LG W2234S-BN Monitor Not Turning On: Power LED Off, Capacitor Voltages, PCB & Inverter Issues

Hello.
I have a beaten monitor, as in the subject. I looked through the forum and read all the topics devoted to similar symptoms, but I did not find a solution.
After connecting the power supply, nothing appears on the monitor, the "power" LED is off. I suspect that this is not the fault of the PCB with logic, because when connected to a computer, it is correctly detected (ie it correctly gives the available modes of operation, the resolution can be changed). You can not hear the inverter "cycling".

Obviously, I took the monitor off, and with the open instructions I took measurements as far as I could. Here is what I measured:
- capacitor voltages:
- C804: approx. 305-310V
- C806: 130V
- C805: approx. 3.3V
- C828: around 100V
- on C805 and C828, the meter indicates 30-37 V when measuring AC

- C817-819, C501, C528 and C815: around 18.5V
- C820, C822-824, C816: about 5V
- C807 (the one with IC802): 14.3 V

- On the logic connector (CN801) there is 5V on the power lines.

- on IC802:
1 (BNO): 3.55 volts
2 (COMP): 1.4 V
3 (LATCH): 6.25 volts
4 (CS): 0 V
(5 = GND)
6 (OUT): 0 volts
7 (Vcc): 14 V
8 (OVP): around 1.3 V

- on IC801 (is the photomultiplier called?):
- between 1 and 2: 1.1 V
- between 3 and 4: 1.4 V

- on IC803:
- AR: 2.5 V
- AC: 3.6 V
- mass-level anode at the logic connector (CN801)

- MOSFETs:
- D804: short 2 legs; the center is around 18 volts
- D805: as above, relative to the center approx. 5V
- U501: DG = DS = 18.4 V
- U502: DG ~ = DS ~ = 18 V (there is a difference of around 0.5V)

- On IC 501 I measured, following the procedures from the manual
- foot 9: 18.5V (Apparently, it should be 16V, but I do not know if this is not about the state turned on - how the power LED lights up.)
- foot 8: 0V (Also something supposedly should be - as above)

In addition, the tiles look fine, the capacitors are not bulged, you can not see any signs of burnout. Unfortunately, now I do not have the possibility to upload photos, but if someone suggests that they would be useful, I will get a camera

Thanks in advance for all the help.

IC801 - optocoupler
Initially, you can say that the power supply is functional.
You can take care of the TSUMU18ER board
See if there are 1.8V and 3.3V voltages

The fact that after connecting the monitor to the graphics card causes its 'detection' in your case means only communication with EEPROM from EDID

In this monitor

Quote:

W2234S-BN

procekTSUM18ER-LF
eprom 24?02
fleah 25lv010 / MX25L1005
invertor on: mp1008es / + field 9971gh 9575gh
power supply: 7n60 + ld7522p scaler

you have a flash problem with 90%
Below you have sucked in from a good one

WojtasJD wrote:

IC801 - optocoupler
Initially, you can say that the power supply is functional.
You can take care of the TSUMU18ER board
See if there are 1.8V and 3.3V voltages

The fact that after connecting the monitor to the graphic card causes its 'detection' in your case means only communication with EEPROM from EDID

Thanks for the information
I fumbled in googlu and I did not find the datasheet of this TSUMU18ER unfortunately. In the manual of the monitor, in turn, the logic circuit diagram is so vague that I do not know where these voltages should be
Any hint?

@lisek:
Thanks for the batch! Somehow it takes a lot, I understand that it's a question of how to make a dump (on the net I found reels much smaller - probably partial?)

So U103 is EDID flash, and U108 - flash main software?
It would rather fit me - because if I had to flash, then from what I see, U108 goes for SPI, and U103 after I2C (I think SPI will be easier to assemble).
(I ask you a lot of questions - excuse me, but I prefer to make sure than to do something stupid.) This is the last one: I can not put a load on this U108 without desoldering it from the PCB?

Added after 3 [minutes]:

And, still:
If it communicates with EDID and changes its resolution, does it mean that the processor (TSUMU18ER) is operational (still )?

There are not many LDO stabilizers, you can do it ...

WojtasJD wrote:

There are not many LDO stabilizers, you can do it ...

Aaa ... So that's how got a hint, thank you (and it's nice to know that there is such thing as an LDO stabilizer ...)

Thus, 3.3 V and 1.8 V are. So what's next?

@ Fox:
Is this a newer version with which there is no problem anymore?

@_Fox:
Something does not suit me - he has 512kB, while flash MX25L1005 has 128!

Since it is 1.8V and 3.3V, you can check the presence of quartz legs

Okay, I think it's time to admit what I've recently figured out. In short, I suspect that it's actually the fault of the batch - but the bone eeprom (MX25L1005) apparently damaged itself by stupid repair attempts.

But in turn: First of all, I could not stand it, and before WojtasJD suggested to investigate the quartz, I soldered SPI programmer after LPT (by Rayer) quickly. Being convinced that I will not be able to solder U108 anyway, I just soldered the cables on the board to it.
Of course, nothing could be read, so I began to combine with desoldering, but ineptly - using a braid. With these treatments it is possible that I flooded the system on one side. It was not until the next day that I realized that it was possible to desolder it with the help of a needle pressed gradually under my feet.
So I had a desoldered chip, and I was happy to see that Rayer's programmer can see him Joy did not last long, because after loading a new charge (from the base), when I read it several times, I received other discharges each time. In addition, the SPIPGM program detected the eeprom as a model with 64k instead of 128k.
So, apparently, the

Then Wojtas's post appeared and I made attempts to measure the quartz. However, I did not take an oscilloscope, because temporarily I have access to it (renovation). I tried the multimeter - and it's weird here, because it usually shows some nonsense, but sometimes with these measurements the power LED lights up in blue (!) And then it sometimes shows around the correct (?) 14 MHz. I also found in my "junk" some other, desoldered from somewhere quartz for this frequency - soldered in place of that and the same symptoms.

And what to think about it now?

PS I had such a doubt yet: in programmer according to Rayer I used around 160 instead of 150 R - could it have been something?

[EDIT]
Actually, the most important question now is whether you can replace the MX25L1005 with a different memory. I found 25LC1024 on tme, but she is on 20MHz - does that exclude her? Can it just run slower? (Would it mean a longer turn on the monitor or something else ...?)
[/ EDIT]

Weee!

Thanks all!
You said it well - fault on the side of the flash.
And I had a good feeling - you can successfully replace the MX25L1005 with a different bone with the right parameters. I managed to with something that costs something under PLN 3 instead of several dozen (like MX25 ...).

The monitor works and works well

Can not you write what you replaced right away ?!

Piter. wrote:

You could not write what you replaced right away ?!

And yes and not
Ie. calmly - I do not want to hide what the bone is, but just as I wrote it, I did not remember it, nor did I have the opportunity to check it out.
Now I saw: this flash is EN25F10 .

I bought several experimentally and I could not program for a long time - the problem was that the only simple programmer cooperating with this bone ( SPIFlash ) tried to run from emulation under the [/url] (wine), and it did not work - it started, the program did not see memory. Well, I did not have a computer with Windows and an LPT port.
In addition, this bone apparently can only be programmed once - so at least claims SPIFlash.

Moderated By Dzimi:

post has been corrected.