. Now It turns on for 1-2 seconds and then turns off. After that the screen is black just like before.
I think you need to send the board back and get the original part-number in that case....... Anthony
Customer: replied 2 years ago.
But I checked, now I see the image when I shine the flashlight at the screen.
I do not know what you mean by "but I checked"?the backlight is out but you are now getting it up so the issue is different which means you will have to get the correct board
Customer: replied 2 years ago.
OK thanks.
When the situation of the fault changes and a wrong part number is ***** its nealy always because the board is not correct, I see this all the time, boards will lok exactly the same but will not work with certain main boards and panels