Lg l204wt

[smason]

This nice looking 20" LG belongs to a family member.
I forget the original symptoms, but it was pretty much dead when I picked it up.

Man what a pain to open up. Once I got the panel out of the plastic case, I notice nothing holds the metal cage that the boards are in, to the panel other than the metal tape.

Initial inspection 2 bloated Samxon 1000 @ 16 caps. I decide to do a total recap (minus the 2 big 450v ones, only because I didn't have 'em)

The power supply/inverter board looks to be decent quality, and there are 4 interesting copper heat sinks on the top that cool 4 transistors on the solder side.
2 of the 1000 @ 16 caps measure 27 and 31 uf and 7 and 9 ohms esr. No surprise it didn't power on. The 1uf and 47uf small caps (startup?) were a bit high esr as well.

After the recap, it fired up, but looked like crap. Colour was awful.
Factory reset helped the focus, but not the colour.
Found colour balance in the menu, and looks perfect now.
Not looking forward to re-assembling it now..

[retiredcaps]

Re: Lg l204wt

Initial inspection 2 bloated Samxon 1000 @ 16 caps.

Samxon GF series?

[smason]

Re: Lg l204wt

Samxon GF series?

Yup!

[Xtoforas]

Re: Lg l204wt

Hey Smason, how did you open the case up?

I have a similar issue (does not power up) and was thinking of trying to replace the caps but had a bit of a tough time trying to pry it open.

[retiredcaps]

Re: Lg l204wt

but had a bit of a tough time trying to pry it open.

https://www.badcaps.net/forum/showpo...84&postcount=2

[Xtoforas]

Re: Lg l204wt

Is the attached screenshot the repaired board or the bad board?

I finally got it open and 2 of the 47uF caps in the bottom left of your picture look somewhat blown. Its not very obvious (to me at least since this is my first time trying to repair blown capacitors) but everything else looks pretty close to the picture you attached, hence the question.

[retiredcaps]

Re: Lg l204wt

Is the attached screenshot the repaired board or the bad board?

The pic that smason has in post #1 is the bad board with bloated caps. Notice the dome?

Also note that smason recapped every cap minus the big ones.

[smason]

Re: Lg l204wt

Sorry, Xtoforas, I didn't see your question till now.

Definitely a pain to open. Easy to work on once the case is apart.

[bebisnet]

Re: Lg l204wt

Just had a fight with one. Real pain to open up!

[UncleVom]

Re: Lg l204wt

Add me to the folks who were struggling with getting this one open until I came here.

Same non-start problem, same Samxon caps.

I replaced the three 1000UF and the two 680UF and now things are back to normal.

It went back together very easily, but I must admit I gave it quite a few tests before I snapped the trim back on, I didn't relish the thought of taking it off twice.

Thanks for this great resource.

[retiredcaps]

Re: Lg l204wt

I replaced the three 1000UF and the two 680UF and now things are back to normal.

I didn't relish the thought of taking it off twice.

You MIGHT be opening it again if you didn't repalce all, but the largest capacitor.

Capacitors die from age, heat, and shoddy build quality. Capacitors DO NOT have to be visibly bloated in order to bad. They can be out of tolerance uF (a 1000uF measures 20uF) and/or have high ESR (ohm). A multimeter will be insufficient to test for ESR. For that you need an ESR tester which costs between $50 and $300.

Most members here will recommend that you replace ALL capacitors with reputable brands from reputable sellers. Brands like Rubycon, Panasonic, Nichicon and United Chemicon are suggested. A list of recommended caps can be found at

https://www.badcaps.net/forum/showthread.php?t=2280

The one exception might be the largest capacitor on the power board which rarely, but not never, fails.

Here is an example of how to choose capacitors with respect to capacitance, voltage, diameter, height, ripple and ESR.

https://www.badcaps.net/forum/showpos...4&postcount=19

[UncleVom]

Re: Lg l204wt

Thanks for the advice.

