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    #1

    LCD Monitor problem!

    I figure this is a good place to post. Well here's a short story. bought this unit from best buy in a replacment ace monitor that lasted 2 days then smoked. hahaha. It's a westinghouse 19" wide screen. Realy nice moniter. Well it quit working. Tryed to take it back to best buy but they mest up the recieped and i gues technicly i stole this moniter cause all the reseip shows is the old monitor and they can't help me. Well i quit shoping there.

    Anyway this moniter powers up. And loses picture in 2 seconds. Vary's now and then. I leave it set for a month it'll stay on for at least 5 min. every time i change any settings like the res, pixles, or anything in the display settings in my comp...it'll pop back on for a few seconds and go back off. Light stays green. Then eventualy goes into standby. And before you ask yes i have read just about every post in here tonite about westinghouse problems. And i got gutsy and opend it. And honestly it still looks new. No discolor anywere on the board. And all the capaciters look great. No baldgy ones that is. And i can't afford another monitor. Got laid off two weeks ago. enough of the sob story..lol. I just figured i would try to fix it. The monitor i use now has always been my back up...but it's old...not sure how much longer it has so i would like to keep it as a back up...lol Any sugestions? I will snap some pictures tommorow if i need to.

    thanks.
    Mitch
    Tags: None
    #2
    Re: LCD Monitor problem!

    wow this is embarasing replying to my own post...and bad spelling...anyway...lol. Wow i've learned alot this morning about capacitors. I gues they dont always bulge when they are bad. So how can i test to see if they are bad. Well i'm getting ahead of myself. I'm working on the pictures right now. I forgot to add in my symtoms...that sometimes it cycles power off/on a few times then goes into standby. that just started. I may have screwed somthing els up trying to get it to stay on. (sigh) i hope not.

    Comment

      #3
      Re: LCD Monitor problem!

      ok here are the pictures. My question is on one of these photos i took had little flat blue capacitors on it. How do you know they are bad. I'm sorry i'm new at this but i love this kind of stuff.
      Attached Files

      Comment

        #4
        Re: LCD Monitor problem!

        You need an ESR meter to test the capacitors. Let us know the brand of capacitors so we can maybe identify if they are a "known bad" series.

        Comment

          #5
          Re: LCD Monitor problem!

          Originally posted by Mitch
          ok here are the pictures. My question is on one of these photos i took had little flat blue capacitors on it. How do you know they are bad. I'm sorry i'm new at this but i love this kind of stuff.
          The symptom you describe is typically called 'two seconds to black'. It indicates a problem with either the CCFLs or the inverter. Briefly, here is how the backlight system works.

          The monitor is turned on, the backlight controller drives the CCFLs at full power for several seconds, then checks for a number of possible fault conditions These may include voltage across the CCFL is too low or too high, current through the CCFL is too low or too high. If a fault condition exists, the controller shuts down the CCFLs.

          Possible problems include a bad CCFL, a broken CCFL, open or shorted transformer, or a problem with the current or voltage monitoring circuitry. In general, the first step towards troubleshooting the problem is to substitute known good CCFLs. The CCFLs used with case mod kits are often used for this.

          Yes, it is POSSIBLE the little blue caps are bad, but this is unlikely.

          PlainBill
          For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

          Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

          Comment

            #6
            Re: LCD Monitor problem!

            xtraelectronics- ESR meter ok. the type of capacitors are CapXon and there are also 2 Taicon caps also. thank you for the meter info.


            PlainBill- Thank you for the great information i was wondering how the power line up worked. Now the (CCFL) what is that? And i'm sorry i'm still learning the abreviated lingo.

            Comment

              #7
              Re: LCD Monitor problem!

              Originally posted by Mitch
              xtraelectronics- ESR meter ok. the type of capacitors are CapXon and there are also 2 Taicon caps also. thank you for the meter info.


