Samsung Plasma 50 inch picture problem

[pval3233]

SAMSUNG 50 INCH PLASMA PS50Q97HD
Before I ditch my TV which has Sound with no Picture problem I thought I would put a post out and see if there is any rescuing it. I have tried all the tests on the forum and also followed every link through to the help videos and still no joy
I had 4 capacitors on the PSU bulged so I replaced all 4 with higher voltage caps
Green light on Y sus board so ordered and swapped this, Buffer board top IC blown so swapped both Y buffer boards
I have tested every possible voltage and everything is testing as it should, i cannot find any cracks on the screen with the lights off using a torch and there is no flashes when first switched on it just does nothing except crystal clear sound. The only thing i can see but don't know if this is a problem is the LED on the logic board flashes a little more than once per second maybe around 30 flashes in 25 seconds
Any ideas before i through away would be appreciated

[tom66]

Re: Samsung Plasma 50 inch picture problem

Look carefully at the Y-main board. Down by the connector which hooks onto the logic board there should be a little LED light. Does this glow?

Also, look in a dark room. Can you see any screen glow?

[pval3233]

Re: Samsung Plasma 50 inch picture problem

Hi Tom

No LED lights on Y main board and no glow from the screen

Put all lights out and watched with TV turned on and no glow at all

[tom66]

Re: Samsung Plasma 50 inch picture problem

OK, have you checked your have good Vs going to Y-main board?

[pval3233]

Re: Samsung Plasma 50 inch picture problem

Yes tested Vs and all correct

[pval3233]

Re: Samsung Plasma 50 inch picture problem

Does this mean my Y-main board is ok?

[tom66]

Re: Samsung Plasma 50 inch picture problem

Can you see places to test the Vsc and Vset voltages on the Y-main board?

[pval3233]

Re: Samsung Plasma 50 inch picture problem

I can only see Vs and Va test points on the power board!!

[tom66]

Re: Samsung Plasma 50 inch picture problem

Sorry, my error. I meant Y-main, post edited.

[pval3233]

Re: Samsung Plasma 50 inch picture problem

Sorry Tom, can see a test point for Ysc near bottom left hand corner of Y main which is testing as it should

On Y main top right (at power board connection) I have Vs and Vcc which are all testing as they should also

[tom66]

Re: Samsung Plasma 50 inch picture problem

Any sign of Vscan?

[pval3233]

Re: Samsung Plasma 50 inch picture problem

No I don't see any Vscan test point on Y main

there is a box in the middle of the Y board which says UP with Vscan written below it and an arrow pointing down to the left but don't see a test point

The only other test points are Vs and Ve on the X main

[tom66]

Re: Samsung Plasma 50 inch picture problem

Can you post a clear photo of the Y-main board. I could swear there are test points on it, but now I'm not certain.

[pval3233]

Re: Samsung Plasma 50 inch picture problem

will do Tom, will need to be tomorrow

[pval3233]

Re: Samsung Plasma 50 inch picture problem

Found Vscan test point Tom whilst taking pictures, it is testing -194

If Vsc is the same thing then panel on back of TV says it should be -195

[pval3233]

Re: Samsung Plasma 50 inch picture problem

Hi Tom Vscan testing at -194 on Y main board