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Hanns-G HG281D, LCD Monitor no power

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    Re: Hanns-G HG281D, LCD Monitor no power

    No problems .

    Let us know if you ever get problems with the monitor again.
    Although, if you used genuine Panasonic caps on the logic and power supply boards, this monitor should make it at least 5 more years of trouble-free operation.

    Comment


      Re: Hanns-G HG281D, LCD Monitor no power

      Originally posted by _BtB_ View Post
      hey thanks for the help
      the pics posted of the power board are not the same as mine, I managed to snap a few pics but they are not of the best quality. Its the best I could do without buying a camera.

      So I will just recap the entire 2 boards and see how that goes. here is the cap list

      logic board:
      3 x 470uf 16v
      12x 10uf 25v
      5x 100uf 16v

      power board:
      2x 1000uf 35v
      2x 680uf 25v
      4x 10uf 50v
      1x 33uf 35v
      2x 1000uf 16v
      1x 100uf 16v
      1x 220uf 10v
      1x 220uf 25v

      and here is the digikey cart sharing (i think this will work)
      http://www.digikey.com/short/7rb0vr

      Is everything in the digikey cart accurate?

      thanks
      Originally posted by Lumberjack777 View Post
      Lucky you. That's the easier one to repair. Try replacing the 3 caps circled in red. Feel free to change any circled in blue if you want. But the 3 circled in red are usually the problem.

      Make sure to pull straight out on the cap when desoldering. I have seen some botched repairs where the person pushed back in a little on the cap, and lifted the thin copper trace and pad. Those pads lift easily if you push on the cap.

      Hi Lumberjack777,

      I've got the same boards as BtB and same list of Caps to buy. Since I've got the ones that are "harder to repair." Should I just replace them all or are there a few suspect caps on these other versions?

      BtB, did you manage to fix your Hanns by replacing all the caps listed?

      Thanks!

      Comment


        Re: Hanns-G HG281D, LCD Monitor no power

        Hi Hapollo. You know, I have never had one of the alternate power boards like you and BtB have to repair. It's always been the one I will attach here. But since your board was manufactured around the same time that many manufacturers were using the inferior caps; there's a good chance you have some bad ones. You could replace them all (If you are fairly skilled and have the time). I have an ESR meter so I can test them. In my experience on the other board, it was the smaller caps that tended to dry up. Especially in the middle. It's really up to you. If I didn't have an ESR meter, I'd start with the smaller caps that aren't bulging. Or just replace them all. Hope that helps.
        P.S. I did hear of a guy that fixed your board by replacing some caps. But I don't know which ones he replaced. So there is hope
        And you want to replace the 2 caps budm mentions on the logic/main board (photo attached)
        Attached Files

        Comment


          Re: Hanns-G HG281D, LCD Monitor no power

          Originally posted by Lumberjack777 View Post
          Hi Hapollo. You know, I have never had one of the alternate power boards like you and BtB have to repair. It's always been the one I will attach here. But since your board was manufactured around the same time that many manufacturers were using the inferior caps; there's a good chance you have some bad ones. You could replace them all (If you are fairly skilled and have the time). I have an ESR meter so I can test them. In my experience on the other board, it was the smaller caps that tended to dry up. Especially in the middle. It's really up to you. If I didn't have an ESR meter, I'd start with the smaller caps that aren't bulging. Or just replace them all. Hope that helps.
          P.S. I did hear of a guy that fixed your board by replacing some caps. But I don't know which ones he replaced. So there is hope
          And you want to replace the 2 caps budm mentions on the logic/main board (photo attached)
          Thanks Lumberjack777, I don't have a ESR meter but have replaced many many caps on defective LCD TVs from the 2008 era, mostly Samsungs and typically those have been the larger 1000uf or 2200uf. Rarely have I had to replace anything less than 100uf.

          These Hanns seem to be the reverse, mostly small <100uf fail and the larger ones seem ok. Having read your earlier post that it's always the same smaller ones and a waste of time and money to replace the larger ones:

          https://www.badcaps.net/forum/showth...451#post504451

          As with any small qty cap purchase orders, the shipping is typically greater than the cost of the dozen caps. Guess I will order the whole lot that BtB listed, start with the smaller ones and then progress to the larger ones if after just replacing the smaller ones don't work.

