Re: LG 42LG3000 LCD TV Fault Finding.
Here is a question.
Can I swap sides with the Master and Slave to see if the Lamps OK on the left hand side?
--edit
Nope plugs are slightly different. Still looking for ways to test the components on the Slave board then.
DejaVu
Member
Last Activity: 09-29-2013, 01:04 PM
Joined: 09-15-2013
Location: Basildon, Essex
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Last edited by DejaVu; 09-25-2013, 11:01 AM. -
Re: LG 42LG3000 LCD TV Fault Finding.
Nothing obvious that I can see. Looked at the white surface mounted fuse and looks in one piece. Continuity confirmed.
Here's a picture of what it looks like - should be clear enough to make out everything. Clicking it Zooms in.
[url]https://www.dropbox.com/s/feb1j1emfo2t5an/2013-09-23%2019.18.17.jpg[/url]
Here is a YT Video of what I get without plugging in the Slave Invertor Board -
[url]http://www.youtube.com/watch?v=0ayUhUQm0mQ[/url]
Much much better view of the whole board - held...Last edited by DejaVu; 09-24-2013, 03:19 PM.Leave a comment:
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Re: LG 42LG3000 LCD TV Fault Finding.
Major update.
Unplugged the Slave and left the Master in.
Turned on the TV.
Stays on and can see 'The Fly' for a around 3 seconds.
Left hand side (Slave's side) is dark, then goes off.
Think the faulty board has been located!! Can it be diagnosed!?Leave a comment:
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Re: LG 42LG3000 LCD TV Fault Finding.
Looking back on the thread I referenced earlier, I got an idea what exactly you meant and have probed them.
This is what I get back measured using the DMM on 20k Ohms.
Master -
[url]https://www.dropbox.com/s/dex5ce1ba91gwwk/Master.jpg[/url]
Slave -
[url]https://www.dropbox.com/s/9xkzl4i6x32qj0z/Slave.jpg[/url]
Both are the same, so I'm hoping it's right?
Looking at them points close up like that makes them look a right mess!
Re: LG 42LG3000 LCD TV Fault Finding.
...Last edited by DejaVu; 09-24-2013, 01:54 PM.Leave a comment:
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Re: LG 42LG3000 LCD TV Fault Finding.
D'you reckon these need replacing or can they been repaired perhaps?
If not, can I replace them with VT71053.54 & VT71053.55 as they seem to be more widely available.Last edited by DejaVu; 09-24-2013, 04:57 AM.Leave a comment:
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Re: LG 42LG3000 LCD TV Fault Finding.
I'll take some fresh ones. Not sure what happened to the old ones...
Galaxy S3's have a pretty good camera!
Master Invertor Board
[url]https://www.dropbox.com/s/rra4ivv8xxtdxdv/2013-09-23%2019.18.01.jpg[/url]
(I've tested F2 and appears OK)
Slave Invertor Board
[url]https://www.dropbox.com/s/feb1j1emfo2t5an/2013-09-23%2019.18.17.jpg[/url]
(I've tested F200 and appears OK)
VT71053.50 & VT71053.51Re: LG 42LG3000 LCD TV Fault Finding...I'll take some...Last edited by DejaVu; 09-23-2013, 12:25 PM.Leave a comment:
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Re: LG 42LG3000 LCD TV Fault Finding.
Aha, after turning on (and the backlight flickers and the LED goes a faint Blue)
All voltages are as they should be.
Invertor boards are receiving 24.2v.
12v is pushing out 12.3v
5v is pushing out 4.8v
Will check what INV_ON is using, but I'm expecting 24v right?
-edit
Nope. INV_ON is at 4.7v after the backlight flickers.
But on 0v before trying to turn it on (Switch at wall and before Remote Power pressed). So I'm guessing that's correct?
I'd just like to say,...Last edited by DejaVu; 09-23-2013, 10:06 AM.Leave a comment:
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Re: LG 42LG3000 LCD TV Fault Finding.
Great guide and explained a ton!
But this is why I'm getting a little lost because PS_ON and BL_ON doesn't seem to exist on this board.
