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    Acer 1916N goes blank after 2-3 seconds

    Hi there.
    I'm not native English speaking person, so if something is not clear please let me know and I will try to explain it more detailed.

    Power supply is 220V 50Hz.

    I have Acer 1916N monitor, which when turned on it lights, shows the ACER logo, but the fade in effect is shown like frames which the normal eye could catch. And right after the logo is shown, the monitor goes blank (total darkness), nothing is visible on the background under external light (so I think it's not background light issue). However, the power LED is always ON and do not switch OFF, neither blinking, or switch to orange (when sleep).

    I read the other posts for similar monitors in this class AL1916, but nothing of the listed things help me.

    I don't see any bad caps, or other burn in elements. However, the main power board has brown areas due to hearing or something like that, and the logic board has one regulator which seems to be heating, but when I measure it shows good voltages.
    Also, the big PET capacitor is in good looking shape (don't be mistaken by the labels .. they are printed in non-perfect line .. the capacitor has perfect cylindric form) and under power shows 310V, but on the positive lead it has small drop of something like dry electrolyte which I push and if falls.

    Under power, the voltage on the cable between power and logic board shows the same values as listed on the power board (next to the connector)..
    So between black and red wires I have 4.95V/4.96V as listed on the board (5V).

    The attached images are both used in this monitor.

    Any ideas what could be wrong and did somebody has been working on similar issue?
    Thanks!
    Attached Files

    #2
    Re: Acer 1916N goes blank after 2-3 seconds

    Your BIG cap is faulty - leaking electrolyte and should be replaced.
    Do not continue to use it as they have been known to explode.

    Wait for a second opinion if you want

    Your mains voltage should be 230v so Big cap should be 322vdc
    Last edited by selldoor; 11-28-2012, 01:01 PM.
    Please upload pictures using attachment function when ask for help on the repair
    http://www.badcaps.net/forum/showthread.php?t=39740

    Comment


      #3
      Re: Acer 1916N goes blank after 2-3 seconds

      Change that big cap, do not try to run the monitor otherwise a lot of AC ripple will cause damage to the other components.
      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


        #4
        Re: Acer 1916N goes blank after 2-3 seconds

        Hmm,
        Ok guys, tomorrow morning I will change that with new one and then will check if will works.

        Meanwhile I'm opened for any other ideas

        Comment


          #5
          Re: Acer 1916N goes blank after 2-3 seconds

          We will have lots of ideas if that does not fix it but until you have
          safe steady voltages you have nothing.

          In case it still doesnt start you should read this if you have not already.
          Almost all the tests in it do not need power on.

          https://www.badcaps.net/forum/showthread.php?t=10419 start at post 19

          and if you have any spare ccfls other screens dead laptops look them out.
          may be required for testing
          Please upload pictures using attachment function when ask for help on the repair
          http://www.badcaps.net/forum/showthread.php?t=39740

          Comment


            #6
            Re: Acer 1916N goes blank after 2-3 seconds

            OK, the BIG capacitor is replaced, but the problem stay the same.

            Same frames during the logo fade-in ... and when the monitor was off for longer time, actually I get a windows desktop after the Acer logo.
            However, just before it went blank again, it pop-up a message box saying "Signal not Supported".

            Any more ideas?

            Comment


              #7
              Re: Acer 1916N goes blank after 2-3 seconds

              "Signal not Supported".
              That can mean the video resolution output from PC is too high for the monitor to display.
              Last edited by budm; 11-29-2012, 05:52 PM.
              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


                #8
                Re: Acer 1916N goes blank after 2-3 seconds

                Yea, but I check that and it was in normal ...

                1024x768 at 60Hz
                This should be supported by the monitor for sure

                Sorry that I forget to mention that.

                Comment


                  #9
                  Re: Acer 1916N goes blank after 2-3 seconds

                  I think I have a monitor that says that while windows is booting then when its up and running it corrects itself. That is however the least of your problems - you can sort that when you have a monitor that stays on
                  Have you read the two seconds to black.

                  Now you have replaced the big cap, with it all connected can you re test the voltages at the connector between the power supply and the main board. Please post them like:
                  pin1 12v 11.98
                  pin2 pson 2.99.
                  pin3 5v 5.1 and so on

                  Then With the power OFF

                  On the attached picture I have marked two fuses - please check them - meter on ohms 200 should read 0.0 post result.

                  Also I have marked the secondary wiring on the inverter transformers. With the power off and your meter set on ohms 2000 chack s1>s2 and S3 >S4 and post the result
                  Attached Files
                  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: Acer 1916N goes blank after 2-3 seconds

                    Hi selldoor,

                    I think I have a monitor that says that while windows is booting then when its up and running it corrects itself. That is however the least of your problems - you can sort that when you have a monitor that stays on
                    Have you read the two seconds to black.
                    Well, the PC was running before I test the monitor, so wasn't booting at the moment, but was fully loaded. I check the resolution and the frequency on an old CRT brand CTX monitor and it was 1024x768 @ 60Hz. Then I just switch the cables between both monitors. And when the monitor shows the windows screen for a second, just before to show the "Input not Supported" was showing the same resolution as on the CTX monitor.

                    Yes, I read the two seconds to black topic. The instructions are very very good. However, for sure mine is not an CCFL lamp issue, because under external light there is no picture at all, just total darkness.
                    I'm doing checks on the elements by this instructions right now to see if there is any transistor or something else not working.

