Samsung s42ax-xb01

[Mako]

Hi Im new to this forum, I was searching all over and this site kept popping up, but I couldnt not find anything pertaining directly to my exact model and problem. Ok, so this t.v. was given to us for free, and I used to fix some electronics that were trash, but havent done it in years. When I popped the back off of this thing, I barely recognized anything, and realized I was way out of my league alone on this. When I plug it in, the blue led light blinks 4 times, the melody plays, and blinks for the 5th time and stays glowing forever. Just as the led light blinks and stays on the 5th time, the screen starts to brighten but then dies instantly, but the led stays on. The buttons on the bottom work, but do nothing on the screen. I unplugged the Y board, and I am able to turn it on, with no picture. Same with the X board, and neither of them. So I can turn it on with one, the other, or both Y and X boards unplugged from the main board. Never get any picture though. I do not have a remote, and seeing as this is a nice TV, I am willing to invest a couple hundred into it if I can get it going again, without a repairman and their hidden fee crap. Any idea's? Also let me know if i should take any other pictures, anything I can do, I will. Thank you.

[Mako]

Re: Samsung s42ax-xb01

i followed instructions in another thread, by taking notes while testing the y and x boards separately. when i leave x plugged in, and unplug the y board, then plug it in, it clicks, the led blinks 5 times, then doesnt glow at all. i press the power button, the melody plays (sounds more like its shutting off), then the led light just stays on. the left side heat sinks on the x board get warm after a few minutes. i can do this a few times back and forth, it seems like the tv is powering on and off, but either way, the fans arent going. when i plug the y board in, and unplug the x, its far less interesting. it clicks, blinks 3 times, then the led stays on. also earlier in the day i tried simply changing the fuses, but they were all still good anyway. please any help would be very appreciated.

[tom66]

Re: Samsung s42ax-xb01

I'm pretty sure that on Samsung's older plasmas when they are in standby the LED glows blue, when they are powered on, the LED switches off. Don't ask me why.

You have a failed Y-Main or buffer board. It's a pretty common failure.

[Mako]

Re: Samsung s42ax-xb01

are you 100% sure? i found both parts online, and together its under 150$. i have a friend who is "so-so" with soldering, but i have worked with electronics my whole life, and know what to touch and what not to touch. would a couple of beginner-amateurs be able to fix this with the required parts? would it be worth it(aka will it break in a month) and it looks like it has 2 buffer boards on top. sorry if i sound like an idiot bt my knowledge is very limited when it comes to new stuff. so its stuck in standby?

[tom66]

Re: Samsung s42ax-xb01

S42AX-XB01 sounds like a plasma panel module, not the TV itself. A model number for a North American plasma TV like yours would be either HPT-xxxx or PNxx[A-Z]xxx. Can you show me a picture of the back label? I can then look up the user manual which will tell us what the LED should do.

IMO, $150 is too much for an old, 480p plasma, which, looking at the design, this most likely is. I can pick up similar working 480p plasmaas for less than £40 (approx $65) where I am, and get them for less than £5 broken on eBay.

[Mako]

Re: Samsung s42ax-xb01

wow 65? ok, ill take a couple more pictures. when the screen starts to light up, it also looks kind of...blotchy maybe? like spotty. my mother got it from someone she works with, and it was in the car overnight, on its screen. did this damage it at all? i took a flashlight to it in pitch black, and no cracks, only a minor scratch.

[Mako]

Re: Samsung s42ax-xb01

Hp - p4261
type no. Mz42s4

[tom66]

Re: Samsung s42ax-xb01

"when the screen starts to light up, it also looks kind of...blotchy maybe?"

This isn't damage to the plasma panel, but it indicates the X-Main is definitely the fault.

It will look a little like a lava lamp that hasn't quite warmed up if the X-Main fails, some parts of the picture will not light up properly, and the picture will be slow to respond to motion.

Often looks like this:
https://www.youtube.com/watch?v=Oea9vnTurCA

N.B. Z-Sustain = LG terminology, X-Main is the same for a Samsung.

[Mako]

Re: Samsung s42ax-xb01

you are good at this i must say. so firt you said y sus and/or buffer board, which there seem sto be 2 of? now its the x main? is there any way we can further diagnose this?

[tom66]

Re: Samsung s42ax-xb01

Well after you said you had any image (doesn't matter bad or good) it ruled out the Y-Main and your symptoms describe an X-Main fault.

Without an oscilloscope you can't conclusively declare the X-Main as being bad. It all depends on what you're willing to sink into it. There's a fuse on it. A good start would be to replace that. If the TV either refuses to power up or that fuse blows again we can check the X-Main. There are several transistors on it which can fail short circuit.

I've done two Samsung plasmas so far, and am working on the third right now. Two X-Main faults, and one Y-Main so far.

[Mako]

Re: Samsung s42ax-xb01

http://www.ebay.com/itm/SAMSUNG-HP-P...-/190714891003


http://www.shopjimmy.com/samsung-lj9...main-board.htm


http://www.shopjimmy.com/samsung-lj9...ffer-board.htm


are these the correct parts? would i likely have a working tv after these parts were installed?

[Mako]

Re: Samsung s42ax-xb01

ok, just saw your last. like i said, i tried all three fuses i could find in a stereo reciever i have, and it powered up and worked fine with each of the 3 fuses, i couldnt tell by looking at them since they are opaque. the fuses all work.

[tom66]

Re: Samsung s42ax-xb01

The first one is all you should need.

[Mako]

Re: Samsung s42ax-xb01

that would be absolutely wonderful, but it seems wierd. when only the x board is plugged in, the tv stays on, turns off, (no picture but it stays on). and when the y board is plugged in, alone or paired, the tv will not turn on at all. (the led being OFF when the tv is ON was very imformative thank you).

[tom66]

Re: Samsung s42ax-xb01

So let me get this straight:
X-Main unplugged (Y-Main connected): Weird blotchy picture but works fine otherwise
Y-Main unplugged (X-Main connected): Doesn't power up
?

[Mako]

Re: Samsung s42ax-xb01

Y- unplugged - turns on, zero picture whatsoever, but stays on (heat sinks on left side of x board get warm).
BOTH plugged in, tv turns on with blotchy image for 1-2 seconds, then shuts off.
x unplugged, y plugged in, it clicks, blinks 3 times, then led stays on.


-this is strange because ealier with both plugged in it would just constantly glow the led light, no matter what buttons i pressed.

[tom66]

Re: Samsung s42ax-xb01

Hmm the symptoms match the X-Main but it seems more like the power supply has some issues.
Got a DMM (multimeter?)
Bed time, talk tomorrow...

[Mako]

Re: Samsung s42ax-xb01

what is a DMM? and i will be on a few hours before i was tonight. goodnight, and thanks.

[Mako]

Re: Samsung s42ax-xb01

hey, are we ready to get going?

[Mako]

Re: Samsung s42ax-xb01

i can retest everything if it will help, and if you can tell me what dmm stands for exactly, i can probably borrow one tonight.