Samsung PN50A530S2F Plasma Clicking Transformer BS

[Kridian]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

The whole point of the "panel" test is that you should get a very simple picture generated by the tcon with no input from the main board, that's why the mainboard needs to be disconnected (both power and the lvds cable).

Hmmm, the instructions on the test panel page didn't say to unplug the Main Board power connector. Just the LVDS. (?)

Because power is disconnected to the main board there is no way to turn the set on, that's why you put a resistor on the power supply connector that used to go to the mainboard before you disconnected it. This forces the power supply to start / and it should stay on.

I was instructed to put the resistors on the power connector leading to the Control (Logic) Board. (?)

Now the part I don't understand, because tom hasn't said it yet, is are you expecting the panel test to display a test pattern forever till you unplug set? or is it supposed to just be for a few seconds then turn off. Also is the test pattern the solid green screen that he got?

I didn't know exactly where all the testing was going. I guess seeing if the new Main Board was still the culprit.

Anyhoot, the new Main Board is back on there so I'm ready to go forward with more testing/ideas.

[tom66]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

Always order by PBA number, not PCB number. PBA are BN91, BN96 etc. PCB numbers are BN41, BN44 etc. PCB numbers code for the blank board which can be loaded in any number of configurations -- in your case with an extra (Reset?) button and a USB port, but perhaps many other possible differences making it incompatible.

The test pattern should display indefinitely if the main board keeps the power on. However just a few frames verifies the control board, sustain boards and panel are good.

The reason you put the resistors on the control board is because we suspect the main board is faulty and that it is causing the power to cycle. So the main board should be eliminated completely. In some tests where the TV turns on, panel lights up but there's no image we need to leave the main board connected.

The fault with these main boards is mostly firmware, sometimes EEPROM. The board will power on, decompress its firmware into RAM, and usually crash if there is some corruption to that firmware. This causes it to click on on, then click off. (These TVs run a very stripped down Linux kernel, I think. The B series definitely does, as it has open source credits.)

So, with the NEW part installed, and everything plugged in, you get rapid clicking only?

[Kridian]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

So, with the NEW part installed, and everything plugged in, you get rapid clicking only?

Correct, and no lighting on the panel at all. I made a video of it for what it's worth.

The fault with these main boards is mostly firmware, sometimes EEPROM. The board will power on, decompress its firmware into RAM, and usually crash if there is some corruption to that firmware. This causes it to click on on, then click off. (These TVs run a very stripped down Linux kernel, I think. The B series definitely does, as it has open source credits.)

Oh wow. That would be the death knell for this thing.

For the record, according to its little sticker, the new Main Board# is BN97-01985R. The original one is BN97-02185A.

[tom66]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

Yeah, you really need to match the BN97 number...

[Kridian]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

These two stickers were attached to the original Main Board. When doing a search with the bottom number (BN97-02185A), it only directed me to boards with the top number (BN94-01797B). I guess this is what I should be buying yes?


Here's a site that has one but no picture to confirm it. Wonderful. Would you pull the trigger and purchase it? Says it's brand new.

[tom66]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

BN94 numbers are preferred; however, you can sometimes change the PREFIX ("B") and see if you can find other parts.
http://www.shopjimmy.com/catalogsear...?q=BN94-01797A

It looks to be a common fault for this model. Boards are very hard to find. Maybe you can find someone nearby with the same TV with a cracked screen.

[Kridian]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

Thanks. Will go on a hunt.

[Kridian]

Yeeeaaar!


After going on a hunt through the Badcaps.net forums with people that had similar issues with their Samsungs, I jumped off into a YouTube channel where two of the responses where to Reflow the Main Board.

That did the trick! On the Main Board, I ran a heat gun for 60 seconds on the connectors for the LVDS cable and on the chip with the big heat sink (bottom of board). I was kind of shocked that it came on.

Just want to thank you Tom66 for your guidance on this project. And CashKennedy & Mt.Man for responding too.

[tom66]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

I'm glad it is working; at least you have pinpointed the problem down to the main board. Did you use flux on the main processor? Sometimes reflows work better with flux.

[Kridian]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

No but that sounds like a good idea. I just did the heat gun for a minute using aluminum tinfoil in a funnel-shape to keep other adjacent parts from getting the heat.

TV turned on normally this morning so I'm happy. Have to cherish the small victories.

[tom66]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

Leave four screws in it for now and test it for about a week, but it seems like you sorted it.

[Kridian]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

Celebrated too soon.

From a cold start, the TV will show vertical noise in blue or green (see pic) and then turn itself off, then back on as if it's trying to fix itself. Around 3 or 4 tries is when a normal picture will come on.

I re-soldered the connections this time on the LVDS & other connectors on the Main Board. Didn't help. I'm wondering if the heat I put to the Chip area was what turned this on?

I also updated the firmware from a usb thumb drive. Oh well.

My symptoms are exactly like in the YouTube channel, but mine doesn't take that long to turn on (instant).

[tom66]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

I'm about 90% confident your used "new" main board is bad, though you can rule out the control board with the test pattern jumper.

[Kridian]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

I'm about 90% confident your used "new" main board is bad, though you can rule out the control board with the test pattern jumper.

It's the original Main Board in there with all the tweaks I did to it. I can't really do any quick tests anymore as the TV is now at the owner's place so he'll have to put up with it for now. Will ponder some more on this.

[Kridian]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

I'm about 90% confident your used "new" main board is bad...

Indeed!

Just laying this project to sleep:
New Main Board was purchased and it turned on without a hiccup. Part # BN94-01797D was the available replacement.

*Really wish I could've salvaged the original.*

[mottes]

Re: Samsung PN50A530S2F Plasma Clicking power supply

Hello everyone,

I just picked up a samsung plasma (hpt4264) on craigslist for free because it has been experiencing the "click of death". I did some research already and many people said that a blown capacitor is probably the problem. So I took apart the TV but all the capacitors look pretty good to me (no bulging or leaking). The clicking noise is definitely coming from the power supply and I noticed that it also looks like one capacitor was already replaced, but I tested it with a multimeter and the rating seems fine. I tested a few other capacitors and they either read a number within 10% of their uf rating or some of them read a rating almost double (not sure if that means I'm doing something wrong or they could be bad.) The clicking is definitely coming from the power supply unit and the symptoms aren't exactly the same as everyone elses. What happens is the TV will turn on after a few hours rest but will then shutdown and start clicking after a minute or two. It is then impossible to turn the TV on until you give it another rest. The clicking is also 100% coming from the power supply. I am also attaching pictures of the psu. PLEASE HELP!

[koolkat68]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

I have a Samsung tv 50" plasma model Pn50a530s2f. When I turn it on the screen goes green with lines, stays like that for about 20 sec, then does a reset and the picture is fine.

[tvtimmy]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

You have a bad 47uf 10v capacitor on the back of the mainboard at c102.

[koolkat68]

Re: Samsung PN50A530S2F Plasma Clicking Transformer BS

OK Thanks I will look at that.