samsung Ps43d450a2w power board failure

[tom66]

Re: samsung Ps43d450a2w power board failure

Everyone says that!! Nearly no one tests them!

Y-main and X-main

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

pics of x and y

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

ps-on is 0.15v is that right?

[tom66]

Re: samsung Ps43d450a2w power board failure

PS ON is active low, that's fine.

Test each highlighted. Use diode range on DMM.

2 pin devices (diodes): test both ways, diode test. Reading of <100 = bad. Reading both ways = bad. Hold reading for 5 seconds before reading off.

3 pin devices (FETs, IGBTs = transistors): test all pins, NO READING (i.e. "1") for all pins EXCEPT a diode reading (200~800) between two pins (drain/source) on certain devices. Reading of <100 = bad. Reading both ways = bad. Hold reading for 5 seconds before reading off.

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

on x board i have 2 transistors that read the same on both legs and have continuity between them and the rest give a reading of 1 and 445 or 550

y board is the same, 2 have same reading with continuity and rest 1 and 445 or 550.

oddly the replacement board is exactly the same, so i guess both faulty then?

[tom66]

Re: samsung Ps43d450a2w power board failure

Yeah, I suspect so.

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

is it worth replacing the transistors or will i likely run into further problems?

[tom66]

Re: samsung Ps43d450a2w power board failure

not really worth it at the moment, boards are cheap enough -- return the board for a refund...

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

ok ill do that, where do you get your boards from? theres a lot on ebay that say tested but i cant trust that now

[tom66]

Re: samsung Ps43d450a2w power board failure

I got mine from parts4u.me.uk. The parts aren't tested but he sends out new boards free of charge if any are faulty. And very reasonable prices.

[xmandarkx]

Re: samsung Ps43d450a2w power board failure

cheers, i will check it out. thanks for your help.

[keithf2]

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.

tw2005, should the jumper be between 2 and 4 or 3 and 4 on the logic board

[stejones]

Re: samsung Ps43d450a2w power board failure

Hi just got one of these tvs and for some reason the picture as red and yellow in the screen can anyone help could this be a logic fault