[Tabloka]

The easiest way to check if the problem is the BV7 itself or the SAMSUNG panel is to connect a external monitor e.g. to the Display 2 port (HDMI 2). The manual says:

‘Another possibility for fault finding is to connect an external monitor to either the
HDMI 1 or HDMI 2 sockets. This will indicate whether the signal path is OK
through the DVE module (PCB05).’

If the screen then is okay you can search the fault in the panel.

[Tabloka]

jvezina wrote:

To find the exact capacitance of the cap, the only way would be to remove it on a working board, measure it, and put in back in place. Perhaps also there is a schematic of the T-CON board somewhere.

So it is! But the problem is that to remove a working t-con board from the BV is too time-consuming and I think that nobody “destroy” a good BV7-40 only to get the value of this tiny capacitor. If anybody owns a working t-con board for the BV7-40 MK6 and want to sell it … here is your buyer!

I tried all to get the schematic of the t-con board but without success. I wrote an email to SAMSUNG with the result that they said, ‘It’s a B&O and therefore we have no schematics or manuals for the panel or t-con or LED driver’.

The answer from B&O is, ‘We don’t give any documents to end customers and by the way it’s a SAMUNG device’.

It is really frustrating to deal with such arguments. Maybe some day WE – and of course the manufactures – realize that we have to get rid of the “throwaway society”.

[Tabloka]

Hello Dennis,

correct! No additional fault but I have no information about the faulty cap. When I see it correctely the cap works parallel with another cap against GND and is in line with a coil. So it is only a filter.

If you have the same problem with your MK6 unplug the LVDS cable and check if there is a short in the supply chain. If you find 0 ohms between the fuse and GND then it could be the same problem as mine.

Good luck.

[Tabloka]

jvezina wrote:

… Repairs at the component level on this board are difficult without a schematic …

… but it is not impossible. As I wrote in my last message, I found the bad cap and replaced it. And … THAT WAS THE FAILURE!!! The TV works very well again. Last night my wife and I tested the TV without any problems.

I found no sticker on the LCD panel but now it is possible to read all the information out of the service menues. The SAMSUNG LCD panel has the product no. LTA400HL11 and is the type LCD-40 HL-11. The t-con board has the SW version 20111013-011353 and the HW version 5130F52A.

If anybody can say what cap has to be the C10 please let me now.

[Tabloka]

Hier einmal ein kleiner Nachtrag:

Inzwischen bin ich dem Fehler auf der Spur. Nach Lösen des LVDS Kabels vom t-con board, stellte ich einen Kurzschluss auf dem t-con board am Eingang fest. Als Übeltäter war ein SMD Kondensator (C10) für den Kurzschluss verantwortlich. Nach Wechsel des Kondensators war der Kurzschluss weg und die Versorgungsspannung von 12V DC konnten am Eingang gemessen werden. Im t-con board war wieder Leben zu spüren.

Als Erfolg dieser ERSTEN Reparatur konnte ich die fehlenden Spannungen auf den anderen PCBs messen. Auch die 24V DC auf dem Power Supply sind nun da! Das Backlight ist auch wieder vorhanden.

Dies ist ein riesiger Schritt in die richtige Richtung. Nun das Bild wird noch nicht angezeigt. Vermutlich ist noch ein weiterer Fehler auf dem t-con board.

Ich packe mal ein Bild von meinem t-con board hier rein. Vielleicht hat ja nun einer von euch einen Tipp, wo es weiter gehen soll.

[Tabloka]

I dismanteled the LCD panel and could check the LED stribes. These are edge stribes with the number for L/H G1LE-400SMC-R6 and for R/H G1LE-400SMD-R6. Unfortunately they are NOT defect.

@jvezina: I couldn’t find any sticker. But I have to say that I didn’t remove the last layer. Nonetheless I could remove the two stribes.

[Tabloka]

Guy wrote:

Can you find a part number somewhere, search for another brand TV in which the panel is used and then find a YouTube video to explain dismantling the panel itself?

Does anybody know where to look for the part number in the Beovision 7-40 MK6?

[Tabloka]

Guy wrote:

EDIT: This video was also quite useful: https://www.youtube.com/watch?v=77tymvTJDxo

This video is quite interesting for my repair attemps. I have to look at the video a couple of times. Despite this is a B&O Beovision there is a SAMSUNG LCD panel inside. I don’t know which one but the video is great.

Thanks a lot. Michael

[Tabloka]

… Check the service manual for the Beovision 7-55 that has LEDs.

Hello Jean,
I don’t know where to get the Service Manual for the 7-55. In Beoworld.org there is only a user manual available. Any proposals?

Michael

[Tabloka]

jvezina wrote:

… But before, checking if the 24 volt supply to the inverter is present is the first step…

That is maybe a problem. Because the Mk6 has no CCFL but LEDs there is no inverter but a driver board. And I think when one or more LEDs are not working, the whole panel gets no power (24V) for safety reasons. I am not sure about that but I am quite sure.

As I wrote above: PCB03 P005 Pin2 should be 5V but is only 3V!

Regards Michael

[Tabloka]

Hi Jean,

my 7741 has also trouble with the backlight. Someday during televison the screen went black and never get back again. I sent the TV to my dealer for repairing but he couldn’t fix the problem. So I got the TV back unrepaired.

I read a lot of backlight problems and also watched a lot of youtubes about this topic. In your comment it sounds that you maybe fixed a problem with the backlight by yourself. Do you have any suggestions to dismantling/disassabling the TV in order to get to the LED stribes?

Meanwhile I checked most of the DC voltages of the PCBs compared to the service manual. So far I found only one DC voltage which should be 5V but it was only 3V (PCB03 P005 Pin2).

Thanks in advance Michael

[Tabloka]

Hat jemand für den oben genannten BeoVision 7-40 3D (Typ 7741) ein Service Manual? Kann auch in Englisch sein.

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