I *think* I've got it in this picture and I'm guessing it's the ON/OFF (24v?) pin I should be looking at?
Also got something called BRI there too (Somesort of Bridge?)
As well as INV_ON... which is quite obvious now I've thought about it! = BL_ON I guess?
AND Power_On also lives there too!
[url]https://www.dropbox.com/s/6uksajpon0016n0/2013-09-23%2016.06.56.jpg[/url]...Last edited by DejaVu; 09-23-2013, 09:13 AM.Leave a comment:
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Re: LG 42LG3000 LCD TV Fault Finding.
Been checking pins today following this thread [url]https://www.badcaps.net/forum/showthread.php?t=20824[/url] - which has excellent descriptions of what to do and how! Checked the Invertor fuses, both have continuity.
Then I got to the part of '24v to the Invertor boards' and while everything is connected (and in what would be standby mode) I get nothing, nuda, zip. I've checked the 24v on the actual PSU and doesn't seem to be there either.
[url]https://www.badcaps.net/forum/showthread.php?p=241937#post241937[/url]
...Last edited by DejaVu; 09-23-2013, 08:02 AM.Leave a comment:
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Re: LG 42LG3000 LCD TV Fault Finding.
Hunted all round both boards and found this on the PSU. It's about as close as I can find.
[url]https://www.dropbox.com/s/6vw3ehayllhu6q7/2013-09-17%2019.34.41.jpg[/url]
I'm guessing its the third pin from the left at the top marked ON/OFF. Is this the one that would be activate 12v?
I'm thinking I'll have to wrap a small wire around it, replace the connector and test it with the multimeter. This is the same connector that powers the Mainboard and looks to be the only one that does.Re: LG 42LG3000 LCD...Leave a comment:
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Re: Acer Aspire 5520- No power
Try removing the battery, plugging in at the wall with the switch off (if possible), you just need the laptop 'earthed'. Not sure if you have switches on wall plugs in Greece.
Hold the power button for 30 seconds and try turning it on as normal.
Motherboards are notorious for holding static electricity which safe guard then from overloading. Earthing them and opening the circuit (holding the on button) clears the static to ground.Leave a comment:
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Re: LG 42LG3000 LCD TV Fault Finding.
Forgive my n00bness tom66, but how might I go about doing that with this board? I'm guessing you mean this one?
[url]https://www.dropbox.com/sh/1wope3wgily61mh/JIPb_JyU8b#lh:null-2013-09-16%2017.13.15.jpg[/url]
From what I understand, what you're saying is, the mainboard is checked using 5v - perhaps for Standby, if everything checks out and the power button is pressed, the mainboard tells the PSU to fire up the 12v to power the backlight. If the mainboard is failing to tell the PSU (or the PSU is failing to provide...Last edited by DejaVu; 09-16-2013, 05:23 PM.Leave a comment:
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Re: LG 42LG3000 LCD TV Fault Finding.
Just used a multimeter on the PSU outputs of 5v and 12v.
5v reports 5.13v.
12v reports nothing at all.
Seems the PSU is at fault then? Is it worth fault finding and replacing components or better to just replace the board?Leave a comment:
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LG 42LG3000 LCD TV Fault Finding.
Hi Badcaps, great forum, incredibly helpful members and hopefully kind enough to lend a hand with this TV I'm having problems with.
Searched the forum and found similar issues with no definitive answer, so had to create a new thread.
I am new and only repaired a couple of sets in the past, so please go easy and have some patience with me. Thanks.
Took my 42LG3000 apart in the lounge and trying to suss out the faulty board.
Here is a video of the symptoms...
[url]http://www.youtube.com/watch?v=LCWH8EON5j8[/url]
It can't really be seen... -
Re: New Members - please post your introductions here
Hey Badcaps,
Found myself registering here after another fellow forum member recommended this place on another forum.
I've got a LCD TV I'm messing about with for my sons room, which I hope I've already found the fault for by searching this great forum (some amazingly helpful people here btw! Or at least hope your all people, can't be too careful).
I guess I need some clarification that I'm right, but also hope to be of assistance to others with Laptop/PC hardware problems, fault finding...Leave a comment:
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