                    Here are the data you request:
                    When everything is connected and power is ON, the connector voltages are this:

                    pin1 O/F 2,443V
                    pin2 DIM 3,195V
                    pin3 12V empty
                    pin4 GND empty
                    pin5 5V 4,86V
                    pin6 5V 4,86V
                    pin7 GND
                    pin8 GND

                    The second measurements with power OFF show this data ....
                    Fuses measurement shows:
                    F902 - 0.0
                    F903 - 0.0

                    The secondary wirings on the inverter transformers shows this values:
                    S1 > S2 - 450 Ohm
                    S3 > S4 - 453 Ohm

                    I will post if I found anything suspicious on the elements check depending on the two seconds to black topic instructions.

                    I'm open for any other fresh ideas
                    Thanks!

                    Comment


                      #11
                      Re: Acer 1916N goes blank after 2-3 seconds

                      When you say pin 3 is "empty", do you mean it reads 0V? It's a 12V output which drives the inverter section.

                      Comment


                        #12
                        Re: Acer 1916N goes blank after 2-3 seconds

                        No, I mean that there is no cable going out of the connector
                        In the pictures of the first post you can see that not all pins of the connector has cables attached

                        Comment


                          #13
                          Re: Acer 1916N goes blank after 2-3 seconds

                          Anyone .. anything? I really have no ideas and the elements I measure don't seems to have any problems

                          Comment


                            #14
                            Re: Acer 1916N goes blank after 2-3 seconds

                            I think we are struggling with the idea that there is no 12 volts.
                            Does the connector cable have a wire.
                            Can you mark on the backs of both boards which is the 12v pin


                            EDIT
                            Doesnt matter - I can see there is no wire-
                            Could this cable be off another board?
                            Could the wire have been removed?
                            Last edited by selldoor; 12-03-2012, 10:54 AM.
                            Please upload pictures using attachment function when ask for help on the repair
                            http://www.badcaps.net/forum/showthread.php?t=39740

                            Comment


                              #15
                              Re: Acer 1916N goes blank after 2-3 seconds

                              Looking at your power supply photos a little more closely, there are two diodes to the left of the wiring harness. One diode is mounted on the aluminum heatsink and the other (marked D922) is by itself. Measure the DC voltage of the middle pin of the diode mounted on the heatsink. It's probably 5V. If you measure the DC voltage of the side marked with a white line on D922, you should see something around 12V. Once you have verifed the proper voltages, then you can proceed to check other things.

                              Comment


                                #16
                                Re: Acer 1916N goes blank after 2-3 seconds

                                Hi guys

                                Originally posted by selldoor View Post
                                Could this cable be off another board?
                                Could the wire have been removed?
                                No, when I open the monitor it was like this, nothing is removed.


                                Originally posted by jetadm123 View Post
                                Looking at your power supply photos a little more closely, there are two diodes to the left of the wiring harness. One diode is mounted on the aluminum heatsink and the other (marked D922) is by itself. Measure the DC voltage of the middle pin of the diode mounted on the heatsink. It's probably 5V. If you measure the DC voltage of the side marked with a white line on D922, you should see something around 12V. Once you have verifed the proper voltages, then you can proceed to check other things.
                                Ok, the diode mounted on heatsink is D920. The middle pin of that diode shows 14.65V.
                                The other one (D922), shows on the cathode (white line) 4,9V.

                                Both voltages are measured against the GND1 ground. This is the one on top of the connector (the nearest one).

                                Hope that helps. I'm still waiting for any other ideas, because I can't think of anything else.

                                Comment


                                  #17
                                  Re: Acer 1916N goes blank after 2-3 seconds

                                  Well I guess the main board must not need 12v so it is just on the power supply board and will drive the inverter section. Some monitors when you change the caps have to have a factory reset ( I read somewhere and dont know why , maybe has an eeprom) does it stay on long enough to get into the OSD and do a reset.
                                  Also if you have just been plugging it into a running pc how about setting the pc on 640*480 resolution ( lowest) then closing it down. Have the monitor switched off then plug in the vga cable to the pc. Switch on the pc press f8 to open in safe mode and tell us what happens. Does your pc allow for 2 screens to be connected? if so you could check what it thinks this screen is.
                                  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: Acer 1916N goes blank after 2-3 seconds

                                    Good suggestion ...
                                    In the moment I have an WinXP running under recovery mode to check the HDD for bad sectors. The other monitor is like in DOS mode, so I just plug the problem monitor to the PC and stay ON for much longer (I don't count the seconds, because I try to go faster to the OSD), but for sure it was 30 seconds showing the DOS mode.
                                    I found the reset option into the OSD and run it, after that, the monitor went blank again. I turn it off (from the power too) and then turn it on, but now after the ACER logo it goes blank after 2-3 seconds again even when it's in DOS mode.

                                    However, I see something. Like I write above, the ACER logo is loading in frames. But when it shows the DOS mode with all the texts, all texts are not stable. I mean that they do some kind of blinking, but not disappear at all .. it's some kind of going silver (less white) and then 100% white again.
                                    After it go blank, I check again with external light, but there was nothing in the background, so it doesn't seems to be lamps.

                                    Seems like in lower resolution (and just black with text .. no colors) was much stable than in 1024x768, but now I cannot recreate that stability after the reset.

                                    Comment


                                      #19
                                      Re: Acer 1916N goes blank after 2-3 seconds

                                      any ideas guys?

                                      Comment

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