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    BenQ FP557 issue

    I know I shouldn't be posting too many new threads on an emergency account, but this was what I was trying to post on my Stevo1210 account when it crapped out.

    My friend has a 15" FP557 BenQ LCD which he wants me to fix. It still works and all assuming you can get it to turn on.
    The problem is that when you want to turn it on you have to wait 10-15 minutes before you get an image on the screen. Within the 10-15 minutes, the power light flashes green to amber continuously. After about 10-15 mintues it finally stabilises itself and decides to go to green and then turn on like any other monitor. But funny thing is that if you turn it off and turn it back on again, it comes on straight away. If the LCD is turned off for say 30 minutes, the problem comes back. My friend also noted that it comes on really quick on hot days, but on colder days it does the amber-green light thing continually until it wants to turn on and it can be a real pain sometimes.
    I suspect it might be bad caps because he did state that it comes on quicker on hot days or straight after being turned off and then on again.
    The backlight and everything else is fine. The picture quality is perfect, it's just this silly issue of the starting up that really bothers him and needs to be fixed.

    Thanks.
    This is "stevo1210" reporting in with this "new" emergency account as my other account doesn't work properly.

    #2
    Re: BenQ FP557 issue

    Stevo1210 is now officially online again. I was talking to my friend today and he said this issue only came to life a few months ago, so I suspect it has to be bad caps. I think that if say a transistor or something was faulty we would have noticed from the beginning and it would be dead as well and wouldn't turn on at all I suppose.

    Thanks.
    Don't find love, let love find you. That's why its called falling in love, because you don't force yourself to fall, you just fall. - Anonymous

    Comment


      #3
      Re: BenQ FP557 issue

      ... anyone?
      Don't find love, let love find you. That's why its called falling in love, because you don't force yourself to fall, you just fall. - Anonymous

      Comment


        #4
        Re: BenQ FP557 issue

        I a hobbyist but if it was mine, I would be in it looking to see if there is visible problem, and inspect all solder joint carefuly with magnifying glass and resolder any suspect solder or joints, it sounds like poss problem, if it is not then you can post back on what you do find in there that looks like a problem
        bob

        Comment


          #5
          Re: BenQ FP557 issue

          I managed to go over to my friends house yesterday to inspect this LCD monitor. Since it has been really cold recently, he has tried to turn his LCD on in freezing temperatures with no success and that power LED keeps flashing and with every flash if you listen carefully through the LCD's air vents, you can hear very faint clicks with every flash of that power light.... and I mean very faint because only the best of ears could hear it. When a bit warmer of course, the LCD will boot and stay on (not every time it's warm though.... hit and miss really).

          Anyway I did a visual inspection of the caps and this is what I found.

          2x 220uf 25V (8x10mm)

          1x 1000V 35V (12.5x25mm- approx height)

          2x 1000uf 16v (10x15mm - approx height)

          3x 470uf 25V (10x10mm- approx height)

          All of them are either Elite or Lelon brand. The Elite brand 1000uf 16V cap is very slightly bulged so I know that one is bad.... the others don't look bulged or popped but seeing as they are either Lelon or Elite brand I'm not taking my chances.

          Other than that the others are very small caps like 100-220uf of low voltages which I don't think are affected at all.

          So would you guys think it is wise to replace all the "larger" caps? I don't want to waste my friends money or ruin my image with electronics so yeah.

          Thanks.
          Last edited by stevo1210; 07-26-2009, 07:07 AM. Reason: Spelling error.
          Don't find love, let love find you. That's why its called falling in love, because you don't force yourself to fall, you just fall. - Anonymous

          Comment


            #6
            Re: BenQ FP557 issue

            do the larger ones. just to be safe.
            sigpic

            (Insert witty quote here)

            Comment


              #7
              Re: BenQ FP557 issue

              I have a dumpster Hann 19" that had similar symptoms. There were no caps with visible damage, so I replaced all those in the power supply circuit. Now, it works like new. This was before I got my ESR meter. I later checked those caps and only one had bad ESR, so it only takes one bad to shut the whole thing down. Good luck.
              Why throw it away? I might need it in the next 40 years. Duh!

              Comment


                #8
                Re: BenQ FP557 issue

                I'm doing this fix up job tomorrow.... I have bought new caps, or rather my friend has for the quick fix solution.
                We bought a bunch of Suntan branded caps because they were the only ones that were available locally. So after about 15 caps and a bill of $14 something, we have a whole bunch of low ESR caps (Only big caps, not small ones under 330uf).

                I hope this works....

                Thanks.
                Don't find love, let love find you. That's why its called falling in love, because you don't force yourself to fall, you just fall. - Anonymous

                Comment


                  #9
                  Re: BenQ FP557 issue

                  I have some good news and some bad news. The good news is that after replacing the caps on the power circuit, the monitor is now able to turn on and work again. But the bad news is that the lcd only displays white now... no colour, image or anything, just white... I looked at my soldering and it appears I haven't done any thing wrong in that sector... but why does it only show white now? what would be the cause of this?

                  thanks.
                  Don't find love, let love find you. That's why its called falling in love, because you don't force yourself to fall, you just fall. - Anonymous

                  Comment


                    #10
                    Re: BenQ FP557 issue

                    Originally posted by stevo1210
                    I have some good news and some bad news. The good news is that after replacing the caps on the power circuit, the monitor is now able to turn on and work again. But the bad news is that the lcd only displays white now... no colour, image or anything, just white... I looked at my soldering and it appears I haven't done any thing wrong in that sector... but why does it only show white now? what would be the cause of this?

                    thanks.
                    You havent by any chance left the lead to the panel and mainboard disconected either end
                    If you havent check the tiny fuse on the panel itself under plate up top of screen

                    Comment


                      #11
                      Re: BenQ FP557 issue

                      I've checked it and I can confirm that all appropriate cables are plugged in. I'm going to look for this fuse thing under the screen's top plate.
                      Don't find love, let love find you. That's why its called falling in love, because you don't force yourself to fall, you just fall. - Anonymous

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