• Tv Scott tvx 150 biały ekran

Forum rules:Click here to view the forum rules

  1. Topic title should contain: the device's manufacturer, full model and the brief description of problem.
  2. Topic message should contain: the PCB marking code (required in case of hardware repairs), an extended description of problem, things you have checked/replaced/measured, your conclusions and the question. If you are not able to find the PCB marking code, please read THIS TOPIC. If you still cannot locate the PCB markings, please upload a clean, both-side photos of the mainboard - it is required to remove any films, modules or brackets possibly covering these markings.
  3. Before posting a new topic please read all topics in TRAININGS subforum and make a preliminary diagnostic based on the content of those trainings.
  4. Uploading of any complete schematics, BIOS / firmware files or any other kind of documentation, or linking to 3rd party websites with such files, is STRICTLY PROHIBITED. You can only upload the small portion of documentation or, link to BIOS file on UNVERIFIED BIOS FILES subforum, which simplifies the diagnostics/repair. You are not allowed to upload more then one complete page of instruction/schematic per single topic. The file you upload must not contain any watermarks, "confidential" markings, links or email addresses and cannot be password-protected.
  5. It is only permitted to describe one faulty device per single topic - you should always open a new topic for each subsequent device.
  6. Requesting of the full schematics, BoardView files, BIOS files or any other kind of documentation is NOT ALLOWED in this subforum. If you need to ask for any of these, you should open a new topic in DOCUMENTATION/BIOS REQUEST subforum.

#1 Tv Scott tvx 150 biały ekran


by Tomasz1979 5 June 2018, 14:06
Witam serdecznie elektromaniakow trafił do mnie ów tv, włącza się normalnie dioda z czerwonej na zieloną po czym biały kolor LCD,po ok. 5min wyłącza się.
Sprawdziłem bezpiecznik na logice matrycy - sprawny, ma przejście napięcie na nim 0,47V. Na inwerterze napięcia vcc 11,98V, ON 2,55V, VB 0,44V inwerter pracuje na scalaku TL494C
Gdzie muszę jeszcze pomierzyć? Dodaję fotki
Załączniki:
Image

podaję nazwę Main THTFTV1595 V1. 0
Zasilacz zintegrowany z płytą główną napięcie dedykowane 12V

Re: Tv Scott tvx 150 biały ekran


by Google Adsense [BOT] 5 June 2018, 14:06

#2 Re: Tv Scott tvx 150 biały ekran


by matic 5 June 2018, 19:25
Tomasz1979 wrote:Sprawdziłem bezpiecznik na logice matrycy - sprawny, ma przejście napięcie na nim 0,47V.
Hello!
It is missing LCD matrix power supply voltage.

Please post a clear photos of both sides of the main board in the matrix connector area.

#3 Re: Tv Scott tvx 150 biały ekran


by Tomasz1979 5 June 2018, 20:36
Image
Image

#4 Re: Tv Scott tvx 150 biały ekran


by matic 6 June 2018, 07:53
Please, post better pictures with visible marking on both chips in SO-8 package near the matrix connector.

#5 Re: Tv Scott tvx 150 biały ekran


by Tomasz1979 6 June 2018, 15:39
N28 and N11 in the board P-channel Mosfet APM9435.
N12 PWM Control AP1534
Image

#6 Re: Tv Scott tvx 150 biały ekran


by Tomasz1979 9 June 2018, 10:39
Hi, if you are more or less able to guide me, what should I measure? I noticed that the 15 ohm resistor R385 gets very hot, then the tv switches off. I will take a picture of this element and with it neighboring
Image

#7 Re: Tv Scott tvx 150 biały ekran


by Tomasz1979 11 June 2018, 08:25
Witam,co mam pomierzyć,czy ktoś spotkał się już z takim przypadkiem?

#8 Re: Tv Scott tvx 150 biały ekran


by matic 11 June 2018, 12:55
Check on which component the highlighted pins are connected.
It is probably connected to the transistor Q39 or N28.

Image

#9 Re: Tv Scott tvx 150 biały ekran


by Tomasz1979 11 June 2018, 19:17
Napięcia zmierzone na N28 i Q39
Image
Image

#10 Re: Tv Scott tvx 150 biały ekran


by matic 11 June 2018, 19:24
Actually, you didn't answer to my question.
matic wrote:Check on which component the highlighted pins are connected.

First use the continuity tester and check to which component the highlighted pins are connected.

#11 Re: Tv Scott tvx 150 biały ekran


by Tomasz1979 11 June 2018, 19:41
matic wrote:Actually, you didn't answer to my question.
matic wrote:Check on which component the highlighted pins are connected.

First use the continuity tester and check to which component the highlighted pins are connected.

I checked with the continuity tester, it only conducts N28. I marked it all in yellow
Image

#12 Re: Tv Scott tvx 150 biały ekran  [SOLVED]


by matic 11 June 2018, 20:13
If the voltages on the picture above were measured, when the TV was turned on, the "enable" signal on pin 4 of transistor N28 is missing.
This signal comes from the main micro controller chip, which is located under the metal shield.

The cause of the lack of this signal is probably corrupted firmware in FLASH chip (it is located under the metal shield as well) or bad main micro controller chip. I think it is more likely corrupted firmware.

The content of FLASH chip is probably unavailable, so I think the best solution is to replace the entire board with a new one.

#13 Re: Tv Scott tvx 150 biały ekran


by Tomasz1979 11 June 2018, 20:24
I've been looking for a new or used motherboard, but I can not find it anyway. I think so that the motherboard will be a part-donor. Wonderful for your interest in helping

Re: Tv Scott tvx 150 biały ekran


by Google Adsense [BOT] 11 June 2018, 20:24

Who is online

Users browsing this forum: No registered users and 0 guests

_______________________________
All rights reserved. Unauthorised copying of this website's content or any of its part is strictly forbidden.
Any trademarks, brand names, products or services published on this website belong to their legal owners, are copyrighted and used for information purposes only.