I would think, and I do hope that there's someone here who has access to some kind of technical information on Viewpia LCD TV's, particularly their 26 inch and larger models.

These TV's are sold over in the UK and europe, and they have a few things that can go wrong. Of particular interest to me is the failing to come out of standby, and the LED on the TV's front becoming very dim. I've searched on google for hours, and all i have found is people with questions, and no relevant answers.

I'm also trying to figure out how to access the service menu on a Viewpia LCD TV. The EURAS database seems to hold some answers for me, but of course I can't access it.

If anyone can provide me with any technical information, I would be very grateful.

000

The first thing I would do is check the power supply for failing caps.

Trust me it ain't the power supply. That was my first guess, but swapping power supplies with a known good one does not fix the problem, but swapping the chassis board fixes it.

Also, even the worst new bad caps usually don't fail for at least a few months, these TV's could fail within a week.

Check the surface-mount caps on the control board, SMD caps tend to get baked dry in LCD's. Also does this thing have a combo inverter/PSU board, or are they separate boards?

Sorry, but I need actual technical information on this brand. I would love to take guesses at what's failing and troubleshoot with test equipment, but time constraints prohibit me from doing this.

And yes, it has a combo invertor/PSU board, but again the power supply is fine. Once the chassis board is replaced with a known good one, the TV has no more issues. The power supply powers it just fine.

The issue lies on the chassis board.

Does this set have a large IC on the control board with no pins sticking out of the side? If it does, these are called ball grid array chips. If you look under the IC you can see the tiny solder balls but nothing can get to them. The heat from the IC can cause the no lead solder to crack and cause many problems. I have inquired as to repairing these and gotten some wild suggestions. I tried a heat gun and it fried the chip. Another that worked was to put the board in an oven at 400 degrees for around 15 minutes and that is supposd to reflow the solder. It has actually worked about 30% of the time.
The biggest problem is melting the plastic connectors.
ROHS.... designed with difficulty in mind!

000

Well, ANY technical information I can find out about these TV's will be of great use to me.

I'll level with you guys... I know more about these Viewpia sets then most of their customers overseas do. I know because where I work sells what are essentially these same TV's, only with our logo and a different casing. I found out about Viewpia through a goof up where one of our TV's had the user guide for a Viewpia in it

Now you would think we could just get all the technical info we needed straight from the manufacturer that makes these TV's for us... if you think that, you've never dealt with a Chinese TV manufacturer. Those assholes won't even give us the time of day, so we're on our own for technical info.

Does this set have a large IC on the control board with no pins sticking out of the side? If it does, these are called ball grid array chips. If you look under the IC you can see the tiny solder balls but nothing can get to them. The heat from the IC can cause the no lead solder to crack and cause many problems.

Oh yeah, these chassis boards have BGA chips on them... My mistake. These do NOT have BGA chips in them.

post pics of the boardset.
seems this set is sold under several names like spectroniq,ect

This is the chassis board.

http://i33.tinypic.com/212d6he.jpg

The problem lies somewhere on this board. I just don't know where.

Any ideas? Anyone?

With as many surface mount parts it has, you might have to replace the board. Those 'lytics could be changed easy enough but the rest is not so easy. Ever tried hand soldering SMPs? Not fun at all. :no: The chips are impossible when the pins are so close together that there's only about .10 of an inch between them. There probably is a bad chip there somewhere too. Usually what goes on this kind of stuff. I guess in other words, check and replace what you can without wasting too much money on it. Good luck with it. :yes:

With as many surface mount parts it has, you might have to replace the board. Those 'lytics could be changed easy enough but the rest is not so easy. Ever tried hand soldering SMPs? Not fun at all. :no: The chips are impossible when the pins are so close together that there's only about .10 of an inch between them. There probably is a bad chip there somewhere too. Usually what goes on this kind of stuff. I guess in other words, check and replace what you can without wasting too much money on it. Good luck with it. :yes:

Here's the deal. This is not just one TV. It's hundreds. Finding a solution will fix at least 10 of these right now.

I also found out today that these TVs are also sold by Pyle.

Just reviewed the entire thread.

You state -

Country of origin - China
Sets fail within a week
Hundreds of sets affected

OK - I'll be a smart a** - why bother with them???

