Samsung plasma TV not working please help

[Hemant007]

Hi, greetings, I am looking for help, I got Samsung plasma TV ps43e450a1w,
From a friend it's not working, The issue is no display no sound, screen looks ok.

When I connect TV to power, I get the standby light, no clicking, no display, no sound.
I opened the back panel,
The green led on logic board flashes but it's not every second, its on 5sec, off 2sec,...
I disconnected Ysus board, but still no display no sound, no change to green light on logic board,
I disconnected Xsus board, but still no display no sound, no change to green light on logic board,

Visual observation- it looks all ok except on Ysus board one of the blue transistor is burnt (one near heat sink and big capacitor)
I am not sure if I need Ysus board replacement or any other fault.

I started checking some voltage.
On power board
PS ON 3.2 which reduces to 0 on switching On TV
A5V is 5.2

On sticker it suggests Va 58 and Vs 209,
As soon as I switch on TV,
Va reduces continuously from 208 to 10
Vs reduces continuously from 58 to 0

On Ysus board
As soon as I switch on TV
SVT VS reduces continuously from 208 to 10
SVT VE increases to 16 and then reduces to 10
STV YOUT remains 0

On Xsus board
As soon as I switch on TV
STV VS reduces continuously from 208 to 10
STV XOUT increases to 12 then reduces to 10


Please help how to find the fault and what do I need to replace?
Thank you

[tvtimmy]

Re: Samsung plasma TV not working please help

Take out the x main and check the igbt's and the driver ic marked in yellow.

[tvtimmy]

Re: Samsung plasma TV not working please help

Here is the repair kit.

[Hemant007]

Re: Samsung plasma TV not working please help

Please see attached photos of the boards.
Please advise which board seems to have fault?
Thank you

[Hemant007]

Re: Samsung plasma TV not working please help

From the above voltage Measurements, does power board seem ok?
Which board should I test more and how?
Please help, thank you.

[Hemant007]

Re: Samsung plasma TV not working please help

Looking for help, please advise

[dick_barton]

Re: Samsung plasma TV not working please help

Have a read through this thread especially post #5
https://www.badcaps.net/forum/showth...ps43e450a1w%2C

[Hemant007]

Re: Samsung plasma TV not working please help

Thank you, I checked the post, I am slightly unsure if it's power board problem, how should it differ with good psu?

On standby I get
A5V - 5.2,
PS ON 3.3


With Xsus and Ysus disconnected,
When I press power button on TV remote, I get
Vs -0
Va -0

Connected Xsus,
Vs - 208 drops to 10
Va - 58 drops to 0

Connected Ysus
Vs 208 drops to 10
Va 58 drops to 0

There is no sound no picture.
Ysus board has one blue transistor burnt, so I believe I need to replace Ysus board, but how do I check if there is another fault?
There is no sound even when I disconnect Ysus, what could be reason ?
Thank you.

[dick_barton]

Re: Samsung plasma TV not working please help

Post #5 on that thread tells you how to check the power supply. Some power supplies require a load ie bulbs for VS to come up.
If you have a burnt device on the Ysus board then that board probably needs to be replaced.
Show a pohoto of the board and a closer one of the burnt component.

[Hemant007]

Re: Samsung plasma TV not working please help

Please see attached photo of burnt component, a blue transistor / ps,
C5089 I think could not read properly so not 100% sure.

Also how do I test Y buffer board, I attach photo of pins on buffer board, none of these is labelled as ground to test short with other pins on buffer board.
Thank you

[dick_barton]

Re: Samsung plasma TV not working please help

If you look on youtube there are a few videos showing you how to test the buffer boards.
Here's one
https://www.youtube.com/watch?v=3Oq2MsU0XOQ

[Hemant007]

Re: Samsung plasma TV not working please help

Thank you, I did see the YouTube videos about testing buffer board, but am confused if I just select any pin on connector to Ysus board and check continuity to all the pins connecting to screen? Or do I need to select any specific pin on connector to Ysus ?
I attached photo of connector on buffer board showing pins, I was hoping one should say ground which I could select for testing, thank you

[dick_barton]

Re: Samsung plasma TV not working please help

This video should help you in how to find ground connection
The buffer boards need to be removed for testing but importantly note that the connectors to the flat cable connecting the buffer to the plasma screen need to be flipped upwards so that the flat cables can be removed carefully so not damage them or your set will be scrap.

Have a good look through Youtube where there is plenty to see before you remove the board if you feel uncomfortable doing so.

https://www.youtube.com/watch?v=V6hxf9sARMY&t=9s

[Hemant007]

Re: Samsung plasma TV not working please help

Thanks, I did watch that one also, he does not tell how he selected ground !
Is it OUTL labelled pin I should pick for testing ?

[dick_barton]

Re: Samsung plasma TV not working please help

Post a sharp picture of your ybuffer board so that the silk screen can be read.

[Hemant007]

Re: Samsung plasma TV not working please help

I replaced Ysus board which had C5089 burnt.
After replacing Ysus board, TV is working now :-) really appreciate all your help, thank you.

I was wondering if I can find replacement of C5089 so I can fix the old Ysus board ?
Thank you

[dick_barton]

Re: Samsung plasma TV not working please help

This looks like the repair kit for your Ysus board.
https://www.ebay.co.uk/itm/SAMSUNG-P...-/332414774095
Give them a ring and see if this includes C5089

[Hemant007]

Re: Samsung plasma TV not working please help

Thank you, that's good idea, will check with the seller.