SAMSUNG PLASMA 50INCH PS50Q7HD With No Picture But Has Sound


	FORUM HOME	SEARCH POSTS	WHO'S ONLINE	LOG IN	RULES F.A.Q.

TV Forums: TV Equipment: Plasma TV Forum:
SAMSUNG PLASMA 50INCH PS50Q7HD With No Picture But Has Sound - Replacement Parts Fitted?!

Print Thread

FabWebHost
New User

Mar 24, 2015, 7:30 PM

Post #1 of 2 (2808 views)
Shortcut

SAMSUNG PLASMA 50INCH PS50Q7HD With No Picture But Has Sound - Replacement Parts Fitted?!	Can't Post

I bought a SAMSUNG PLASMA 50INCH PS50Q7HD secondhand 4-5 weeks ago. The t.v was spares & repairs (Ł40) and I understood at the time it had no picture... But it had sound!

I done a bit of research before buying it and read on the net it was probably the Ymain & buffer boards faulty and a quick look on ebay prompted me into getting the tv as spare were available. On getting the tv home (after buying it) I decided to switch tv on and within minutes there was a small pop and a little smoke came from the top right of the set.

After letting the tv power down for an hour I decided to take the back cover off and have a look...I quickly discovered that the Ymain board had a few blown diodes, which indicated a problem!

I also read that, as a certain section of the Ymain diodes had blown, it was likely my bottom buffer caused the ymain to go................ It seemed an easy fix!!!!

Anyway..... I ordered a new Ymain board and a pair of buffers from Cradeal.co.uk which arrived today! I have now fitted them to TV. Unfortunately I still have no picture just sound, which was the original problem!

The TV cost me Ł100+ and the moment :(Any advice would really be appreciated, as this is the second package from cradeal after they sent the wrong parts last time??!!

Please understand im a fixer, not a thrower :)

(This post was edited by FabWebHost on Mar 24, 2015, 8:49 PM)

omendata
New User

Jul 26, 2015, 7:30 PM

Post #2 of 2 (2361 views)
Shortcut

Re: [FabWebHost] SAMSUNG PLASMA 50INCH PS50Q7HD With No Picture But Has Sound - Replacement Parts Fitted?! [In reply to]	Can't Post

This is a nightmare common fault with plasmas and difficult to pin down.
I am dealing with the same issue on my 50LGPK590 myself.

I have repaired the psu which i thought was the issue - common problem with the two 22ohm 5 watt resistors and sometimes a diode and smps transistor but the tv powers up now.

Just very depressing that i also have no picture but have sound.

I have tested the y-buffers today and they are fine - i bought a y sustain board off ebay and it didnt fix the issue.

Someone has said that if you pull the connection from the z-sus to the psu and you still have sound then its the z-sus board that has the fault but i dont agree with this - perhaps someone on here can confirm this as i pulled the z-sus and there is still sound indicating that z-sus board is faulty.

Having researched for two days it seems the problem may be with the actual t-con board itself.

If you have tested the psu vs , va and standby voltages when powered on from the y-sus and z-sus sides and the voltage is steady then its not your power supply.

Also you have to be careful withe the y-sus - if you plug a replcament board it into faulty y-buffers you can blow the board.

If your tv made a popping noise you can be sure its one of the y-buffer chips thats blown - you can usually tell by checking the top of the chips it will have a hole in it or scorching round any heatsink that might be on it - the crap tv's are the ones that dont have heatsinks on the y-biffer chips!

I think i will bite the bullet and buy a t-con board tonight and see what happens as I am sure its not the z-sus even though the advice is that it is if you still get sound when its disconnected.

Maybe someone more knowledgeable than i on here can give us some sort of clue.

I really need to get an oscilloscope to fix these things properly.
I have always got on fine with my fluke meter but for more in depth stuff like this you need and oscilloscope especially for testing the y-sus outputs.

Print Thread

Search for (options)

- Page loaded in: 0.17 s on (CGI/1.1)