Hanns-G HG281D, LCD Monitor no power

[Mishannya]

Re: Hanns-G HG281D, LCD Monitor no power

OK. I've just found 3 dry caps (C603,606 and 707). Going to buy repair kit and replace all of them. Thanks to every body for your support.

[jetadm123]

Re: Hanns-G HG281D, LCD Monitor no power

OK. I've just found 3 dry caps (C603,606 and 707). Going to buy repair kit and replace all of them. Thanks to every body for your support.

Make sure your kit includes ALL the caps. I've seen some kits that leave out the small caps.

[Mishannya]

Re: Hanns-G HG281D, LCD Monitor no power

Thanks for your advice.

[retiredcaps]

Re: Hanns-G HG281D, LCD Monitor no power

OK. I've just found 3 dry caps (C603,606 and 707). Going to buy repair kit and replace all of them.

Let us know if new caps solve the problem or not.

[Mishannya]

Re: Hanns-G HG281D, LCD Monitor no power

I will. Thanks for your help.

[Mishannya]

Re: Hanns-G HG281D, LCD Monitor no power

Just repaired my Hanns-G HG281D, LCD Monitor. Replacing 3 dry caps (C603,606 and 707 & couple more small one) returned monitor back to normal life. Thanks to every one for help and support. Best regards.

[retiredcaps]

Re: Hanns-G HG281D, LCD Monitor no power

Just repaired my Hanns-G HG281D, LCD Monitor. Replacing 3 dry caps (C603,606 and 707 & couple more small one) returned monitor back to normal life.

Good work. Saving a 28 inch monitor from the landfill is a good feeling.

[rushstrike]

Re: Hanns-G HG281D, LCD Monitor no power

I have a problem with this monitor where it takes about 50 tries to get it to turn on. Once it is on everything works perfectly. Is there a good way to test the power supply board? I would like to plug in the AC power and turn on the board without using the monitor's power button. I see that in the back there's a printout that says PSON so I wonder if I can use that some how to turn the board on. Let me know of any suggestion. Thanks.

[PCBONEZ]

Re: Hanns-G HG281D, LCD Monitor no power

Did you check the switch?

[PlainBill]

Re: Hanns-G HG281D, LCD Monitor no power

I have a problem with this monitor where it takes about 50 tries to get it to turn on. Once it is on everything works perfectly. Is there a good way to test the power supply board? I would like to plug in the AC power and turn on the board without using the monitor's power button. I see that in the back there's a printout that says PSON so I wonder if I can use that some how to turn the board on. Let me know of any suggestion. Thanks.

Perhaps a little more detail would help. Do you have to hit the power button on the monitor repeatedly to get it to turn on, or does the problem occur when you apply AC power?

The power supply in this monitor is a dual design - the standby section of the monitor is always on and takes only a few watts (possibly less than 1 watt). The main section is switched on only when it is active and draws most of the power.

The symptoms you describe sound like bad capacitors, and the layout of the power supply looks like it was designed to kill caps!!

PlainBill

[jetadm123]

Re: Hanns-G HG281D, LCD Monitor no power

I have a problem with this monitor where it takes about 50 tries to get it to turn on. Once it is on everything works perfectly. Is there a good way to test the power supply board? I would like to plug in the AC power and turn on the board without using the monitor's power button. I see that in the back there's a printout that says PSON so I wonder if I can use that some how to turn the board on. Let me know of any suggestion. Thanks.

Please post some photos (top and bottom) of the power board per PlainBill's links in Post #30.

[rushstrike]

Re: Hanns-G HG281D, LCD Monitor no power

Yes the switch has been physically checked. It seems to open and close just fine using an ohm meter. According to this post, it seems that the problem is most likely due to the power supply board. If I unplug the AC cord and replug it into the wall, it seems like it has a better chance of turning on than me just repeatedly hitting the power switch. I will take some photos once I am home from work.

Did you check the switch?

[rushstrike]

Re: Hanns-G HG281D, LCD Monitor no power

Perhaps a little more detail would help. Do you have to hit the power button on the monitor repeatedly to get it to turn on, or does the problem occur when you apply AC power?

The power supply in this monitor is a dual design - the standby section of the monitor is always on and takes only a few watts (possibly less than 1 watt). The main section is switched on only when it is active and draws most of the power.

The symptoms you describe sound like bad capacitors, and the layout of the power supply looks like it was designed to kill caps!!

PlainBill

The monitor can sometime turn itself on right when I plug in the AC power. Then sometimes it can turn on when I try to press the power button repeatedly. Once I can turn it on, I can turn it off and on for about 5 times consecutively before it stops responding.

[jetadm123]

Re: Hanns-G HG281D, LCD Monitor no power

My initial guess is the startup capacitor is acting up. It's under that metal cover. Can you remove it and retake the photo?

[retiredcaps]

Re: Hanns-G HG281D, LCD Monitor no power

The monitor can sometime turn itself on right when I plug in the AC power. Then sometimes it can turn on when I try to press the power button repeatedly. Once I can turn it on, I can turn it off and on for about 5 times consecutively before it stops responding.

Like the OP, all his caps looked good (no bloating), but after testing with an ESR meter, he found 3 dry caps and proceeded to switch them all out and save a 28 inch monitor.

If you have a multimeter, see if you get stable 5V STB DC (details in previous posts).

[PlainBill]

Re: Hanns-G HG281D, LCD Monitor no power

As is common for larger monitors, there is a PFC front end on this power supply. MORE complication. I would agree with retiredcaps. Do replace all electrolytics, especially the tiny ones.

PlainBill

[rushstrike]

Re: Hanns-G HG281D, LCD Monitor no power

My initial guess is the startup capacitor is acting up. It's under that metal cover. Can you remove it and retake the photo?

I think I will try to check the caps first with the ESR meter since I have to desolder this cap in order to remove that metal cover. I dont have a soldering iron with me atm.

[Fatweed]

Re: Hanns-G HG281D, LCD Monitor no power

Hi there,
Just to add my 2 cents, I had a dead Hanns-G HG281D too, and after following the advice and info here I managed to get this dead monitor working again.
There were 3 dry caps that were measuring low/incorrect capacitance once removed from the power supply, which were C603,606 and 707 also found by Mishannya. (these caps did not look puffy or leak either on inspection)

Many thanks to this great site!

[algomez]

Re: Hanns-G HG281D, LCD Monitor no power

I'm in the process of recapping the power board on my HG281D as well. Ordered the caps from Digi-key, on their way now.

Mine turns on for a while (15 mins or so) then shuts off. I can turn it on again and same thing happens except it shuts off within ~10-20 secs.

My power board looks different than yours and has a manufactured date of May 2009. Here is a pic with cap values:

[jetadm123]

Re: Hanns-G HG281D, LCD Monitor no power

I'm in the process of recapping the power board on my HG281D as well. Ordered the caps from Digi-key, on their way now.

Mine turns on for a while (15 mins or so) then shuts off. I can turn it on again and same thing happens except it shuts off within ~10-20 secs.

My power board looks different than yours and has a manufactured date of May 2009. Here is a pic with cap values:

Your monitor is under 2 years old. Isn't it still under warranty? It would be suprising if the cap(s) failed that quickly.