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    #1

    HANNSPREE HF289H Black Screen No Power

    Hello everyone, I am having problems with my monitor and I'd like to see what you guys think the problem might be. As the title says I have a Hannspree 28" HF289H monitor that stopped working. My computer went into power saving mode the other day along with the monitor. When I moved the mouse the PC turned on but the monitor did not. No LED light anywhere. As a matter of fact I get absolutely no response from the monitor at all except when i plug in a video source I get an orange light that blinks once whether there is power or not. When I plug in the power source nothing at all happens. Every time I plug in a video source though whether its HDMI, or VGA I get that one orange blink before the light turns off. Now there is no picture on the monitor at all, no faded image nothing at all. It feels like the thing is not getting any power. I opened it up and looked around a bit and noticed that the inverter board, and power supply have significant discoloration. The video card I would assume is fine since I get a response from it when I plug a video source in. My question is, which part of the board do you guys think would cause this? Is it the inverter board, the power board, the video board, the backlight? Any help would be greatly appreciated, Thanks!

    Attached are some pictures that I took
    Attached Files
    Last edited by vfnpunk; 04-03-2012, 01:59 PM.
    Tags: None
    #2
    Re: HANNSPREE HF289H Black Screen No Power

    Start with this megathread. There are enough ideas, suggestions, and test points to get you started.

    https://www.badcaps.net/forum/showthread.php?t=11329
    --- begin sig file ---

    If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

    We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

    Please do not post inline and offsite as they slow down the loading of pages.

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    Comment

      #3
      Re: HANNSPREE HF289H Black Screen No Power

      Pics are not well focused. Please, upload new pictures if you can.

      Since I'm not a technician, this is what I'd do:

      - Check the power cord (if you get 110v at the end of it).
      - Look for not working caps (apparently none) and blown fuse(s).
      - If you get 110v on the board. If you do, then the voltage in the main cap filter and the bridge rectifier.

      I'm trying to find the service manual of the monitor but I can't find it.

      Comment

        #4
        Re: HANNSPREE HF289H Black Screen No Power

        Yeah sorry about the bad quality my phone camera is all I have available at the moment, and I did see that thread and some others before I posted, I posted on one of them a few days ago but didn't get a response so I decided to start my own thread. The thing with those is that I never really got a conclusive answer as to what part of the monitor caused the problem, or did I miss something?

        Comment

          #5
          Re: HANNSPREE HF289H Black Screen No Power

          It's actually a fairly complicated power supply and not easy to troubleshoot. Sounds like you're getting some power as evidenced by the orange led coming on for a second. On the lower left of your third picture there is a row of pins for each of the wiring harnesses. There should be markings on the board to indicate the 5V, 5VSB, 12V and 24V outputs. Once you record this info on paper, connect everything back together except for the inverter and with your meter set to DC volts, try measuring for the above voltages at each connector. Especially interested in the 5VSB as this should be on at all times.
          Last edited by jetadm123; 04-03-2012, 09:42 PM.

          Comment

            #6
            Re: HANNSPREE HF289H Black Screen No Power

            The orange light flashes on even when the monitor is not connected to the power at all. It comes from the video source

            Comment

              #7
              Re: HANNSPREE HF289H Black Screen No Power

              Have you checked what I said?

              Comment

                #8
                Re: HANNSPREE HF289H Black Screen No Power

                Since it appears that the original poster is awal, I'll bring this thread back to life. I have the same problem with the same monitor. I've gone over the power supply with a multi meter and its getting the correct amount of input voltage but none of the output pins are reading what is expected. For verification, do I need to hook all of the boards back up to the power supply to truthfully validate the voltage level? Thanks for any help that you can give.

                Comment

                  #9
                  Re: HANNSPREE HF289H Black Screen No Power

                  Yes you need all boards connected. Do not expect members to read back to another case - Your problem may not be exactly the same.
                  If you need more help restate the problem. How it started and where it is at now. Say what happens from when you plug in until it reaches a stable state. Report any sounds /Flashes from back light/ anything on screen and the state of the power led. It is also best if you have a live source connected. Say what testing you have done and list the results.

                  Welcome to the forum-
                  We can help a lot more if you please post good clear pictures of the whole chassis, and then pictures of each board, front and back and close up of connectors, (max resolution 2000x2000 and 2MB) using the manage attachments button, which is found by clicking "go advanced" under quick reply.

                  Please do not post inline and offsite as they slow down the loading of pages.