Even if you were able to solve this particular problem, the re-failure rate of these sets has to be astronomically high.

ive seen that exact controller IC used in numerous other LCD sets that I have worked on. its even heatsinked. the failure rate of that CPU control IC is low... so low that it isnt evne possible, however the vizios use the same IC and they DONT have a heatsink, but i find them failing an alarming rate becuase of lack of a heatsink, proper heatsinking problem never shows up.

In your case, i would vote out the main IC. what you need to do is monitor the on-board boost/buck switching regulators that pump out the proper core voltages for shorts and/or proper voltages. standby light is probably dim because there is a short in the rail on that main control module. ive delt with a couple of other brands with similar issues, and it turned out to be core regulator output transistors had failed.

keep an eye on these. And im also sure it goes without saying, in standby mode, check for excessive heating of any transistor, and obviously the CPU core. if the CPu gets abnormally hot then your done, only solution is to replace the board unless you can find a supplier in china for the IC, and usually these ICs have custom programming stored on the IC itself so your chances for that are none... And check your class-D audio output circuits for rail loading.

000

Just reviewed the entire thread.

You state -

Country of origin - China
Sets fail within a week
Hundreds of sets affected

OK - I'll be a smart a** - why bother with them???



No choice in the matter. I won't get into why that is, but we're stuck with the damn things and we have to sell em.

I know they're crap. There's nothing i can do about it except try to track down the causes of failure.

ive seen that exact controller IC used in numerous other LCD sets that I have worked on. its even heatsinked. the failure rate of that CPU control IC is low... so low that it isnt evne possible, however the vizios use the same IC and they DONT have a heatsink, but i find them failing an alarming rate becuase of lack of a heatsink, proper heatsinking problem never shows up.

In your case, i would vote out the main IC. what you need to do is monitor the on-board boost/buck switching regulators that pump out the proper core voltages for shorts and/or proper voltages. standby light is probably dim because there is a short in the rail on that main control module. ive delt with a couple of other brands with similar issues, and it turned out to be core regulator output transistors had failed.

keep an eye on these. And im also sure it goes without saying, in standby mode, check for excessive heating of any transistor, and obviously the CPU core. if the CPu gets abnormally hot then your done, only solution is to replace the board unless you can find a supplier in china for the IC, and usually these ICs have custom programming stored on the IC itself so your chances for that are none... And check your class-D audio output circuits for rail loading.


Glad I can rule out the IC.

We had one TV work intermittently. It displayed this same symptom, then fixed itself, then died again.

Could you perhaps point out the transistors you are talking about?

Okay, so the plan now is to check for shorted transistors.

Any luck on getting any technical info, like, oh how to access the service menu on these things?

See, the idiots who programmed these, most are all right, but about 10% of them either have the color set way too high, or the LED backlight set too low, or some other screw up that might require a firmware update (as if I could get ahold of that), but may be fixable in the service menu... if I could access the damn service menu...

000

If it's intermittent, then I'd just about bet my life on bad soldering. Shorted transistors, and blown ICs don't fix them selves. It could also be a firmware bug that's causing problems (eg. corrupted NVRAM locking up the micro controller). I fixed one LCD TV with badly distorted video by reprogramming the settings EEPROM from the one in a good set.

Bad soldering was my first guess, but I've looked all over for bad soldering, and touched up numerous solder connections that were fine to begin with. It's not a huge board, but there are so many solder connections... and bad soldering would lead to a host of other issues. Apart from this one issue, these TV's have nothing else wrong with them, apart from the occasional TV with programming issues.

The TV's that work, work just fine. We have two being used here as computer monitors. They're left on all day long. We've been using them for a couple months with no issues. It seems that if one of these TV's can make it past 2 or 3 weeks, then the chances of it failing drop drastically.

These TV's are all failing in the same way. This tells me that the failure is occurring in the same area, and maybe the same component or solder connection. Only one TV so far displayed this intermittent behavior, out of maybe 15-20 that have just outright failed without any warning whatsoever.

