Syncmaster 245bw going dim/bright at times after all caps/resistors replaced.

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  • OberAgain
    Member
    • Nov 2014
    • 25
    • USA

    #1

    Syncmaster 245bw going dim/bright at times after all caps/resistors replaced.

    I just did a replacement of all caps/resistors for the 245bw, I have done it a few times prior to fix my other monitors and this was definitely the second+ repair done on this board (first by me, bought off ebay)
    Anyways, now when windows dialog boxes come up it gets dim, or with I use this Windows Tweaker program it gets really bright then slowly dims back down and to a yellowish tint after every change made. The monitor works fairly decent as long as you ignore the random changes in brightness when you open/close anything.

    The previous repair was done really sloppy and made it extremely tough to get the parts out without doing damage, on the 3x 68ohm resistors I had a few spots where I thought I lost the trace pad but I was able to solder to it - just not as clean as I would hope and do not expect it to be easily fixed again unless I replace with a single 200ohm resistor, even then I have to work with the worst damaged pad/hole.

    Also both me and a friend notice this purple outline of stuff that is not on screen just barely visible on completely black backgrounds - sometimes it acts up and gets more visible, turned down brightness to reduce effect.

    One random stupid question, I have failed to replace that plastic "shield" on all the monitors that I have repaired (just forgot about it when putting back together) but its just a piece of thin semi-transparent plastic do I am not sure if it really shields anything but a friend tried to tell me he thought that the purple looked like possible interference? I thought it was simply a cover to make sure no one touches the more dangerous section of the PCB?

    Is it likely that this is a power board issue or one of the other parts?

    I have searched for other people reporting similar things with the model but couldn't find any.

    Thank you all as usual, your all great! Best helpful site on the web!
  • CapLeaker
    Leaking Member
    • Dec 2014
    • 8118
    • Canada

    #2
    Re: Syncmaster 245bw going dim/bright at times after all caps/resistors replaced.

    can you upload some high resolution, straight shot pictures of your boards?

    Comment

    • OberAgain
      Member
      • Nov 2014
      • 25
      • USA

      #3
      Re: Syncmaster 245bw going dim/bright at times after all caps/resistors replaced.

      Well, I was hoping it was something that would be somewhat identifiable by the symptoms, the next time I take it apart I will take the pictures. Thank you for your time and I apologize for not having the pictures ready to start with.

      Comment

      • CapLeaker
        Leaking Member
        • Dec 2014
        • 8118
        • Canada

        #4
        Re: Syncmaster 245bw going dim/bright at times after all caps/resistors replaced.

        are these three 68Ohm resistors in series or in parallel?

        Comment

        • OberAgain
          Member
          • Nov 2014
          • 25
          • USA

          #5
          Re: Syncmaster 245bw going dim/bright at times after all caps/resistors replaced.

          Series, they are a common problem in Syncmaster 245bw's

          Comment

          • CapLeaker
            Leaking Member
            • Dec 2014
            • 8118
            • Canada

            #6
            Re: Syncmaster 245bw going dim/bright at times after all caps/resistors replaced.

            what is the dim voltage doing?

            Comment

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