Hanns-G HG281D, LCD Monitor no power

[TioHerni]

Re: Hanns-G HG281D, LCD Monitor no power

Hello hello.

My HG281D monitor is also from 2009, and it has been suffering for a year now every time I want to turn it on after being turned off for a long time (or all night), but with patience it ends up working without problems once turned on. There are times that it even paints a blue vertical line, but after a short time it ends up disappearing.

Reading the different messages, I was going to try to change the following capacitors:

From power supply:
* C603 (22µ/35V)
* C606 (1µ/100V)
* C707 (22µ/35V)

From the control board:
* C080 (100µ / 16V)
* C083 (100µ / 16V)

What I don't know very well are the types, do they all have to be of the "Aluminum Electrolytic Capacitor" type?

Would you recommend changing any more than what I have indicated? I will receive more than necessary of each type because the packs they sell are usually a minimum of 10 or 20 units.
And if they have to be of other values, no problem, I buy them.

Thanks in advance,
TioHerni

[Recycler]

Re: Hanns-G HG281D, LCD Monitor no power

Well OK, I'm back here, the topic where I once posted, years ago.
My HG281D monitor is from 2009, and until this day I'm still using it. Sitting in front of it right now as we speak.

Over the years I have done several repairs.
The logic board was completely recapped. The power supply had to be done TWICE, as some of the caps were bad quality.
I now use Rubycon, Nichicon, Jamicon or United Chemicon, in that order.
It is a lot better.

I have never bought actual caps. Anyway, where I live it is impossible to get some quality stuff.
So I used exclusively salvaged caps (and all the rest I need) from old, broken equipment.
Did you ever find those Nichicon caps on a 25 year old PCB? They measure even better than new caps! The sheer happiness!

The power supply is simple and easy to fix.
I changed out the main cap 180 uf/400v for a 220uf/400 one.
I had the NTC at the AC entrance cracked, hard to find at first but once it cracked completely it was quickly replaced.

The 5 volt power supply (for standby and logic board) also blew up once.
I replaced the mosfet 04N70 with 06N60 (seems OK) and also the SMD zener diode nearby, that is some kind of protection. I used a normal 18v zener diode.

It's funny the CCFL's are still going. Also, I have never touched the inverter board because there was no need.
Inside of the panel, some little plastic clips broke off and fell down. I turned the monitor a bit so it moved to the corner as it leaves a tiny dark spot, that is now in the lower right corner.

All in all, this must be the longest running monitor I've had during my 30 years in IT.

Cheers.

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

I have read that the most changed have been the C80 and the C83, both 16V 100uF, but also recommendations to change others, such as the C74, C77, C8, C13, and the C14, but I cannot see their values to ask for the same.

If you have the PM549DA3 main/logic board, see the list of caps mentioned here:
https://www.badcaps.net/forum/showpo...&postcount=842

Going by that, most of the small caps should be 16V 10 uF... but just order 50V 10 uF, as those are easier to find in low ESR and are physically bigger (so can handle more ripple current and thus should last longer in a hot LCD.) According to that list, there are 3x 470 uF caps as well.

Q601 appears to be part of the PSU board, I think, as shown here:
https://www.badcaps.net/forum/attach...2&d=1291157414

It probably has been running hot due to bad caps on the PSU board. But it might still be OK. You can buy a spare, but don't replace it just yet until you finish the recap. There's a good chance it should be OK after the recap.

In regards to recapping the PSU board...
- If you have a PSM217-404-H-R board, see these two links:
https://www.badcaps.net/forum/attach...2&d=1341463821
https://www.badcaps.net/forum/showpo...&postcount=842

In particular, replace all of the small caps under 470 uF. Leave the 470 uF and bigger caps alone, as those are probably UCC brand and should still be OK (unless you can find equivalent replacement Japanese caps.) It's the smaller ones that tend to dry out in a hot PSU.

[TioHerni]

Re: Hanns-G HG281D, LCD Monitor no power

Q601 - df - 2sd1898

Thanks Lotas

[lotas]

Re: Hanns-G HG281D, LCD Monitor no power

Q601 - df - 2sd1898

[TioHerni]

Re: Hanns-G HG281D, LCD Monitor no power

Hello, hello, mine is already 15 years old, and since the last year it's already having a hard time turning on, sometimes I have to turn it on and off many times until it stays on for more than 30 seconds, but once that time is reached It does not turn off.

Sometimes it also paints a blue vertical stripe on the left 25%, but it ends up disappearing after a few minutes, I don't know if it has any relation to this with the capacitors.

Also, if I leave it in sleep mode, the yellow led in the bottom right corner blinks at different rates.