          Maybe it's time to invest in an ESR meter

          Thanks for the quick reply and HAPPY 4th!

          Comment


            Re: Hanns-G HG281D, LCD Monitor no power

            SO, I have the Hanns G power supply thats the easier of the 2 to fix. I ordered a kit prior to understanding that. The kit doesnt have a few of the caps outlined in red for some reason. Ive already taken out C605, C606, C603, C707, and C403. I read on another forum a guy replacing some of the larger caps with different values. Am I suppose to replace these with the same values or are there alternate replacements?

            Please advise. Thanks.

            Comment


              Re: Hanns-G HG281D, LCD Monitor no power

              The microfarad value needs to be the same. The voltage can be a little higher. A 100uF 16v cap can be replaced by a 100uF 25v cap. You'll need to replace the 3 I had circled in red for sure. Those 3 always go out. I'd replace all the small ones in the middle of the board just to be safe.

              You need to be careful on that board because the manufacturer bent the cap leads all the way over. So when people melt the solder, and pull on the cap, it can take the copper trace, and/or the pad with it. I like to melt the solder and stick a tiny screwdriver in there, and bend the wire lead up a little at first. Then pull it out.

              Comment


                Re: Hanns-G HG281D, LCD Monitor no power

                Do you have a list of those values? Somebody moved all my caps from my work bench... I had them setting in position to where they came out. Should have wrote them down...

                Yeah I noticed the leads bent down. Tried pulling them straight with the iron and almost flicked solder in my eye. I know I had some safety glasses around here somewhere...

                Comment


                  Re: Hanns-G HG281D, LCD Monitor no power

                  I don't have those values. Sorry. I think if you go through the entire thread you'll find a pic somewhere. Or google images.

                  I make it a habit of replacing 1 or 2 at a time because I don't want to write it all down. And I can't remember more than 1 or 2 at a time. Works for me.

                  Comment


                    Re: Hanns-G HG281D, LCD Monitor no power

                    OK found it. Post #727 from Castor8 7th image. Will try to re-post the image here in case anybody needs it.
                    Attached Files

                    Comment


                      Re: Hanns-G HG281D, LCD Monitor no power

                      Hi,

                      at first, thank you all for your excellent advice ! I succeeded to bring back to life a HG281D by changing just 2 caps on the video card.
                      But before this result, i tried to change a lot of caps on power and video card of another HG281D: strange area of red pixels disappeared and i can turn it on instantly. The problem is that i cannot change brightness anymore!
                      On OSD i can move from 0 to 100, but nothing changes on the screen, it is like the brightness is blocked at 0 ... Someone already saw that ? Any idea on what to do to solve this problem ? I checked continuity with a multimeter and everything seems ok, maybe a cap that i replaced is bad, but which one ?
                      Thanx in advance for your help,

                      Greetings from France

                      Comment


                        Re: Hanns-G HG281D, LCD Monitor no power

                        Have one of these HG28 monitors that went out. Started with the power supply and replaced all caps with panasonic's. Did not fix the problem.

                        Next I replaced the three big caps on the logic/control board, followed by the five 100uf caps which brought the monitor back to life but not 100%. Problem now is that the colors seem off and the center of the display has a yellowish tint (left and right side and bottom seem to have less yellowing).

                        I have a couple questions would greatly appreciate feedback from you experts.

                        o) Is it possible that a bad cap (or poorly soldered cap) on the PS or logic board would cause the yellow tint issue(still have 9 small caps on the logic board to go). Or is it more likely a problem with the backlight or other issue?

                        o) If a bad cap could be the problem any tips to narrow things down.

                        I could try replacing the remaining 9 small caps on the logic board to rule this out but what if one of the replaced ones is bad, cold solder joint, open ...

                        o) Can the caps be easily destroyed by overheating? Know they are not as sensitive as transistors, but a few got a little hotter than I would have liked.

                        Any pointers appreciated.

                        Comment


                          Re: Hanns-G HG281D, LCD Monitor no power

                          Per previous post, attached photo of the problem with the yellowed screen after recap.

                          The second photo shows some artifact from the camera (does not look this way) but the pattern seen by camera might shed some light on the problem.

                          Any ideas as to what to check next appreciated.