By the way: If it will help, here is a high resolution picture of one of the dead chassis boards.

http://content.imagesocket.com/thumbs/highresboard729.jpg (http://imagesocket.com/view/highresboard729.jpg)

Is that a burn mark on the 8 pin IC just above the VGA connector?

if its intermittent, ill tell you what the problem is. soldering. period.... no matter what.

easiest way to resolder a flat-pack IC such as the micro, is take a thing of solder paste, the stuff you refrigerate, use a needle tip, put a tiny bead on all 4 sets of pins. then take a hot air rework station, about 25% air, 75% heat adjustment, and then take the smallest gun tip you have, like i do, and gradually blow toward and go down the set of pins. it will re-do solder on all pins, using a lighted magnafier, wick up any potential cross-over.

if you are going to repair any of these kinds of electronics, you must have a rework station, thats about the jest of it. and by looking at your high-res photo, i can see some cracking of the pins of the CPU because of the heat issue. plus its not a bad idea to reflow the DRAM IC.

Is that a burn mark on the 8 pin IC just above the VGA connector?

No. It's marker or paint of some type.

if its intermittent, ill tell you what the problem is. soldering. period.... no matter what.

easiest way to resolder a flat-pack IC such as the micro, is take a thing of solder paste, the stuff you refrigerate, use a needle tip, put a tiny bead on all 4 sets of pins. then take a hot air rework station, about 25% air, 75% heat adjustment, and then take the smallest gun tip you have, like i do, and gradually blow toward and go down the set of pins. it will re-do solder on all pins, using a lighted magnafier, wick up any potential cross-over.

if you are going to repair any of these kinds of electronics, you must have a rework station, thats about the jest of it. and by looking at your high-res photo, i can see some cracking of the pins of the CPU because of the heat issue. plus its not a bad idea to reflow the DRAM IC.

I have a soldering iron. That's it.

Also, it was intermittent on *one* tv... out of maybe 20 that have failed so far.

I have a soldering iron. That's it.

Also, it was intermittent on *one* tv... out of maybe 20 that have failed so far.

i understand that. but what i said still holds true.

i understand that. but what i said still holds true.

Okay. The heatsinked chip is a suspect for bad connections then?

The EURAS database has info on Viewpia models, and probably has the info I need, but I can't access the damn thing.

EURAS is free for like 30 days, well it used to be, also try here: [email protected] discussion

EURAS is free for like 30 days, well it used to be, also try here: [email protected] discussion

You need to be a registered repair company and have all kinds of certifications and blah blah blah.

But I'll check out your other link. Thanks.

hmm. never had to supply any of that information before. but the last time i used the site was in 2002 also.

I may or may not be of help here but I would monitor each section off the filter caps for voltage indifferences against a working one and one that is intermaiitant or failed. I know this may be diffucult considering the tv has to actually be powered up to do so but im under the impression that you sould check these units for inherent cooling issues when the board is in operation. Im one of those to think you may have a cold solder joint somewhere too. Have you tried holding down one or more buttons as you plug the tv in to see if you get a dim standby light? I know it sounds dumb but have you tried unplugging the button strip and power the set up via remote?

I know it sounds dumb but have you tried unplugging the button strip and power the set up via remote?

The problem is fixed by swapping the chassis board for a known good one, not swapping the button panel.

I'm going to hunt for cold solder joints probably tomorrow.

An update for you guys:

I'm now sure it's the heatsinked IC chip that's causing these to fail. I found one with definite bad solder connections, and if there's one...

Problem found, now just need a way to resolder these tiny tiny pins.

As i explained, use a hot air rework station with small tips plus some solder paste.

As i explained, use a hot air rework station with small tips plus some solder paste.

You're right, but I don't have one.

See, money and time come into play here. Christmas is coming, and things are getting busy, so I don't have hours to spend re soldering tiny pins with equipment that we don't have and that I have never used before.

What we'll probably end up doing is somehow forcing our friends in China to either step up their quality, or at least send us new boards.

Now that I know what to look for, I can at least let them know that we know.

Hm, those rework stations aren't that expensive. It's something I'll keep in mind. if the problem worsens, I may be able to convince them to get one.

There are also re-work stations with small conventional tips that you can use with small gauge solder. While I prefer the hot air, others I know prefer the tips. I think the prices are about the same.

John

Just using my soldering iron, I brought one of these boards (partly) back to life. the thing will power up and display video, but no audio.

I plan on using my finest soldering iron tip and see if I can bring another one back to life within the next few days.