I found this thread 10 months ago, and I've finally found time to take a look at it on an electronic level.

I'm trying to make a list of all the possible capacitors I could change to make the complete order, because I don't have any electronics stores nearby and I want to avoid multiple trips.

I have read that the most changed have been the C80 and the C83, both 16V 100uF, but also recommendations to change others, such as the C74, C77, C8, C13, and the C14, but I cannot see their values to ask for the same.

They also said to change the "green" capacitors and I'm in the same situation, I don't see their values to buy them the same.

And also, if someone can tell me if I should also change this component, labeled as "O601" (attached image) that I see as burned on the power board, and which component is to order it too.

Thank you very much everyone, and good luck with those repairs.

[7thSenpai]

Re: Hanns-G HG281D, LCD Monitor no power

Thanks all!

I've had this monitor in my closet for ages and always liked it but couldn't make myself to throw it out. I vowed to someday to at least attempt to fix it. So now after maybe 6 years or so I decided to venture into electronics and learnt a bit, got myself some basic tools and my prized scope for a hobbist..

I have replaced C80 and C83, also few on the PS with caps on hand. It seems to be working. Although after reading what momaka said I might wait for caps to do the whole logic board then put everything back together. And I did also partially damaged some pads that got lifted, just be aware fore new people. The pads do seem very fragile then most..

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

about 18 months ago I think I replaced 2 caps, which solved the problem of my screen going black after a while. Now the problem is back. It appears mostly when browsing websites with lots of dark colors/backgrounds. Once it starts, the only solution is to turn the monitor off and leave it off for half an hour or so. Then it works fine. Suggestions with links to what to replace will be appreciated. Thanks!

What capacitors (brand and series) did you use and where did you buy them from?

Also, I'm guessing you just replaced C80 and C83 on the logic board, as outlined here?

If so, you may want to replace the rest of the small caps on that logic board as well - in particular, not only C80 and C83, but also C74, C77, C8, C13, and C14. For the 100 uF caps, you can use 220 uF caps, and for the 10 uF ones, I think 22 and/or 47 uF would be OK too, if those are easier to find.

If that doesn't fix the issue, it may also be time to recap the PSU. Hard to say without some pictures, though. In any case, I do recommend people do a full recap at least on the logic board and not just C80 & C83.

[unigroove]

Re: Hanns-G HG281D, LCD Monitor no power

Hi all,

Great topic that has helped me fix my HG281D before. about 18 months ago I think I replaced 2 caps, which solved the problem of my screen going black after a while. Now the problem is back. It appears mostly when browsing websites with lots of dark colors/backgrounds. Once it starts, the only solution is to turn the monitor off and leave it off for half an hour or so. Then it works fine. Suggestions with links to what to replace will be appreciated. Thanks!

[Cubensia]

Re: Hanns-G HG281D, LCD Monitor no power

Hello
I just save my HG281D yesterday changing all CAPS of the power board except the big one ( the only one i found was a 120µf 450, but way to huge ).

Thank's to this usefull guide thread

[gordesky1]

Re: Hanns-G HG281D, LCD Monitor no power

hmm so i seen this guy post about the red blue and green colors what im getting always now.

post 838 a page back.

Hello
I have a screen hg281d down.
At the start, it cycle on red blue green.
I replace c80 & C83.
I do not have 1.8V to regulator vs18.
The output is short-circuited with ground.
The regulator is ok, the capacitor is ok.
I do not have the schema to find or is short circuit.
If anyone had the schema.


This is c82 was hs.
thanks.
now the screen turns on but there are red dots everywhere.
The tensions are good.
An idea?


thing is i dont see anything on c82??? just 2 solder joints. unless im missing something?

[gordesky1]

Re: Hanns-G HG281D, LCD Monitor no power

just posted this issue. Figure i post it here too incase any of you know what can be the issue. https://www.badcaps.net/forum/showthread.php?t=89422

[salftrash]

Re: Hanns-G HG281D, LCD Monitor no power

quick reply ive fixed several of these over the years. they were widely available as black friday special. a few caps (all the same ) blew on each one. replacing was faster than disassembly. been fine since, more than 1 year

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

Btw im replacing caps from pc motherboards, cause cant afford japanese right now, and for sale in local shops only chinese.

That's usually fine. I do the same myself quite often. As long as the used caps are of good quality brand, they should be okay to reuse in most cases.

No-name Chinese/Taiwanese caps (or known brands, for that matter... like CapXon, ChengX, Chong, etc.) are usually a waste of time and money anyways.

After replacing 5 caps totally nothing changed. Ill try get somewhere more good caps, and maybe its helps.

