Polaroid 42" TLX-04244B

[stevekasian]

Hi,

I copied this straight from a FixYa request page becasue it is my exact problem:

I have a Polaroid 42" TLX-04244B. When turning the power on the polaroid logo comes on for a sec. then screen goes black with the blue power LED staying solid. The red LED on board blinks once every 2 seconds.

Unfortunately there was no remedy posted for the poor guy.

In my case, I'm noticing that the image definitely disappears from the screen itself at the moment the backlight goes out, and that the speakers make a faint fading static sound at the same instant. Sometimes there are a few vertical lines on the left side of the screen as well, which are visible against the blue background of the Polaroid logo.

Taking pictures now and will post them shortly. In the mean time, if anyone recognises this symptom I would greatly appreciate your 2 cents on the matter. Thanks!

SK


Layout shots below. Close ups to come in next post. (Need to go out and buy batteries for the good camera first!!)

[Spitz]

Originally Posted by stevekasian

Hi,
I have a Polaroid 42" TLX-04244B. When turning the power on the polaroid logo comes on for a sec. then screen goes black with the blue power LED staying solid. The red LED on board blinks once every 2 seconds.
Taking pictures now and will post them shortly. In the mean time, if anyone recognises this symptom I would greatly appreciate your 2 cents on the matter.

Looking at the pictures, there are some bad caps on the main board on the left.
Hard to tell for sure, need more focused pictures.

[retiredcaps]

Post pictures of the inverter board with new clear focused pictures of the power and main board. The ones included are too fuzzy.

[stevekasian]

Finally got my batteries:

[stevekasian]

Additional information:

Before I pulled the boards, I disconnected the two HV plugs for the backlight and restarted the unit, as well as the audio amp section. The device still did the exact same thing. So I am pretty sure the problem is with one of the two boards pictured above.

[retiredcaps]

1) Hookup a working dvd player and cycle through the source button until hear sound. Now it is set to the correct source.

2) Power off the TV, but leave the dvd player running. Wait 5 minutes.

3) Power on TV. Do you see the dvd playing on the TV? If yes, does the backlight then go off 1 second later?

[stevekasian]

There is no sound. The video and sound both go into some sort of "off" mode. The light on the front is still a steady blue, but the LED on the power supply is flashing every 3 seconds.

When it "shuts down" after initial power up, as described in the first post, if I put my ear next to the power board i can hear it go "chink", as though there's a major release of magnetic field in the transformer(s). There are no relays though, so it's not a switch making that noise.

[retiredcaps]

On connector 3 of the power board, there is a legend with marked voltages. Start there to see what voltages are present/missing.

[stevekasian]

Unfortunately, due to the nature of the problem, the logic board needs to be wired up in order to get the unit to start up then shut down. And I can't check voltages on the pins while as they are plugged in because I don't have the facillity to bench test stuff with it all wired up, etc.

So I guess that pretty much leaves me in the lurch, huh? Is there any way to troubleshoot it at least somewhat without having it wired and powered up?

I realise that probably sounds weak, but unfortunately I just have very limited ability to test live circuits at present.

[Bunkyda]

Did you ever get this solved i have the same exact problem to "T"! Please Let me know.

[stevekasian]

Hi, Bunkyda...

I just ordered the power supply/inverter board (all in one) and will do the R&R in the 2nd week of June, when I get back home. I'll post back here then and give an update. I'm about 99% sure the problem is with the inverter transformer on the power board.

BTW... they are on sale right now for $84.12 on Shopjimmy (or at least they were when i bought mine), which is a steal for this board. U might want to pick one up now and hold onto it, just in case, as they are very hard to find @ under $100!

http://www.shopjimmy.com/polaroid-89...upply-unit.htm


Steve

[stevekasian]

Finally got back home and installed the board. The TV starts up!

BUT... I need some advice, as I have a bad feeling I have a ruined screen.

If y'all would be so kind as to take a look at my attached picts below and tell me what you think, I'd really appreciate it.

Thanks!
SK

[selldoor]

Check and Reseat all connectors especially the ones to the panel.
Do the lines stay on and in the same place and is it the same with a signal
Is the sound on?

Did it have this problem before it wouldnt come on or did you aquire it without seeing it on?

[budm]

Yes, do try to reset the LVDS cable to the panel, this a pain to get that cable back in place.

[stevekasian]

Hi - Thanks for the responses.

I acquired the TV with a faulty inverter transformer, so the backlight would only flash on for an instant. I do not know if it had the problem before - I never saw it before, but it's possible I just didn't notice it.

I can say that I never removed the TCON board at all, and I did try pressing on the TCON connectors at both ends of the LVDS cable while it was on (moving them around, juggling them, etc.) and there was no change.

The lines are in the same place each time I turn it on, regardless of what is displayed on the screen. They do sort of move around a bit when I press on the screen right on top of them. They can sort of disappear where I press on them and kind of "grow" a little further down (because most of the lines do not span the entire height of the screen, and therefore have an end to them... Sometimes those ends sort of elongate when I press on them, and the lines can kind of get little gaps in them where I pressed on them also.)

SK

[budm]

If that is the case, then you may have tab bonding problem on the LCD panel itself, not good news.

[stevekasian]

So it's the old tab bonding problem, eh? Well, I ran into that with another TV I was looking at buying, and I chose to pass on it due to the work involved. However, since I already own this one and have put time and $ into it, I'm willing to tackle it.

I won't be back home to do so until the Fall though, so it'll have to wait.

In the mean time, anyone else with any other suggestions please feel free to chime in; I'm entertaining all possibilities at this point. :-)

Thanks!
Steve

[stevekasian]

I'm back! And now I've got to figure out what to do with this TV...

Does anybody else here reading this have any experience with LCD screens having tab-bond issues, and maybe a more definitive affirmation as to whether or not the pictures I posted above are typical symptoms of a tab-bonding issue?

Just hoping to get a little more to go on before deciding whether or not to tear this thing down in the pursuit of possible wild geese!

Thanks,
Steve