              PlainBill- Thank you for the great information i was wondering how the power line up worked. Now the (CCFL) what is that? And i'm sorry i'm still learning the abreviated lingo.
              CCFL = Cold Cathode Florescent Light AKA backlight. They are 4mm diameter glass tubes which provide the light. A typical monitor will have 4 or 6 of these.

              Ultra short lesson: The inverter takes (typically) 12 VDC and steps it up to 600 - 1000 VAC at 100 Khz. This voltage powers the backlights.

              PlainBill
              For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

              Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

              Comment

                #8
                Re: LCD Monitor problem!

                >>...And i'm sorry i'm still learning the abreviated lingo.<<

                See:

                https://www.badcaps.net/forum/showthread.php?t=7295

                Of which CCFL is not a part of....?
                veritas odium parit

                Comment

                  #9
                  Re: LCD Monitor problem!

                  Anyone know where i might be able to get schematics for the lcm-19w4?

                  Comment

                    #10
                    Re: LCD Monitor problem!

                    Hi all me again. I just want to say i'm realy confused. I set this job aside cause i had no meters. My soldering iron kit seemed to be MIA. Well i got it all and sat down and was going to write down all the number on the caps. I was going to try testing and replacing those first. and then go from there. But.....might big but. i for some reason thought "All what the hell lets hook it up while apart on the tabel" well it started doing the same old. It cycled power a few times. i picked it up to listen were the clicks were coming from..not loud but the click you hear when you hit the power button. When it got done cycleing..it stayed on. and now i can't get it to do it again. I parshaly put it back together to test run it. Played a game on it. Serf the net for an hour. Then.....yes i did it.....lol. Left it on allllll night. I get up this mornning...it's still working great. My friend wants to buy it for his studio...but i have a bad feeling it's going to do it again. But i'm just confused..anyone got any ideas? And thank you for all the information so far and this is a wonderfull forum. Great and helpfull people here.

                    Comment

                      #11
                      Re: LCD Monitor problem!

                      Still working............................lol

                      Comment

                        #12
                        Re: LCD Monitor problem!

                        Originally posted by Mitch
                        Hi all me again. I just want to say i'm realy confused. I set this job aside cause i had no meters. My soldering iron kit seemed to be MIA. Well i got it all and sat down and was going to write down all the number on the caps. I was going to try testing and replacing those first. and then go from there. But.....might big but. i for some reason thought "All what the hell lets hook it up while apart on the tabel" well it started doing the same old. It cycled power a few times. i picked it up to listen were the clicks were coming from..not loud but the click you hear when you hit the power button. When it got done cycleing..it stayed on. and now i can't get it to do it again. I parshaly put it back together to test run it. Played a game on it. Serf the net for an hour. Then.....yes i did it.....lol. Left it on allllll night. I get up this mornning...it's still working great. My friend wants to buy it for his studio...but i have a bad feeling it's going to do it again. But i'm just confused..anyone got any ideas? And thank you for all the information so far and this is a wonderfull forum. Great and helpfull people here.
                        How good is this friend? As one of my co-workers would say "Problems that go away by themselves come back by themselves." I wouldn't sell it to anyone who will be depending on it unless you replace the caps in the inverter section and resolder all the pins on the transformers.

                        PlainBill
                        For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

                        Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

                        Comment

                          #13
                          Re: LCD Monitor problem!

                          I agree totaly. And being the fact i'm a green horn (noob) at this stuff. I didn't tell him I fixed it...lol. I'm going to let it set for a bit and give it time to act up again. Thanks again for all the great info on this site. Love it.

                          Comment

                            #14
                            Re: LCD Monitor problem!

                            Hello to all, this is my first post in the forums, but have been lurking for quite some time.
                            I have exactly the same monitor, and the same symptoms appeared about a year or two ago, it would go to standby all by itself while I was using it with no reason or change of signals from the computer. Then it got worse, it would not turn on sometimes, then it won't start up at all, I just get a green and orange led light.
                            I opened and checked for the usual things, cold solder, broken paths, fuses, resistors, all looked and measured fine....(I don't have a ESR meter so caps were not checked, but I'm sure they all shall be replaced, (two Capxon 1000/25, two 220/25, one 22/50, one Taicon 2200/10 and one 1000/10).

