Hanns-G 281D -- No power, Replaced Powerboard

[tylerwerrin]

Re: Hanns-G 281D -- No power, Replaced Powerboard

When I tried plugging everything in and turning the unit on, I get nothing -- no blue light, no orange light nada. The SB voltage continues to fluctuate from 4.8V down to 3.8V. When I probed the 12V & 24V rails, I got no change in the fluctuation.

[tom66]

Re: Hanns-G 281D -- No power, Replaced Powerboard

Try replacing the startup cap.

[tylerwerrin]

Re: Hanns-G 281D -- No power, Replaced Powerboard

could you direct me to the startup cap on my pictures? would it be a big one, or a smaller one?

[tylerwerrin]

Re: Hanns-G 281D -- No power, Replaced Powerboard

is it c603, c606 or c707? I had read on the previous mega-post about this same monitor that these three are traditionally the problem children of this board.

[retiredcaps]

Re: Hanns-G 281D -- No power, Replaced Powerboard

1) U201 might be your 8 pin SMPS controller for 5V SB.

2) On the top should be a part number. Use the part number to find its datasheet.

3) On the datasheet, there will be one pin called VCC.

4) Now power off and unplug your lcd.

5) Put your multimeter on continuity.

6) Put your red probe on the VCC pin.

7) Put your black probe on the positive leg on C205, then C203.

8) The one that beeps is your startup cap.

[tylerwerrin]

Re: Hanns-G 281D -- No power, Replaced Powerboard

hi retiredcaps,

well, i got ahold of the company in china -- they are gonna send another board out. however, i'm not holding my breath that this one will work any better than the one they sent previously.

In the meantime, i have been searching for the datasheet for my board so I can locate the VCC to track down the starter cap. I haven't had any luck -- an old post about this same board had a data sheet linked here:

http://html.alldatasheet.com/html-pd...SDM0265RL.html

I'm not really that familiar with the sheets, so I'm not sure what I should be looking for. The exact post is this:

https://www.badcaps.net/forum/printt...&pp=20&page=11

It lists U601, but you had suggested 201, and it didn't look like there was a consensus if that was even the correct sheet to begin with. Is there a good place to track down that info? I'm not even sure which is the "8 pin" connector because the only connectors on this board are 10 and 11 pins.

[retiredcaps]

Re: Hanns-G 281D -- No power, Replaced Powerboard

What is the part number on U201?

[tylerwerrin]

Re: Hanns-G 281D -- No power, Replaced Powerboard

Hi guys,

Well I got my new board, and for the last couple days it worked fine but it started getting harder and harder to turn on and now it's not turning on again.

I measured the SB voltage, and it would fluctuate from 4.97V down to 3.9v and then back up to 4.97. I'm guessing this board has the same problem as the other replacement board, as well as the original board. I'm going to try replacing the caps again, this time on board #2 and see what happens.

[retiredcaps]

Re: Hanns-G 281D -- No power, Replaced Powerboard

Well I got my new board, and for the last couple days it worked fine but it started getting harder and harder to turn on and now it's not turning on again.

I measured the SB voltage, and it would fluctuate from 4.97V down to 3.9v and then back up to 4.97.

The above symptoms suggest caps with high ESR just like Mishannya.

https://www.badcaps.net/forum/showthread.php?t=11329

As I have mentioned several times with this particular monitor, it runs temperature hot and seems to dry out most of the caps on the power and main board.

Your seller obviously has no testing procedures to verify that these boards are good.

[tylerwerrin]

Re: Hanns-G 281D -- No power, Replaced Powerboard

yep, makes sense. At least the replacement board came free of charge. I posted on the homepage asking for a "re-cap" service, due to my crappy soldering/desoldering on the original board, which I destroyed but didn't get a response.

The solder points are alot smaller than i'm used to dealing with, dangit!

[Lumberjack777]

Re: Hanns-G 281D -- No power, Replaced Powerboard

Seems like this board is going out on a lot of people at the same time. In the attached picture. The caps circled in red definitely need to be replaced. And you should also replace the ones circled in blue because they might eventually dry out too. Good luck! L-J-7

[Qbass70]

Re: Hanns-G 281D -- No power, Replaced Powerboard

does someone have a complete list of the caps for this board?

[selldoor]

Re: Hanns-G 281D -- No power, Replaced Powerboard

does someone have a complete list of the caps for this board?

Yes - you do, assuming you have the board in front of you.

[SamJohns]

Re: Hanns-G 281D -- No power, Replaced Powerboard

I just saw this page and just finished repairing this board in discussion.
I know it is late but someone might be just repairing the board so here is the answer to the last question.

Attached is a file with the caps used on this board ( PSM217-404-H-R ).



~Sam~

[tylerwerrin]

Re: Hanns-G 281D -- No power, Replaced Powerboard

thanks! thats helpful to see it listed like that. i actually have all the caps, just never got around to diving in... too afraid!

[st0n3r]

Re: Hanns-G 281D -- No power, Replaced Powerboard

Ive been sitting with a dead monitor for about a year now. Loved it when it worked, but nothing anymore. Just seems like 0 power is going through it. Guess Ill spend the $10 on caps and try it out. Looking at the board / caps they all look in good shape. Where did you all order the caps from? Cant find part numbers?