                  Examples of what is needed
                  https://www.badcaps.net/forum/attach...1&d=1290283049

                  https://www.badcaps.net/forum/attach...7&d=1280167246

                  It will be useful if you can say a bit about yourself - skills tools etc.
                  Please upload pictures using attachment function when ask for help on the repair
                  http://www.badcaps.net/forum/showthread.php?t=39740

                  Comment

                    #10
                    Re: HANNSPREE HF289H Black Screen No Power

                    Thank you for the quick and thorough response. As soon as I get back into town, I will take pictures of everything. I won't be able to answer anything about when the monitor died because I picked it up from someone that was tossing it out.

                    Comment

                      #11
                      Re: HANNSPREE HF289H Black Screen No Power

                      Too hard to tell from your photos, but this monitor may have the same power board as the infamous Hanns G 28 inch megathread. If yes, there are hundreds of posts in that one thread and several forked off threads for you to do some homework.

                      https://www.badcaps.net/forum/showthread.php?t=11329
                      --- begin sig file ---

                      If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                      We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                      Please do not post inline and offsite as they slow down the loading of pages.

                      --- end sig file ---

                      Comment

                        #12
                        Re: HANNSPREE HF289H Black Screen No Power

                        So I tried to upload some photos but I keep getting an error message and once received a message about a missing token from the website. Not sure what the issue is but I'll update you on what I did find. I hooked everything back up and plugged it in. It's getting 120v, the power button and all other connections on that board are not getting any voltage reading. The 5VSB pin is only getting 2.5v instead of 5v. There is a yellow box(side of it reads 250v) near the 120v plug that is near the input female plug (that initially connects to the wall). One pin of that yellow box is reading 119v while the other pin is reading 0v. Other than that, I haven't found any other cable connections that have voltage being passed to them. I'm learning as I go here so thank you for your time and willing to work with me. If this goes well, I have a radio for my 1966 pickup that has some dried capacitors that needs replaced next. I can only hope that it's easier to fix.

                        Comment

                          #13
                          Re: HANNSPREE HF289H Black Screen No Power

                          Originally posted by welch_41 View Post
                          So I tried to upload some photos but I keep getting an error message and once received a message about a missing token from the website. Not sure what the issue is but I'll update you on what I did find.
                          You'll get that error message if the images are too large.
                          The limit is 2000x2000 pixels and 2MB. If either the filesize or the image dimensions are larger than those values, you'll get the misleading security token error.

                          Comment

                            #14
                            Re: HANNSPREE HF289H Black Screen No Power

                            Thanks for the hint...

                            corrected...Thanks again.
                            Attached Files
                            Last edited by welch_41; 06-12-2012, 09:59 PM.

                            Comment

                              #15
                              Re: HANNSPREE HF289H Black Screen No Power

                              uhm.. you better remove those inline-posted images. Many of the gurus on here won't respond to threads with giant inline images. There have been a ton of discussions about this recently..

                              Comment

                                #16
                                Re: HANNSPREE HF289H Black Screen No Power

                                Would it be best if I just start a new thread?

                                Comment

                                  #17
                                  Re: HANNSPREE HF289H Black Screen No Power

                                  Originally posted by welch_41 View Post
                                  Would it be best if I just start a new thread?
                                  No, you are doing alright here- pictures are good and clear, thanks. Can you do the bottom of the power boards and the top and bottom of the main board
                                  And the inverter board - ie same set as the original poster. To get it clear you may have to do the inverter board in 2 parts.

                                  We can then locate where you need to do testing. Is the rest of the heat shield
                                  soldered on?. Can you locate where the BIG Cap is on the back of the board and which is the positive and negative leg. First test is with it all connected up and plugged in -CARE as HIGH Voltages- set meter on 600vDC and put the red probe on the positve leg and the black probe on the negative leg and report the voltage should be around 170vdc. Then press the
                                  power button and quickly but carefully do the same test - may be up to 400vdc.
                                  Please upload pictures using attachment function when ask for help on the repair
                                  http://www.badcaps.net/forum/showthread.php?t=39740

                                  Comment

                                    #18
                                    Re: HANNSPREE HF289H Black Screen No Power

                                    I'm working on the photos for the rest of the boards. Before I started to strip it apart, I checked the big capacitor underneath the metal plate and it was reading 280vDC. Unfortunately, I can't get too close to it without desoldering the metal plate. I did try the power button but nothing happened. No blue light, no increase in voltage on the big cap, no picture...

                                    Comment

                                      #19
                                      Re: HANNSPREE HF289H Black Screen No Power

                                      I hope that this gets me a little closer to a solution.
                                      Attached Files

                                      Comment

                                        #20
                                        Re: HANNSPREE HF289H Black Screen No Power

                                        I forgot to mention that this monitor was in a home that experienced a lot of voltage spikes.

                                        Comment

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