You need to replace the caps mention on your PSU board as well. And possibly look for anything that might be off or wrong from the previous repair shops' work. That diode on the bottom sure is a dodgy repair job. I don't recommend going to that repair shop anymore. You can probably do a better repair yourself with the help of BCN than that.

And i have one question about logic board. There is processor, how to test him?

Simply put, you can't. You can only check the voltage going to it and maybe see if it issues the proper turn-on signals. But apart from that, anything else will be very hard to do and require specialized expensive equipment that even more sophisticated repair shops won't have.

Speaking of the processor...

My teacher from service center says problem could be just in proc, so nothing will help anymore and just getting new board. But he honestly says, he not really good in displays.

The processors in these monitors almost never go bad. Typically, only a lightning strike or severe ESD shock can kill them. So personally, I think it's very unlikely that the processor on your board is bad. More likely, you have a combination of bad caps and possibly some bad solder joints, dirty cables, and maybe shady work done by a previous repair shop. (Check all cables and make sure they are all seated well. Also, check for any "ghetto" modifications and repairs.)

Idk who placed diode, displays was on repair in 3 different. As my teacher said, it for force power on.

That's fine to do as a "test" on the power supply. But for a repair shop to return the power supply like that to you, I'd say they're close to incompetent (at least when it comes to LCD repair).

The circuit should work as it was intended. Removing that diode and restoring whatever circuit there was originally would be a good second step in troubleshooting, after changing all the necessary capacitors.

Changing "16V 100uF" to "16V 220uF" or "10V 220uF to 16V 220uF" is ok? I have seen in this thread, but forgot the rule. I should keep V but can increase uF? Or Keep uF and increase V slightly? Im not banned in Google, but wanna ask here.

It should be fine either way, actually, since these caps are filtering linear regulators.
But more precisely, the rule is: keep capacitance the same or within 25% of the original (preferably on the high side rather than under) and keep voltage the same or higher (that is, if you don't know what the circuit voltage is.)

[imindf]

Re: Hanns-G HG281D, LCD Monitor no power

Currently i have replaced 5 caps, two most reccomended C80 & C83. I placed there 16V 220uF, with 0.00 ESR. Still not understood for sure what is ESR, but think 0.00 is good, and if more than maximum as an table says this capacitor bad. Btw im replacing caps from pc motherboards, cause cant afford japanese right now, and for sale in local shops only chinese. After replacing 5 caps totally nothing changed. Ill try get somewhere more good caps, and maybe its helps.
And i have one question about logic board. There is processor, how to test him? My teacher from service center says problem could be just in proc, so nothing will help anymore and just getting new board. But he honestly says, he not really good in displays. Is there ways to check CPU health?
Also tried to connect to Orange Pi, maybe another signal... but no.
And i forgot to say something, maybe important. Last time i connected smartphone with mini-HDMI, to check how it works. After few minutes of looking how its hard to play movie with low Hz 1 core cpu i deattach. And display didnt worked anymore after this.

Thanks for assisting, momaka. Few your links already in bookmarks, very helpful.

Idk who placed diode, displays was on repair in 3 different. As my teacher said, it for force power on.

Changing "16V 100uF" to "16V 220uF" or "10V 220uF to 16V 220uF" is ok? I have seen in this thread, but forgot the rule. I should keep V but can increase uF? Or Keep uF and increase V slightly? Im not banned in Google, but wanna ask here.

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

If changing capacitors to quality japanese could bring life for ~5 years it would be fine. But before invest i wanna to be sure that this will solve problem. Im not sure, is it about just some bad caps, or something new. Im novice to electronics, just studying in service center and trying to fix everything for getting experienced.

Hi imindf, welcome to the BCN forums!

It is hard to say with 100% confidence that new capacitors will fix your issue. But given how many problems these monitors have with capacitors, replacing them would be the first basic step in troubleshooting. Reason for that is because when you have bad capacitors in a circuit, they can cause other circuits to misbehave down the line. And then you wouldn't know why that is happening and probably never find the fault.

So as a first step, recap the video/logic board on the monitor and also all of the small capacitors on the PSU board. I think the larger capacitors on the PSU board are United Chemicon KY or KZE (if I remember correctly), which shouldn't need replacing if they are that. But all of the small caps will likely be dry at this age now.

Regarding the recap, see this:
https://www.badcaps.net/forum/showpo...&postcount=827
and this:
https://www.badcaps.net/forum/attach...8&d=1435812326

And one more picture that may be useful:
https://www.badcaps.net/forum/attach...6&d=1351012349

And one more question. I have empty slot on power supply. Is it normally? Image attached, with red circle painted.

