Samsung Lcd Tv Black Screen

[Bazzamer]

 
Hi All, From all of what i have read so far this is a wonderful site hope someone can please help.
I have a Samsung LE46C530F1WXXU which like many others has a problem, it will power on get the chime a flash of the screen then it sits black and can not see anything, then 15mins later it goes into standby.
After seeing many others on the net with problems, i changed the caps and went up to 25volts even though they looked ok. I contacted Samsung and they advised was a power supply problem but the capacitors are not affected on this model, i do not have a service manual to work from so its difficult to check voltages. The power supply board is BN44-00341B was only made in 10-3-11. One thing i did try was to disconnect the T-CON ribbon cable and power up, it made no difference which led me to believe it could be faulty, i seem to be going round in circles, and possibly missing something simple, have even looked at replacing all the boards for £59 but none in stock. That is the easy way out and world just love to find the answer and fix it.
Any help would be really appreciated.
Many Thanks
Bazzamer   

[t1412]

hi when you get these problems with samsung no picture fault usually down to buffer boards and y sus board, these are located on the left hand side of the tv, check the main fuse on the y sus also the soldered fuses and, it would be best to check the fuses on the z board this board is on the right hand side good luck.

regards
shaun     

[dynomo]

One of those PSU's on Ebay £38  


http://www.ebay.co.uk/itm/Samsung-LE46C530F1W-Main-PSU-BN44-00341B-Working-Part-/170915046038?pt=UK_Sound_Vision_Other&hash=item27cb54a296

 

[sparky]

hi
your tv lcd forget y and z panels not fitted
is there a separate inverter board if so check the
fuses

[sparky]

hi
the psu have the inverter built in fit another power panel

[Bazzamer]

Hi Sparky,
Many thanks for the reply, unfortunately i just stripped it down looking for x and y but not in this model. The inverter board is on the right (looking from rear) has 14 mini transformers and all check out ok
The main power supply maybe the prob but most seems to check out ok, apart from a big diode that reads both ways, do you happen to have a service manual as if poss would like to find the problem, am a retired sparks and was given tv so plenty of time.
If i fitted a new board as a last resort would it be a case of fitting and then be up and running or would i have to do more, sorry if i am putting you on the spot. Am no electronics expert just know a little yes i know thats the worst kind do more damage than good, but thats how we all learn.
Many thanks for the help its really appreciated.
Barry

[watteau]

Hi,
Have you tried using a Scart lead from the Samsung to another set, to see if there is
any picture and sound coming out when the set is on?
If so, it's probably an inverter fault, especially if the screen
lights up momentarily at switch on.
Regards,
John.

[Bazzamer]

Hi John, many thanks for the reply, maybe a bit difficult to get 2 TVs close enough to do that maybe have a go later. I did try connecting my laptop to it via VGA, but could not get anything then I was playing with remote when laptop was disconnected and I got white noise from tv speakers, but I can't get it back again. Maybe I just got the remote on a correct setting, as I tried my iPod as well but still can't get anything.
It seems like one problem Leeds you one way then it get confusing as something else Leeds you in the opposite direction, it's doing my head in. Did check all tranies out all seem ok, but could be some other fault.
Thanks for your time.
Barry

[thoma]

Hello!
The servicemanual can be downloaded by http://elektrotanya.com/samsung_bn44-00341b.pdf/download.html
thoma

[Bartimeus]

Hi All

The fault you describe is common and can occur with almost any LCD TV.

If you are getting an image flash up when the TV is powered on and it then disappears to black 99 times out of a 100 it is an inverter fault. Inverters commonly fail due to heat build up damaging insulation in the coils on the inverter board which causes a short circuit shutting down the backlight.

The common way to confirm the fault for non techies is to shine a torch into the screen , you should be able to see that the image is still there as normal , you just can't see it because the backlight has shut down.

As previously mentioned you can also connect the AV1/AV2 scart sockets to another TV , if you get an image from the faulty TV on the second TV you can be sure that most other functions are OK . Connecting a laptop won't help you, you want the output from the failed TV to display on another TV.

In addition be , careful when purchasing spares from Ebay , quite a lot of spare inverters there are faulty , go with one of the larger recyclers with a good feedback history. they are more reliable.

[Bazzamer]

Hi Bartimeus, many thanks for the help. I am a little confused at the mo, on the power board are 2 large inverter trannies which feed and inverter board (high voltage) down the right hand side, are you talking about the small trannies which there are 14 of or the ones on the main power board ?.
I don't know how I got a sort of white noise from the speakers and I can't replicate it again, I do get the jingle of sound at startup but after being on for 15 mins it goes into standby mode, so maybe I have a couple of faults.
The main power board is BN44-00341B and the inverter board is Darfon model V235-10J.
Really do appreciate all this help, always wanted to do electronics but never had the time, now I have retired its very difficult as I have not got the room, at my age things tend to go in and out of the brain a bit quick ha ha.
Thank you all
Barry

[watteau]

Hi,
It's probably switching off after 15mins. because there's no signal.
If the set was tuned to your local transmitter, put into DTV mode, and try to get a station.
The Inverter PCB is I think, is on the right, it has a long (black) plastic cover over the PCB.
You can go through and compare the transformer readings for interest, but if you find one
that off, it's a good chance you won't be able to find a replacement.
Probably the best bet is to replace the complete Inverter PCB.
Regards,
John.

[Bazzamer]

Hi John, I connected a scart from my tv, with no aerial to the sammy, I get sound from sammy, if I remove aerial lead from my tv and put into sammy, I get nothing, and can't see any image with torch, I guess sammy is just acting as a extension speaker. The tv did stay on so it must be getting a signal of some sort as it never went into standby after 15mins. I did some tests on the small inverter trannies, ht side came out between 218 and 230 ohms on them all, other windings were different, some around 9 ohms up to 44 so seem ok but like you said could break down when in operation.
The set was possibly tuned into cable virginmedia and that's what I am on so should be no different, I don't know what is DTV mode and would know if it was in it as cant see a picture at all. Sorry John if I am being a pain, have you anymore ideas.
Many thanks
Barry

[sparky]

hi
best thing find local tv engineer

[bilsat]

I had a similar fault on my LCD TV, resoldered every inverter transformer connections, this cured it!