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Steer me the right way on this Samsung 245BW of epic cruddyness?

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    Steer me the right way on this Samsung 245BW of epic cruddyness?

    Geez, I've spent days reading here now, and I've come to the conclusion that Samsung must have let the new guy design the 245B[W] or something. I guess, there are a few advantages to having the one that always breaks...looks like a few folks around here just about have the schematics memorized, heh.

    Anyhow, I'd appreciate if someone with more cluepons than I could look over my findings, and see if any of them are even slightly factual. I've played electricity some and only made my hair stand on end a couple times, but this is substantially beyond my previous experience. This dang thing cost way too much to just toss out tho, and besides...what am I gonna do, break it?

    My 245BW has always done the blue horizontal flickery lines thing after waking up from power saving. I figured out a power cycle would fix it, assumed it was a driver/firmware bug or something and forgot about it. All was good until the other day when it learned the other popular trick. Now it has the far too common 'screen blank but power LED behaves normally' thing...acts like it's turning on+off, goes to sleep, wakes up, etc...but the display is limited to a resolution of 1x1 at 1 bit color (blue light off, or blue light on...). [Sorry, I think I went a bit nutty reading the 20something page long 245BW thread...]

    Here's what I have found/speculated/invented while wishing I had a clue:

    - I have the more popularly broken BN44-00173A power board.
    - I believe RB805 is dead, RB806/RB807 appear okay
    - Inverter board requires new caps, C39 is tossing it's cookies (it's a miracle it worked long enough for RB805 to blow up...or could these be related?)
    - Caps on power board all look ok, but should probably be changed anyway
    - 24V appears dead (makes sense, I believe, without RB805)
    - All fuses seem okay (1 on inverter, 3 on power board), To the untrained eye, FB802S looks more like a fireplace than a fuse...reading 0.0 - 0.1 ohms though.
    - Not sure about CM802/RM802 - is it possible to test RM802 in circuit, or must a leg be lifted? If it can be tested in circuit, I believe it's toast...

    Basically, I'm concerned by the abundance of heat marks on the power board, and by the great difficulty that a few people had in getting it going. I'd be interested in giving a go at changing some stuff, but not if the whole thing is generally toasty. Any advice is welcome...no fancy equipment got a seemingly acceptible DMM that does ohms and volts. Don't have a sufficiently powerful soldering iron yet, but willing to get one. Camera isn't the best, but hopefully it'll work. Love you guys forever if you help me quit using this teeny tiny 19" CRT that is taking up six times the deskspace

    Oh, and I'd stress more about picture quality, but this board seems so well documented that I hope it's not a problem If needed, I can take some closer up, and paste them together/zoom em out or something...manual anti-aliasing hehe.
    Attached Files

    #2
    Re: Steer me the right way on this Samsung 245BW of epic cruddyness?

    Just because you have had to read an epic thread there is no need to create another one - this would probably have been enough:
    - I have the more popularly broken BN44-00173A power board.
    - I believe RB805 is dead, RB806/RB807 appear okay
    - Inverter board requires new caps, C39 is tossing it's cookies (it's a miracle it worked long enough for RB805 to blow up...or could these be related?)
    - Caps on power board all look ok, but should probably be changed anyway
    - 24V appears dead (makes sense, I believe, without RB805)
    - All fuses seem okay (1 on inverter, 3 on power board), To the untrained eye, FB802S looks more like a fireplace than a fuse...reading 0.0 - 0.1 ohms though.
    - Not sure about CM802/RM802 - is it possible to test RM802 in circuit, or must a leg be lifted? If it can be tested in circuit, I believe it's toast...



    I'd be interested in giving a go at changing some stuff, but not if the whole thing is generally toasty

    We dont know at this point if it is a quick fix or even a no fix

    My suggestion would be to replace the 3 resistors and the known to be faulty caps then come back if it doesnt work.

    Fuse is ok. RM 802 test in circuit compare with color bands.
    If you have to lift it you may as well replace it - its not going to add much to your outlay.

    Photos are not really sharp enough and whilst the board may be well documented you have chosen to start a new thread.
    I dont have the inclination to keep skipping back to another thread to find the board numbers so that I can tell you which particular diode on your board looks quite heated and needs tested. I cant read the number on your picture so you will have to guess.
    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: Steer me the right way on this Samsung 245BW of epic cruddyness?

      I believe RB805/RB806/RB807 should all measure 68 ohms.

      I'm not sure what the purpose of these resistors is... Looks like maybe bias power for the standby controller IC but I can't tell.

      You will quickly learn that Samsung prices its products high on the retail sticker, but inside they are very poorly made. Often a little better than the really cheap ones, but not much better.
      Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
      For service manual, schematic, boardview (board view), datasheet, cad - use our search.

      Comment


        #4
        Re: Steer me the right way on this Samsung 245BW of epic cruddyness?

        All I know it that the three 68 Ohms are hooked up in series. Still trying to figure out their functions in the circuits.
        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


          #5
          Re: Steer me the right way on this Samsung 245BW of epic cruddyness?

          Thanks for the replies, probably be early next week before I get much of a chance to work on it again but I'll try to start rounding up some supplies. I'll let you all know when I destroy it with my poor soldering skills

          Comment


            #6
            Re: Steer me the right way on this Samsung 245BW of epic cruddyness?

            Hopefully, you have at least a digital multimeter to perform basic measurements. RB805 is a common failure on your board. As was said previously, it's a 68 ohm resistor. If it measures bad, then replace all 3 of the 68 ohm resistors. RM802 seldom fails, it should read 1 Meg ohm. CM802 is the second most common failure. It's rated at 18nf 630V. C39 on the inverter board is clearly bad and when you replace it make sure you also replace the other green cap next to it.

            Comment


              #7
              Re: Steer me the right way on this Samsung 245BW of epic cruddyness?

              I thought I'd resurrect this thread to report a belated success! After letting it gather dust for a few months, I replaced the three 68 ohm resistors and the monitor came to life! I did not replace the capacitor that appears to be puking its guts out on the inverter board, though I know I really should...but I'm really stoked by the success so far - this was the first project of this nature I've tried, so if anyone has a similar problem and is hesitating to dive in for the first time, you can do it!

              Thanks to everyone who has posted advice and guides on this board, you saved my monitor

              Isaac

              Comment


                #8
                Re: Steer me the right way on this Samsung 245BW of epic cruddyness?

                Great. You should also remove ALL the glues on the components.
                https://www.badcaps.net/forum/showth...763#post279763
                read post 569 and up.
                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


                  #9
                  Re: Steer me the right way on this Samsung 245BW of epic cruddyness?

                  Originally posted by izzy View Post
                  I did not replace the capacitor that appears to be puking its guts out on the inverter board, though I know I really should...but I'm really stoked by the success so far -
                  That cap has a job to do, and it ain't gettin' it done if it's bloated and puking.
                  If it's not doing it's job other components will be stressin'

                  It's harder to disassemble a monitor than it is to replace a cap.

                  Nike.
                  36 Monitors, 3 TVs, 4 Laptops, 1 motherboard, 1 Printer, 1 iMac, 2 hard drive docks and one IP Phone repaired so far....

                  Comment

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