According to some pictures I found in this thread... namely these three:
https://www.badcaps.net/forum/attach...2&d=1291157414
https://www.badcaps.net/forum/attach...5&d=1331360444
https://www.badcaps.net/forum/attach...9&d=1415717806
... it appears that the missing connection there in normal. Looking at the PSU deisgnators, you can see that connector has 4 pins: 2 labeled with "GND" and two with "+12V". So, it's probably not needed.

On the other hand, this picture shows all cables connected:
https://www.badcaps.net/forum/attach...9&d=1358649456
But honestly, I don't think the logic board uses 12V (except possibly for the audio amp... though if you are already getting audio through, then the audio amp is powered from something else, obviously.)

Also, do you know who put that diode there on the bottom right next to where you circled the area in red? (It's North of the circle.) Was that done by one of the repair shops? If so, I wonder why.

[imindf]

Re: Hanns-G HG281D, LCD Monitor no power

According to my previous post, didnt attached correctly.

[imindf]

Re: Hanns-G HG281D, LCD Monitor no power

Greetings everyone! Glad to find this thread with almost 50 pages about our monitor. Wonderful, how many customers got same trouble with this good and bad build at same time. I had to read many pages but im not found my current trouble, or im just misunderstood something.
Previously i had after ~2 years of using trouble with image artifacts, im not sure how to write about them, think u saw these lines and dots ^^. Fixed in service center where it was bought.
Next my HG281D had troubles when i power on him, time to prepare was increasing till totally not powering on (or i just didnt waited for 1-2 days). Like old monochrome TV... This was fixed for not very long time, and happens again with same defect. Fixed, but just for around 50 working sessions. (Used it rarely, cause got another monitor)

Ok, but now i have something new, and cant find solved same symptoms.
Its turning on, black color of display changes to black image. Previously it was white or gray, but after re-soldering 3.3V it has changed to black.
Indicator of power is blue, like it working normally.
Sounds is ok music work.
Plugging to laptop and even w/o AC my laptos says about connected device HannsG.
After 2 hours of laying on table with matrix down it become very hot, almost harms. I forgot how normally its or not.

If changing capacitors to quality japanese could bring life for ~5 years it would be fine. But before invest i wanna to be sure that this will solve problem. Im not sure, is it about just some bad caps, or something new. Im novice to electronics, just studying in service center and trying to fix everything for getting experienced.

Hope i writed enough well to understand my globish skillz

And my config is:
PM549DA3 M06 VER6.0 logic board
PSM217-404-H-R REV A.1 power supply

And one more question. I have empty slot on power supply. Is it normally? Image attached, with red circle painted.

[gordesky1]

Re: Hanns-G HG281D, LCD Monitor no power

Whoops sorry about just putting a link for the pic. Didn't see the manage attachments on my first post... But yea as you can see by that solder point that's were it got shorted at and around that area had black on it but it cleaned up fine but did melt the solder by that joint which im hopeing didn't cause any damage... The fuse went out really fast tho probably in a sec and than it lost power. That's were the lcd inverted connector hit and melted some of the connector too but seems like ony the metal part sense the wires and connections look fine on it.

I would order one of those psu cap kits for the psu and also a new fuse but just worried if it cause any more damage:/

[gordesky1]

Re: Hanns-G HG281D, LCD Monitor no power

So my monitor died back in july when a power outage happen right after it refused too power on no power light at all.. So i sat it aside till today and took it apart.

Tested the fused first and that tested fine and i noticed when apart sometimes i can get it too turn on but the light will come on the screen will also come on than go out 2secs later and repeats and than dies and its hard too get it too do it again..

Than something stupid happen... The inverted cable hit the power supply on the back of it and a big spark happen and i get no power at all from the psu...

Tested the fused and yep its blown.... it also left burnt spot in that area too which is by the fuse.. Now i wonder if its even worth it anymore? Heres a pic. I cleaned it up which came fine but as you can see its missing some solder on the joint of carli mpx40/100/21 yellow cap tho it might be fine tho.

http://prntscr.com/mweq7o

I was going too see if i can replace the C603,606 and 707 caps as Mishannya did with his cause he had no light either. And probably going too need a t4.0a250v Brown square fuse.... Now the other thing it did burn the video connector some but it didn't touch the metal contacts just burn some plastic.. Oh is it possible too just jump it with a wire for the fuse for now too see if the powersupply at least powers up?


Oh forgot too add back in 2014 which i also posted on this site i had too replace c80 and c83 on the main board cause the buttons was wacky and i couldn't adjust the brightness or anything and sometimes the screen would go on and off. But the blue light always stayed on. So the problem im having would be related too the psu caps now?