                          Thanks,
                          Kuma
                          Attached Files

                          Comment


                            Re: Hanns-G HG281D, LCD Monitor no power

                            Hi,

                            I have some problem with my HG281D. It started to go black than works fine for a sec and than goes black again, and it circling till warm up.
                            Anybody has any idea?

                            Regards,
                            Castor

                            Comment


                              Re: Hanns-G HG281D, LCD Monitor no power

                              Try changing those two caps on the logic board first:
                              https://www.badcaps.net/forum/showpo...&postcount=783

                              But the power supply should also be re-capped.
                              Never stop learning
                              Basic LCD TV and Monitor troubleshooting guides.
                              http://www.badcaps.net/forum/showthr...956#post305956

                              Voltage Regulator (LDO) testing:
                              http://www.badcaps.net/forum/showthr...999#post300999

                              Inverter testing using old CFL:
                              http://www.badcaps.net/forum/showthr...er+testing+cfl

                              Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                              http://s807.photobucket.com/user/budm/library/

                              TV Factory reset codes listing:
                              http://www.badcaps.net/forum/showthread.php?t=24809

                              Comment


                                Re: Hanns-G HG281D, LCD Monitor no power

                                Thank you.
                                I will do it, than I will let you know the result.

                                Comment


                                  Re: Hanns-G HG281D, LCD Monitor no power

                                  Please check my post #727.
                                  I changed everything a bit more than a year ago.
                                  Do you think I should repeat the whole process again?

                                  Or at least I should change those 2 even If they are not older than 1,5 years?

                                  Comment


                                    Re: Hanns-G HG281D, LCD Monitor no power

                                    Originally posted by Castor8 View Post
                                    Please check my post #727.
                                    I changed everything a bit more than a year ago.
                                    Do you think I should repeat the whole process again?
                                    That would be this one, I suppose:
                                    https://www.badcaps.net/forum/showpo...&postcount=727

                                    My answer to your question above is YES and NO.

                                    Yes, repeat the process of changing ALL of the capacitors that you changed last time.

                                    No, do NOT use Yageo / Teapo capacitors again. Yageo / Teapo (especially the SC series, which you showed us in this picture) are an extremely poor choice for monitor use (and for anything, actually - Teapo is often said to be as bad as CapXon around here... and CapXon is well known to fail regularly).

                                    Use only quality *Japanese* capacitors (i.e. Panasonic, Nichicon, Rubycon, and United Chemicon), and make sure to pick a low-ESR series as well. Avoid eBay and local stores for buying capacitors - most Japanese caps there are counterfeit. I see that you are in Europe (Hungary), so I guess you can buy your caps from either RS Components, Farnel, Badcaps.net, or contact member Behemot here (he's based in CZ, IIRC).

                                    Speaking of low-ESR caps, here is an updated list of series that you can use:
                                    https://www.badcaps.net/forum/showpo...22&postcount=9
                                    Last edited by momaka; 02-20-2016, 08:33 PM.

                                    Comment


                                      Re: Hanns-G HG281D, LCD Monitor no power

                                      I fixed it. It works fine, better than ever.

                                      Thank you very much again.

                                      Comment


                                        Re: Hanns-G HG281D, LCD Monitor no power

                                        Originally posted by Castor8 View Post
                                        I fixed it. It works fine, better than ever.

                                        Thank you very much again.
                                        So you changed all the caps again with better quality one?
                                        Never stop learning
                                        Basic LCD TV and Monitor troubleshooting guides.
                                        http://www.badcaps.net/forum/showthr...956#post305956

                                        Voltage Regulator (LDO) testing:
                                        http://www.badcaps.net/forum/showthr...999#post300999

                                        Inverter testing using old CFL:
                                        http://www.badcaps.net/forum/showthr...er+testing+cfl

                                        Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                                        http://s807.photobucket.com/user/budm/library/

                                        TV Factory reset codes listing:
                                        http://www.badcaps.net/forum/showthread.php?t=24809

                                        Comment


                                          Re: Hanns-G HG281D, LCD Monitor no power

                                          I only changed those 3 poor quality caps, which was changed by monitor repair man. I did not change those Panasonics I did a year ago.

                                          And my other problem also solved. Those white filckering pixels around or I have no idea what they were... Atteched pics.

                                          So everything is perfect by now.
                                          Attached Files

                                          Comment

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