Maybe a classic case of "If you don't have the time to do it right the first time, when are you going to have the time to do it again?" (-;

So far so good though.

I used Rubycon VL caps for replacement.

The board and situation looked the same as that of the original poster, I will remember to post pictures of my next similar project.

While this was my first posting to this forum, I have had experience in the past working on electronics and have recapped well over a dozen motherboards during the height of the storm a few years ago, at least a couple of which are still in service despite being rather long in the tooth.

[clark422]

Re: Lg l204wt

Please let me know the capacitors location. I have mixed up, I am so stupied .
25V 680uf, 25v 1000uf, 16v 1000uf.

[selldoor]

Re: Lg l204wt

Nothing to smile about then!
Can you post a picture of your board showing the missing caps. It may then be down to sleuthing ,guesswork or good luck unless someone has a board in front of them (even to asking someone selling a board on ebay if they can help!)
Perhaps looking closely at pics and your caps can help eg the cap at C202 has a 25 on it - probably 25v so that is not the 16v cap.- some of the others have 8 or 80 so possible the 680 cap. Are the 680 25v and 1000 25v physically different sizes? etc

[Scenic]

Re: Lg l204wt

Go backwards from the output connector (bottom left in the pic in post #1) to the caps. As in: follow the traces from the labelled pins till you reach the positive pin of where the cap was.

Most likely scenario:
The 5V pins go to 16V caps, most likely through the inductor (the black thing in heatshrink tubing marked "L" on the board)
The 15V pins go to 25V caps

[clark422]

Re: Lg l204wt

I do not know which one is for C202, or C203, c204, c205, c206.

Something 25V 680uf, something 25v 1000uf, 16v 1000uf


Who knows the exact location for these capacitors?

Thanks,

[PlainBill]

Re: Lg l204wt

I do not know which one is for C202, or C203, c204, c205, c206.

Something 25V 680uf, something 25v 1000uf, 16v 1000uf


Who knows the exact location for these capacitors?

Thanks,

LG knows. Selldoor suggested you post pictures so we could figure it out. Since you won't do that, try looking it up yourself in the service manual.

PlainBill

[MadMalloc]

Re: Lg l204wt

how did you open the case up?

Since google finds this thread, I'd like to add some details, though the post is old.
This is based on opening my LG Flatron L204WT-SF (MFG Sept 2006):

1. Remove the round bottom base for easier removeal of the bezel, squeeze the four tabs in the bottom then pull the round base away from the monitor.
2. Turn the monitor upside down, and examine the gap between the bezel (grey plastic on front) and backing black plastic. Locate the convenient "starter gap" below the DVI port (right side when facing the front).
3. Using your separating tool of choice (I used a butter knife without damaging the plastic too much), insert into this "starter gap", prying down on the black backing plastic, and up on the grey bezel. I found that the bezel was much lighter and easier to pop the catches than trying to pry the other way around. Continue prying till you pop all the catches and the bezel comes off.
4. Place the monitor screen-down, and gently lift the black backing plastic off. You'll need to hindge to the left, since the buttons on the back are connected to the main body.
5. Wiggle the connectors on the back button panel till they come off.

All in all, pretty easy.

Now, to find out why mine suddenly died (no power LED, just buzzing).

[Dunbrook]

Re: Lg l204wt

Repairing my LG L204WT-SF monitor, and need to confirm the cap voltages (I am not at the same location as the board with the bad caps, so I can't just look at it to confirm for myself ).

Appreciate if anyone can let me know voltage for these 8 capacitors:

1000uF / 105°C x 1
1000uF / 105°C x 2
680uF / 105°C x 2
47uF / 105°C x 1
33uF / 105°C x 1
1uF / 105°C x 1

thanks!

[smason]

Re: Lg l204wt

From my notes on 2 of this model, I have replaced:
1uf @ 50v x1
47uf @ 50v x1
680uf @ 25v x2
1000uf @ 16v x2
1000uf @25 x1