LG 42LC51-ZA (LP78A) - EAY34797001 Power Supply: Missing 3.4V, Backlight, No Picture

Question

Hello, I have traced the topics on the forum but I did not find hints, LG 42LC51-ZA (LP78A) is backlight and no picture, I found 3.4V voltage in the EAY34797001 power supply voltage before Q208 Q209 5V transistor. So I stabilized the stabilizer so that I get 3.4V and there is no sound image.
Does anyone have any idea or link to the power supply schematic?

piotrusek29 · Answer

Link to the scheme Added after 2 [minutes]:  If you can not download it, it is also here

mirex · Answer

You guarantee that there is a schematic of the power supply, should I then ask for a refund of 10 USD? Ehhh ... helpers.

piotrusek29 · Answer

I will not give a guarantee because I did not download

lisek · Answer

There is no scheme for this power supply PLHL-T604A (EAY34797001) from LG.
He is on a universal print (pcb EAX32268301 / 9) and depending on the level of completion in active and passive elements, and the needs for the output drive has different names. look
Link_popatrz on fot.2 / z_5_prawa page
or
Link_na Bottom foto.

In some versions plasm from LG to + 3.4V is not needed.
It was written in several forum posts.

p.s

https://www.elektroda.pl/rtvforum/topic2152741.html

No picture is ... not only the lack of these + 3.4V.

lamer. · Answer

Why paste this? And then there are claims to mocked advice. If the moderators dealt with such advice quickly enough, there would be no irony.

kasaki · Answer

The 3.4V voltage is applied to the LP78A / PP78A module EAX32572503 / (1) version of the software version 37LC41-ZA v: 3.09
Other voltages in the power supply are ok electrolytes changed from the description of the owner the image deteriorated gradually until it disappeared, after taking this nap. the effect is the same, is the motherboard dead?

lisek · Answer

Give me a break from Main.! Read (on the forum) and measure something on the T-Con 6870C-0119A for the LC420WX6-SLA1 matrix p.s yes, it probably is done + 3.4V per ssb - the transistor's battery is connected under the pin. 2 (on the left side (link) CN800 check where the transistor base is controlled and if there are sometimes breaks in the circuit, that it does not release this voltage

mirex · Answer

Why do you need these pictures for him? It has a module, in nature, before the eyes.

kasaki · Answer

Hello, I have not dealt with this problem for a long time but I am coming back and I want to finish the case.
Colleague Lisek was right! The CTRL T-Con LC420WX6-SLA1 6870C-0119A logic is damaged. Specifically, the fuse F1 flared and the chip TPS65161 SMD on L1 is 3.3V, while the L2 12V should probably be around 18V.
If someone has already exchanged this chip TPS65161, please let me know if it moved after the exchange

mirex · Answer

I did not move. There was something else. But my friend succeeded. He went from the kick.

kasaki · Answer

Layout TPS65161 replaced TV LG 42LC51-ZA Works! Ps. I think that this forum goes to the dogs many servicemen do not write anything outright misleads for fear of losing money.

LG 42LC51-ZA (LP78A) - EAY34797001 Power Supply: Missing 3.4V, Backlight, No Picture

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