Samsung QE50Q50TAU No display &sometimes restarts

[burbutsalos]

Hello, I have been trying to see what the problem is with this TV.
After doing some tests i found out that the must be some kind of short on the panel.
The problem is on the main side of it . By testing in didode mode i find a pair of capacitors on each cof short. The panel has 7 cofs so i can see 7 pairs of capacitors with problem.
This only happens when the tv is on and the cables to the panel connected. You can hear sound but ths screen is kind of ...dark blue.
Changing the channels turns the screen black momentarily and then the screen changes to dark blue again.
Any ideas what to do? Could it be a Tcon(mainboard) fault ? I tried testing the capacitors there but no short found.

[angelos]

Re: Samsung QE50Q50TAU No display &sometimes restarts

Hello, I have been trying to see what the problem is with this TV.
After doing some tests i found out that the must be some kind of short on the panel.
The problem is on the main side of it . By testing in didode mode i find a pair of capacitors on each cof short. The panel has 7 cofs so i can see 7 pairs of capacitors with problem.
This only happens when the tv is on and the cables to the panel connected. You can hear sound but ths screen is kind of ...dark blue.
Changing the channels turns the screen black momentarily and then the screen changes to dark blue again.
Any ideas what to do? Could it be a Tcon(mainboard) fault ? I tried testing the capacitors there but no short found.

Mr Burbutsale Kalimera sou,
On most Samsung's i have encountered panel problems. Sometimes we can work around the issue but other times it is a no fix.
First of all you need to take proper photo's of the TCON and scalar boards.
We need to determine if you are getting any voltages on the tcon feeding the panel.
These are VGH, VGL, AVDD and HAVDD. On Samsungs they might have different names.
So first thing, a closeup of the TCON. If the TV does not have a TCON because it is built into the main board then you need to take a closeup of the area where the LVDS ribbon plugs in.

[nomoresonys]

Re: Samsung QE50Q50TAU No display &sometimes restarts

It probably just sounds odd the way you worded it but just to be clear, diode testing is done with tv unplugged from power. To be sure those caps are shorted you want to isolate them by unplugging the cable/s from tcon to driver boards on tcon side, this will insure that the short isn't jumping from mainboard or tcon to driver boards.

[burbutsalos]

Re: Samsung QE50Q50TAU No display &sometimes restarts

Thank you both for your answers Mr Angelos (patridaaa) and Mr. Nomoresonys.I did the tests with the power disconnected and i had the short. Unforunatelly and maybe because i am a complete newbie to this i decided to try removing one cap at a time test it and see if the short went off and then put it back on if not. I Started with the ones that showed less resistance.What happened was that after the removal of the 4th or 5th cap (..a few hours later ) , i plugged the tv on and heard i hissing sound and i burning smell... !!! Yes one of the cofs made wonderfull liitle sparks!!! So that was the end of the tv.. Went to recycling !!!