Hanns-G HG281D, LCD Monitor no power

[selldoor]

Re: Hanns-G HG281D, LCD Monitor no power

Please can you delete your pictures and reload them using manage attachments

[jimmy1256]

Re: Hanns-G HG281D, LCD Monitor no power

OK. I've read all of the pages up to this point, even found the exact problem described that I have. Hanns-G 281D Rev.2. From a cold start the monitor turns on and works fine for about 3 minutes. Then black. LED indicates that its getting a signal from the computer. Using a flash light shows no image. Turn it off/on and I get the image back for about a second. So far I have replaced all of the caps on the power supply and the main board. No change. (probably not a cap issue) Not sure where to go next and am feeling a bit dejected that the caps didn't fix the problems. Any body have an idea what to do next?

Thanks for the replays to my original post. Sorry I didn't get back sooner. I was frustrated at this repair and the holidays didn't help either. Anyway, I disassembled the monitor again and checked for the voltages. go the 5.0 volt line but that is all I can get. There is not enough wire to keep everything plugged in and be able to reach to measure the voltages. I took pics of the boards here.




Any help is appreciated. Thank you.

[Castor8]

Re: Hanns-G HG281D, LCD Monitor no power

Power board:

I replaced all the caps what Lumberjack777 marked me on post #704.

Main/logic board:

The man (he was pro) replaced 3 caps (I think, I am not sure of it, because I did not see what was he's doing). Those on the pics looks new(Yageo - 100uF,16v, 105C all of them).

Finally:

I cleaned the lvds cable with Clin (window cleaner with alcohol).


Unfortunately I cannot test the voltages, because I do not have any instrument.

[selldoor]

Re: Hanns-G HG281D, LCD Monitor no power

It might help if you could say exactly what caps you eventually replaced on both boards
and what make series you used. I have re read it and still do not know what caps were
replaced on the power supply - just the two that looked bad or more?
When it is on can you test the voltages on the connector from power to main and do they remain steady. Also test the voltages on the 2 voltage regulators - again do they remain steady, and also the voltage across the the 2 caps near the voltage regulators that have just been replaced.

[Castor8]

Re: Hanns-G HG281D, LCD Monitor no power

I cleaned up the cable but it is still the same.

Anyone has any idea how could i fix it? It is not bothering me too much, but I am afraid going to be worse.

BTW - Thanks for everybody again.

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

I too would guess that the X-contrast is what is messing with you. LCD monitors have very saturated contrast in general, so pushing it higher rarely helps.

Also, if you get dancing or wierd looking pixels or ghosting, try the Auto Adjust feature on the monitor.

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

From my limited experience using X contrast it will do just that. The white is extremely white. But a dark scene is very dark. I never really use it for just that reason.

The pixels jumping around would normally be those 2 caps on the main/logic board. I think you said you had replaced those. The fuzziness, or pixelation, is usually all over everywhere. I'd check the lvds ribbon/cable to the main/logic board and clean it. I have never witnessed random pixelation like that. Maybe somebody else knows. Check those 2 caps, and the lvds cable.

[Castor8]

Re: Hanns-G HG281D, LCD Monitor no power

Happy New Year!

I'd like to add something to my previous post.
I changed all the caps that Lumberjack777 marked me (#704 - red and blue equally). I forgot to say what I did to fix it.

I watched a movie yesterday,I turned on the "X Contrast", the display was glaring. It was unbelievable - very-very beautiful images.
But in the darker scene went to darker (like automatically decrease the brightness). Than on the scenes under the light or daylight went back to normal (extremely bright).
Is this a real function with the "X Contrast" or an other malfunction next to the pixels friability (pixels jumping around)?

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

Congratulations. Thanks for the feedback. Happy New Year!

[Americanpiegamer188]

Re: Hanns-G HG281D, LCD Monitor no power

Parts came today and I got it fixed!! Replaced the 2 capacitors and I am shocked it worked.

I had/have no soldering skills. Radioshack has a $10 off $25 coupon so I bought a soldering iron, solder, and wicking for super cheap. Got the caps from digikey.

I am so happy!

[Castor8]

Re: Hanns-G HG281D, LCD Monitor no power

Finally I fixed it yesterday. Now it is working properly.

Thank you very much indeed for all. I am very happy now.

But now it makes relatively high noise like a transformer or something. Is it ok?

