Hanns-G HG281D, LCD Monitor no power

[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!

[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.

[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..

[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.

[lotas]

Re: Hanns-G HG281D, LCD Monitor no power

Q601 - df - 2sd1898

[TioHerni]

Re: Hanns-G HG281D, LCD Monitor no power

Q601 - df - 2sd1898

Thanks Lotas

[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.

[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.

[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