Samsung 50" TV PS-50Q97HD wont turn on

[YeOldeGinge]

Hi, People

I have a Samsung 50" Plasma TV which will not power when I plug it in it makes a few clicking noises and the power light appears then when I click the power button it begins to flash 5 times then the light goes out as shown in the video.

I have visually checked all the caps by eye and none look blown.

If anyone could tell me what the problem and maybe how to fix it it would me much appreciated.

I have a good general knowledge when it comes to electrical devices and have fixed TVs before but this TV has baffled me.

TV's Details
Make: Samsung
Model: PS-50Q97HD
Model Code: PS-50Q97HDX/XEU
https://www.youtube.com/watch?v=Zf2dDgHRnLg

[sordids999]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Check to see if you have Vs + Va voltages on the power supply and also check for cold solder joints had a similar problem today

[YeOldeGinge]

Re: Samsung 50" TV PS-50Q97HD wont turn on

OK, would i have the TV plugged in while checking them and what setting on the multimeter should I use?

[sordids999]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Yes but be careful what your touching !
on the panel should be a sticker giving you what the voltage readings Vs Va should be use the test points on the power supply marked up Vs Va set your meter to DC 600 volts use black lead on panel chassis then red lead to test

[YeOldeGinge]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Ok ther is VA-TP and VS-TP are they the ones I should test

[sordids999]

Re: Samsung 50" TV PS-50Q97HD wont turn on

yes

[YeOldeGinge]

Re: Samsung 50" TV PS-50Q97HD wont turn on

OK thanks i will get back to you in a second

[YeOldeGinge]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Right for VS it was between 200V to 215V and I measured 206V and for VA it was between 60V to 66V and I measured 63V.

what does that tell you ?

[sordids999]

Re: Samsung 50" TV PS-50Q97HD wont turn on

While your testing voltages you could also test Vsc and Ve but i would also check the under side of the power supply also for any damage etc but leave the tv powered off for at least 15 mins before handling the power supply

[YeOldeGinge]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Right I have just measured VE at 94V and i have not been able to fine VSC are you able to send a more detailed picture? if not its fine a description will be as good

[sordids999]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Picture uploaded but i would also check for Q801 & Q802 on the underside of the power supply which if i remember its a common fault on these models

[sordids999]

Re: Samsung 50" TV PS-50Q97HD wont turn on

https://www.badcaps.net/forum/showthread.php?t=39514 see here also

[YeOldeGinge]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Right I have just measured the VSC and it starts at 170+V and slowly decreases voltage i am just waiting for the bored to discharge so that i can check the q801 and q802

[YeOldeGinge]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Anyone have any idea what could be wrong with my TV? could really do with some help! :P

[Alastair E]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Is there a tiny green LED lit on the Y-SUS board, (in bottom right hand part) when the set is turned on....?

[YeOldeGinge]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Is this the light you are talking about?

[YeOldeGinge]

Re: Samsung 50" TV PS-50Q97HD wont turn on

Help me!

[tom66]

Re: Samsung 50" TV PS-50Q97HD wont turn on

LED lit = fault on Y-main

[YeOldeGinge]

Re: Samsung 50" TV PS-50Q97HD wont turn on

What do you think the problem might be?

[Alastair E]

Re: Samsung 50" TV PS-50Q97HD wont turn on

The Y-SUS is in 'Protection-Mode' hence that LED.

The protection circuit monitors three things. The ERC circuit, the VSCC and summit else that I cant recall...

I have one exactly the same--and same fault. Spent probably 50 or 60 hours on it, and no progress. Many parts replaced, no obvious faults. I'm suspecting one of the ERC or other MOSFETS/IGBT's is O/C....

This fault (If the same fault as mine--and Ive seen two Y-SUS with this fault)--Unless you stumble on it is NO quickie.

Replacement Y-SUS (05120A) are expensive and in short supply.

First off for yours--Check for shorts on all the silicon power-devices of the Y-SUS, also check the small fuses on the supplies to the DC/DC converter stage--Thats the part the protection circuit shuts down via a quad-comparator....