Re: LG TV sound no picture, boards replaced
1) You can upload the pictures here, no need for hosting site.
2) Is this your board? https://www.shopjimmy.com/lg-cov3444...iver-board.htm
3) You have two LED strings, LED1 + (Anode) , LED1 - (Cathode), LED2 +, LED2- each pin of the LED connector is labeled, so your report does not mean much without the pin names.
4) You need to leave black probe on the chassis, keep red probe on each LED pin one at time then turn on the TV to see how high the Voltage jump up too and settle down to, repeat that on the other 3 LED connector pins.
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Re: LG TV sound no picture, boards replaced
LGs are famous for this.
You have one or more bad LED strips..
It IS repairable, but it's a bear.. The good news, it's only 43" so it's definitely doable..Leave a comment:
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Re: LG TV sound no picture, boards replaced
I have to find a hosting sight for pics. I have done more voltage testing. I believe I was doing the tests improperly before
. When I tested before, I would power the TV "on" then place my VOM meter leads on the connections. This time I have the meter leads on the connection before turning the TV on. My updated results are below:
Sound no picture. Flashlight test shows picture. When TV is turned on, "LG" flashes for a split second, then no picture just sound. Six pin connection from power supply board to LED's shows 19.55V when turned on then quickly drops to .03V. This happens at both LED1 and LED2. With six pin LED connector disconnected, when turned on, shows 15.6V to 26V then quickly drops to .0V the drop happens so fast it is hard to see on the meter.
Does this sound normal if some of the LED's are blown? If it does, I did not know the drop or shut down occurs so fast.
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Re: LG TV sound no picture, boards replaced
So where are the pictures I request? Are you really going to take the panel apart without doing more Voltage testing?Leave a comment:
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Re: LG TV sound no picture, boards replaced
Disconnecting the cable between the power supply and main board is a test for Samsung TVs. Don't think LG's have pullups so doesn't apply.
43" screen isn't that bad for handling since not super big but you need to be careful. You can turn on the TV with the panel disconnected so you can observe the LEDs flash to identify bad strips but best to do a full replacement with new strips and never run the backlight at max.
Not your exact model but close. https://youtu.be/T2FboV-1PJgLast edited by neilc6; 09-25-2019, 12:46 AM.Leave a comment:
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Re: LG TV sound no picture, boards replaced
"Do the backlights turn on for a second then go out"?
"Do the backlights come on with cable from powerboard to mainboard unhooked"?
When you turn TV on, screen flashes "LG" for a split second then nothing (but sound). When you disconnect cable from power board to main board the TV appears not to get any power. The standby light does not come on and no sound.
I think I will have to check the LED strips. Is there a tutorial on proper screen removal? Advice appreciated, I have never done this before. 43" screen, do I need suction cups, or is there another way? Thanks everyone for your help and super fast response!Leave a comment:
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Re: LG TV sound no picture, boards replaced
Do the backlights come on with cable from powerboard to mainboard unhooked? Power cord should be unplugged before removing cable then plug power cord back in to powerboard.Leave a comment:
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Re: LG TV sound no picture, boards replaced
sounds maybe something is fishy with that replacement PSU's backlight driver part. Not convinced on that. There should be power ramping up on the LED connector when you turn the TV on, then voltage should ramp down again. Do the backlights turn on for a second then go out? LED's are current controlled, not voltage controlled.Last edited by CapLeaker; 09-24-2019, 02:16 PM.Leave a comment:
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Re: LG TV sound no picture, boards replaced
Lest see good clear pictures of the whole backside of the TV showing all the board, and then good clear straight shots of the whole top and bottom side of the power supply/LED driver board.Leave a comment:
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Re: LG TV sound no picture, boards replaced
Most novices want to replace the power supply board when there is no backlight or if they flash or flicker. Always confirm the backlights are good by watching them power up with the panel removed or with a led tester before suspecting the ps. Backlights shutting down is a protection feature and not a failure. If they fail open, there will be no flash.
https://www.badcaps.net/forum/showthread.php?t=79561Last edited by neilc6; 09-24-2019, 12:49 PM.Leave a comment:
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LG TV sound no picture, boards replaced
Would greatly appreciate any help with my LG flat screen TV
LG 43UJ6200UA.CUSYLH Sound no picture. Flashlight test shows picture. Replaced power/LED driver board and main board. Same thing, sound, no picture. Six pin connection from power supply board to LED's shows .02 volts and .03 volts connected, and .02 volts and .03 volts with LED leads disconnected.
If LED's are blown, shouldn't new power boards LED connections have power with LED leads disconnected? Does this power/driver board not put out voltage to the LED's unless there is a draw? No support from new boards provider.
At the 14 pin connector on the power board, I have 11.8 volts at the five + marked connections when the TV is on standby. When the TV is "on" I have 3.45V at the PO connection, and 3.22V at the PDIM, and INVON connections. Wires and connectors between power and main board are good. I have not checked the LED strips yet. Trying to avoid removing screen to do so.
This TV only has one power board and one main board. There is no separate inverter/LED driver board or TCON board.
Thank you for any help or guidance
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Hi, this is my personal laptop, which the original board (lets call it Board A) blew up PU8700 (TPS51486), making a hole on the board, i had left the laptop at my desk one day with the battery fully charged and didn't touch it for a week, but when i tried to turn it on it didn't
Thought the battery was dead, so i plugged in the charger then tried to power on, the power LED blinked once, charged LED still orange, unplugged the charger, plugged in again and I noticed the "magic smoke" smell, so i unplugged the charger, removed the back cover and saw the blown IC (the "magic... -
Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.
Upon bringing it home and plugging it up, it showed a standby light.
I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.
The screen seems to blackout and stay black, but with a flashlight I can see the display.
With my Playstation 4 connected via HDMI, and running a game I can hear sound.
Assuming... -
Hi All,
Need help.
I have a samsung un60j620dafxza led tv. When I plug it in it has no display, no sounds, and no standby lights.
So I opened the tv and disconnected the power to the mainboard and the backlight powered up. This according to many people says that this is a mainboard
problem. I checked the voltage coming from the stb and I read 1.3 volts on pins 1,3,5 and 7 which are low volts instead of 13 volts which i think the lcd panel
might be drawing too much power from the power supply that it prevents the right voltage going to the mainboard.... -
Hello all, I was given a 55" 2017 TCL Roku TV that has an issue of no picture, but the backlights and audio are in full operation. I did some digging and narrowed it down to a possibly bad T-Con board, I replaced it today with a unit I got off of Ebay but the issue is still there. I'm not good with electronic testing (multimeter, soldering, etc.) so I would appreciate any insight on the likely cause. Screen appears undamaged and the remote can still switch around settings (I've tried a hard reset). I assume it could be the video or power boards, but I also had a theory on it being the ribbon... -
Hi all!
I've recently run into an issue with my Samsung UN55H8000AF LED TV displaying no image. I've done quite a bit of research in terms of what could be wrong with it. Below are the steps I've taken prior to reaching out here for some assistance:
1. I've tried replacing the T-Con board (BN95-01594A), twice and have still experienced the same issue with all the boards I've tested with.
2. I've tried to remove one side of the ribbon cable that goes from the T-Con board to the panel and still not getting any image on left or right side.
3. I've checked voltages...
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