                            Power supply voltages are fine though, 12v and 5v are ok and fuses do not blow, actually what I think is that the main problem is not the power supply but the scaler chip on the data board, it used to overheat when the problem started, I installed a heat sink and worked for quite some time but then it died. (maybe due to dirty power from the caps)
                            Now if I touch some of the pins or surrounding components with bare fingers, I sometimes get power to the CCFL and a full screen white background with some random red vertical lines. (I know it's not recommended, but it was a desperate attempt to get some response from the circuit, and it worked!)
                            Since the chip is hard to find/replace (and I guess it's factory programmed for the corresponding timings and column/row matrix of the LVDS drivers, I guess my only solution is to replace the board. I already ordered it from DM and will keep you informed of the results. (I will also order the caps, unfortunately couldn't find them here so I'll have to look elsewhere for them.)
                            Any comments or suggestions will be very appreciated.

                            Comment

                              #15
                              Re: LCD Monitor problem!

                              Originally posted by bravotronics View Post
                              I have exactly the same monitor
                              Which monitor? I don't see any model/make mentioned anywhere in this thread?

                              Now if I touch some of the pins or surrounding components with bare fingers, I sometimes get power to the CCFL and a full screen white background with some random red vertical lines. (I know it's not recommended, but it was a desperate attempt to get some response from the circuit, and it worked!)
                              Your "bare fingers" bring this quote by Mark Twain into my mind.

                              "A man who carries a cat by the tail learns something he can learn in no other way.
                              --- begin sig file ---

                              If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                              We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

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                              Comment

                                #16
                                Re: LCD Monitor problem!

                                Originally posted by retiredcaps View Post
                                Which monitor? I don't see any model/make mentioned anywhere in this thread?
                                Post #9.

                                PlainBill
                                For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

                                Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

                                Comment

                                  #17
                                  Re: LCD Monitor problem!

                                  Originally posted by PlainBill View Post
                                  Post #9.

                                  PlainBill
                                  Oops!

                                  Time for another beverage. Off to the fridge ...
                                  --- begin sig file ---

                                  If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                                  We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                                  Please do not post inline and offsite as they slow down the loading of pages.

                                  --- end sig file ---

                                  Comment

                                    #18
                                    Re: LCD Monitor problem!

                                    Originally posted by retiredcaps View Post
                                    Oops!

                                    Time for another beverage. Off to the fridge ...
                                    Good call, I'll follow your advice
                                    "The one who says it cannot be done should never interrupt the one who is doing it."

                                    Comment

                                      #19
                                      Re: LCD Monitor problem!

                                      Originally posted by retiredcaps View Post
                                      Which monitor? I don't see any model/make mentioned anywhere in this thread?
                                      I didn't see the model either, until Mitch's request for schematics, but I identified it through the pictures....


                                      Originally posted by retiredcaps View Post
                                      Your "bare fingers" bring this quote by Mark Twain into my mind.

                                      "A man who carries a cat by the tail learns something he can learn in no other way.
                                      Oh well, if you are refering to finger-testing CRT flyback transformers, CCFL, etc.... been there, done that..... I know quite well the little but deep (and painful) scars from HV burns, (I usued to do it for pleasure... ) call me a freak.....
                                      BTW, my new caps and card are on the way, I'll keep you informed about the repair results.

                                      Comment

                                        #20
                                        Re: LCD Monitor problem!

                                        Parts arrived and installed....... Monitor working like new again...hoorah.!!!
                                        It was an easy repair considering this monitor was discarded as "unrepairable" by one of the best service centers in my country where I took it before attempting to buy the parts myself......
                                        Next project: replace caps on my other 2 LCD monitors before they fail: twin AOC 22" and my brother's Viewsonic 22"

                                        Thanks for the help guys.

                                        Comment

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