low voltagw on 150uf 450v cap?

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  • capted
    Member
    • Feb 2011
    • 30

    #41
    Re: low voltagw on 150uf 450v cap?

    Check this out, I did not want to turn it off or unplug it until you wrote back.. I hit the power buttton on and off atleast 20 times with the 2 bulb connectors still connected and it powered on and offf no problem( no backlight still) so, I unplugged it and plugged it back in and nothing ,no power light.. I pulled the connectors off for the bulbs, unplugged it and hit the power button a bunch of times and now it started to light up again..

    Comment

    • budm
      Badcaps Legend
      • Feb 2010
      • 40746
      • USA

      #42
      Re: low voltagw on 150uf 450v cap?

      When the monitor was working, if it is not connected to the running PC, does the power light turn off or turn Amber?
      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

      • capted
        Member
        • Feb 2011
        • 30

        #43
        Re: low voltagw on 150uf 450v cap?

        I do not know, it was handed to me to try to fix. I do alot of pc work and laptop repairs. I have fixed about 48 lcd's and a few tv's. I just like the knowledge when I have problem like this one for next time. I just can't stop!!!!
        The power is still on without the bulbs connected. The last time I pugged the connectors in for the bulbs they came on. Do you think I should do one at a time and restart or all at once. I don't get why the 2 connectors that were plugged in did not light the 2 bulbs(now that you told me each connector is one bulb) I think I will plug it into a pc now when the power light is on and see if it goes amber sleep mode.

        Comment

        • capted
          Member
          • Feb 2011
          • 30

          #44
          Re: low voltagw on 150uf 450v cap?

          Just plugged it to one of my laptops and the power led went amber....

          Comment

          • budm
            Badcaps Legend
            • Feb 2010
            • 40746
            • USA

            #45
            Re: low voltagw on 150uf 450v cap?

            You can do one bulb at a time to see if it even light up for second, just do it in the dark room, it will go into shutdown but at least you can tell if the bulb is not completely broken. The lamp assembly can have bad wire which will still light up the bulb for second, all you can do right now is to find out if one of the bulb is complete bad or not.
            If you plan to work on more monitors, then you should get one this inverter to test the lamps, it will safe you so much time.
            http://www.ebay.com/sch/i.html?_trks...at=0&_from=R40
            By the way, can you give me the P/N as printed on the inverter transformer? We need to find the pinout so we can check the winding resistance.
            Last edited by budm; 10-25-2012, 09:02 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

            • capted
              Member
              • Feb 2011
              • 30

              #46
              Re: low voltagw on 150uf 450v cap?

              I have no idea what the deal is.. After you asked me if it went to sleep when a pc was connected it all changed. the light went amber and I plugged the usb port in and my laptop had the extra usb ports from the monitor.. So I did one bulb at at time restarted the monitor and it lit up a for a second and went dim. The big deal is I got the menu all the time even after it went dim(like dead bulbs but the logic board still works) Itried each one, one at a time--same thing. Than I was thinking what you said that it will shut down the bulbs if there was a problem..... plugged in all the bulbs and it works ..It is still on now..I jus dont get it. I am do not want to unplug it and do this all over again. But I know if I do it won't start again.. This time I took pics of it working so you would not think i'm nuts. Is it possible that this thing locks itself out from starting when it has a problem? What if the vga cord was shorted before I Got it??

              Comment

              • budm
                Badcaps Legend
                • Feb 2010
                • 40746
                • USA

                #47
                Re: low voltagw on 150uf 450v cap?

                I should have asked you if you have in connected to the running PC. If it does not detect video signals from the PC, it will go to sleep, amber light. I am beginning to think that the problem was the cold joints at the AC INLET since it does not have much support on it.
                http://s807.photobucket.com/albums/y...t=DSCF1116.jpg
                Last edited by budm; 10-25-2012, 10:04 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

                • capted
                  Member
                  • Feb 2011
                  • 30

                  #48
                  Re: low voltagw on 150uf 450v cap?

                  The [problem is I had no power light or sleep mode. I did the caps and re-soldered the entire board like the old ben-q's. still no good until you ask'ed about the connection to the pc.. It is still not together. The boards are loose in the case and the lcd is not secure. It's on the floor. I left it unplugged and will try it in the am. If it works I will put all of it back in the case and see if it works....

                  Comment

                  • capted
                    Member
                    • Feb 2011
                    • 30

                    #49
                    Re: low voltagw on 150uf 450v cap?

                    I purchased the 4 bulb inverter for testing bulbs..Great idea.

                    Comment

                    • capted
                      Member
                      • Feb 2011
                      • 30

                      #50
                      Re: low voltagw on 150uf 450v cap?

                      Update!!!! Today I unplugged it (it was working)...Plugged it back in and no good!! I replaced the 120v connector and put some small wires to the hot side and neutral side just to mak sure the copper traces did not break from the connector to the board... Bang it is on now and still on... Just want to keep all updated...

                      Comment

                      • budm
                        Badcaps Legend
                        • Feb 2010
                        • 40746
                        • USA

                        #51
                        Re: low voltagw on 150uf 450v cap?

                        It sounds like you need to scrape off some green coating on the copper to expose more copper to solder the connector to.
                        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

                        • capted
                          Member
                          • Feb 2011
                          • 30

                          #52
                          Re: low voltagw on 150uf 450v cap?

                          Originally posted by budm
                          It sounds like you need to scrape off some green coating on the copper to expose more copper to solder the connector to.
                          I did, and put 2 wires to connect the circuit.. I don't want to jump the gun, but so far O.K. Now the problem is, was it the caps and solder joints??? Or was it the power input? I might have screwed up the power socket on the bench when I plugged it in with no support for the board..



                          And Thank you for the help.. I will keep you posted as I let "burn in" still not sure if it is fixed.

                          Comment

                          • capted
                            Member
                            • Feb 2011
                            • 30

                            #53
                            Re: low voltagw on 150uf 450v cap?

                            So far still good. Let the p.c. sleep and the mintor wakes up and is working as it should. I wonder if it was a ground,neutral or line circuit that was erratic.. I'm thinking more ground or neutral because I tripped the gfi outlet when I was moving the 120v socket and checking my voltage.

                            Comment

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