samsung Ps43d450a2w power board failure

[xmandarkx]

hi, i have a samsung Ps43d450a2w plasma tv and during recent power cuts it has stopped working. i did some research and have tried unplugging x and y boards but nothing works.
i get the green flashing light but my vs and va voltages are 0.
the relay only clicks when i plug in and unplug the power cable.

any help pointing in the right direction would be most appreciated
cheers.

[tom66]

Re: samsung Ps43d450a2w power board failure

Do you briefly get Vs and Va from power board with X- and Y-main unplugged?

Any power light on TV?

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

no, no voltage at all with or without x and y attached.

the red light comes on on the front when you press the button but nothing happens.

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

i do get 15v on one of the pins just not va or vs.

[tom66]

Re: samsung Ps43d450a2w power board failure

OK, can you post a picture of the power supply board, clear and in focus?

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

picture of power board

[tom66]

Re: samsung Ps43d450a2w power board failure

So, to confirm, you get 0V on the Vs point, bottom left of that photo? Does this change at all as the TV attempts to power on? Red probe on Vs point, black probe on chassis, highest DC range on meter (e.g. 600V or 1000V.)

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

where is the best place to earth the probe to? i will check now.

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

put probe on vs and plugged the power cable in and got 206v dropping to 10v and pressing the power button on the front makes no difference.

[tom66]

Re: samsung Ps43d450a2w power board failure

OK, PSU looks to be working. Now, check indicator light on control board, just below power board. The light should flash, either once a second approximately or once every 5~7 seconds. What does it do?

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

it stays on for about 7 seconds then off for a couple then on for 7 etc.

[tom66]

Re: samsung Ps43d450a2w power board failure

OK, you have an X- or Y-main fault. The X-main is the most common fault, but both boards should be replaced at the same time, as the failure of one can damage the other. You don't need to replace the buffer board.

After replacing the boards, remember to update the TV's firmware.

See here:

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

so to confirm, power board is ok, replace x and y boards then update firmware and its good to go?

thanks very much for your help.

[tom66]

Re: samsung Ps43d450a2w power board failure

Yes.

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

i have replaced x and y boards and nothing has happened, its exactly the same

[tom66]

Re: samsung Ps43d450a2w power board failure

Is the control board indicator light doing the same?
Check the panel for slight cracks around the edge.

[tw2005]

Re: samsung Ps43d450a2w power board failure

Just a thought,

It might be worth trying the built-in test patterns on the logic ctrl board and bypassing the mainboard..

Have the Tv powered off, then remove the power cable from the mainboard .

There should be Jumper pins 2-4 on the logic board,

with the power lead for the main, jumper pin 1 (PS on) to GND (pin 5). should be able to do it at the connector end with some wire or maybe a paper clip

plug Tv in and apply power and see if you have the same issue or if the panel comes on and test patterns.

You can get faulty boards supplied, they're not always tested out of broken Tvs.

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

hi yes the light is doing exactly the same, i cant see any cracks in the panel.
i did what tw2005 suggested and still no difference. i did briefly get a white flash on the corner of the display once.

[tom66]

Re: samsung Ps43d450a2w power board failure

Could have got a bad board... check any transistors on them. Post a picture of the underside if you need help locating the transistors to test.

I got a bad board for this model, X-main. I think about 10 to 20% of boards are bad because people smash their telly when it stops working and put it out on the curb. eBay sellers don't test their boards.

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

it said it was from a working set with damaged screen and fully tested and working board, which board do you want the pic of?