And I have an other issue. There are some flickering, running around in the middle(quadrant) of the display. I mean flashing pixels (I don't know how to say it in english) Sometimes are black, sometimes are white, it depends on the background color.
Can I fix it somehow?

[Americanpiegamer188]

Re: Hanns-G HG281D, LCD Monitor no power

Thank you very much! Hope shipping times are alright.

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

I saw your link for the exact model in another post. Do you have the links for the other capacitors on this board as well? They seem to cheap to order that it couldn't hurt? Shipping is the real cost when only buying 2.

I was scrolling under the same type and it only goes down to 17uF and it calls for a 10uF 25V

You don't need to buy more and replace any others. Those have always lasted on other similar monitors before. It's also a waste of time soldering caps that don't need replacing.
I realize (2) @ 53 cents apiece, plus 3 or 4 dollars shipping doesn't seem cost effective. But it is. Basically you'll repair for monitor for about 5 bucks. (or less)

Here's a link to the ones you want (2) http://www.digikey.com/product-detai...0CT-ND/3072210

[Americanpiegamer188]

Re: Hanns-G HG281D, LCD Monitor no power

Excellent pictures. That helps a lot.
Ok, this sounds like the 2 caps on the main/logic board, next to the voltage regulator, in your first picture.
Replace the 2 in this picture I have attached. This repair, and the picture, are courtesy budm.

This is through hole soldering and it doesn't hurt to practice on an old motherboard or similar. Here's a youtube video that explains through hole soldering. https://www.youtube.com/watch?v=Z38WsZFmq8E

You can order the 2 caps from digikey. Panasonics are good. Make sure to get 105c rated.

I saw your link for the exact model in another post. Do you have the links for the other capacitors on this board as well? They seem to cheap to order that it couldn't hurt? Shipping is the real cost when only buying 2.

I was scrolling under the same type and it only goes down to 17uF and it calls for a 10uF 25V

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

Excellent pictures. That helps a lot.
Ok, this sounds like the 2 caps on the main/logic board, next to the voltage regulator, in your first picture.
Replace the 2 in this picture I have attached. This repair, and the picture, are courtesy budm.

This is through hole soldering and it doesn't hurt to practice on an old motherboard or similar. Here's a youtube video that explains through hole soldering. https://www.youtube.com/watch?v=Z38WsZFmq8E

You can order the 2 caps from digikey. Panasonics are good. Make sure to get 105c rated.

[Americanpiegamer188]

Re: Hanns-G HG281D, LCD Monitor no power

I read through all of this thread and I don't know where to start. I have a Digital Mutlimeter and not an ESR meter.

When connected through HDMI the monitor normally stays on for 2 seconds and then goes to black. When connected through VGA sometimes it works and sometimes it doesn't. When it does, it is extremely hazy.

Here are my pictures. Please advise where to start or what to replace! I have a soldering iron and am willing to try it!

I don't see any capacitors out of the ordinary - bulges or leaks.. but I've never replaced one before.

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

If it were me. I'd just buy those 3 caps (circled in red) from my picture. Just get high quality caps like the others mentioned. With 105c rating, because the monitor runs hot. You could also buy the full kit from the place budm mentioned. We are just trying to make sure you get high quality caps for the job. Just make sure the repair person knows how to solder well. Good luck!

[Castor8]

Re: Hanns-G HG281D, LCD Monitor no power

I wrote an e-mail to him since a week to the "support e-mail address", but nobody has answered me yet.

Do you think I should order this item anyway?

http://lcdalternatives.com/Hanns-G-H...-P2087771.aspx (This is the same link as above)

thanks

[budm]

Re: Hanns-G HG281D, LCD Monitor no power

I bought these from Conrad. Are they ok?



The guy in the store said that the 35V caps will be ok, cause does not matter 16V or 35V. Is it true? I have never tried to repair anything like my monitor, so I hope I am not going to ruin it.

No, it is general purpose cap and only 85c, this monitor runs hot.

[budm]

Re: Hanns-G HG281D, LCD Monitor no power

Forget about my last question please.

Should I have to order this, instead of buying those 3 caps?

http://lcdalternatives.com/Hanns-G-H...-P2087771.aspx

He is my friend and he uses good caps, I help him out a lot on the cap selection and technical questions. Just tell him Bud sends you.
just make sure you get the one that MATCHES your power supply VERSION.