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    Westinghouse 22w3 DAC 19M009

    There are a few threads on the forum which talk about bad caps in the 19M009. Initial issue in July 2015 was a bad rectifier which was replaced along with the main 120uF 400V cap. Since C200 and CE103 were questionable bulging they were also replaced with Nicicon's from Digikey in July 2015.

    In July 2018 the monitor stated going black after about 3 to 5 MINUTES. There is also a momentary buzzing/chirping sound when the monitor first starts until an image is displayed and when it goes black. I've opened the unit again and pulled the DAC. There are no obvious bad caps. Notice the heat discoloration around U202 and U203, it was there before the repair also. When powering the unit the temp on U203 runs about 92 F while U202 is 105 F. I've read that these P605's are like the HOT of the inverter and can generate a lot of heat. Should they be running different temps? But they seem to check ok with resistance in circuit. I have a 19M008 schematic, not a 19M009 but I believe the layouts are similar and only the component labels are slightly different.

    I'm not sure where to start. Should I test voltages with digital VM?
    Looking for help on this reliable daily user from my spouse. She is using a Dell 19" 4:3 in the meantime and misses her wider 16:9 screen. Happy wife is happy life, and my wife is not happy right now... So any help is appreciated.
    Cheers, BrianA_MN
    Attached Files

    #2
    Re: Westinghouse 22w3 DAC 19M009

    put the thing back together and turn the back light's as low as they go and let it run. See if it takes longer for the back lights to go off.

    Comment


      #3
      Re: Westinghouse 22w3 DAC 19M009

      Originally posted by CapLeaker View Post
      put the thing back together and turn the back light's as low as they go and let it run. See if it takes longer for the back lights to go off.
      Do this to determine what? In other words, what does this test? I'd like to learn. BTW - Happy New Year, I'm surprised anyone is on the board tonight! Cheers.
      Last edited by bvamunds; 12-31-2018, 06:54 PM.

      Comment


        #4
        Re: Westinghouse 22w3 DAC 19M009

        this trick is used on LCD and LED sets. Less brightness requires less power. Less power used, less heat produced.
        On a LED set it means bad LEDs in the back light.
        On a LCD set it could be cold solders, bad CCFL transformer etc.

        You didn't provide too much information on what exactly goes out. So I figure, that the monitor stays on, but the back light goes out.

        I did see cold solder joints on the PSU. Basically resolder anything that is under heat, transformer, heat sinks, the 2 IC's...
        Measure the output of the CCFL transformer winding on both transformers and compare them. If they are more than 3% apart, well... then one is toast. The bad transformer will run hotter than a good one. Looks like the transformer on the outer edge is a bit dis-coloured. That may explain why U202 runs hotter than U203.
        Hope that helps you to get started.

        Comment


          #5
          Re: Westinghouse LCM-22w3 DAC 19M009

          Originally posted by CapLeaker View Post
          this trick is used on LCD and LED sets. Less brightness requires less power. Less power used, less heat produced.
          On a LED set it means bad LEDs in the back light.
          On a LCD set it could be cold solders, bad CCFL transformer etc.You didn't provide too much information on what exactly goes out. So I figure, that the monitor stays on, but the back light goes out.
          This is an LCD screen with 4 CCFL's. It is a great suggestion. Sorry I forgot to test with the flashlight. It is now tested and indeed it is only the backlights which are going out, not the whole power. I can see the image when shinning a LED flashlight into the screen and moving it around I can see the image is present.

          If I change the brightness to nearly off, then the backlights stay on longer. Now I'm not sure if that eliminates the CCFL's as being the culprit, or if it simply means that one or more is starting to fail and with highest brightness will fail totally soon?

          Does the buzzing indicate that a transformer may be going? I saw a listing from 2009 that also suspected the yellow glue of the transformers has becoming conductive and possibly needing to be removed?

          Originally posted by CapLeaker View Post
          I did see cold solder joints on the PSU. Basically resolder anything that is under heat, transformer, heat sinks, the 2 IC's...
          Can you suggest a specific area of cold solder joints? This is an older board and while they look tarnished, I don't really see cold joints. But then maybe resoldering can't hurt?

          Originally posted by CapLeaker View Post
          Measure the output of the CCFL transformer winding on both transformers and compare them. If they are more than 3% apart, well... then one is toast. The bad transformer will run hotter than a good one. Looks like the transformer on the outer edge is a bit dis-coloured. That may explain why U202 runs hotter than U203.
          Hope that helps you to get started.
          They ohm out the same. I don't think they are bad, but maybe the buzzing is coming from one of them? I'll have to look through my spare CCFL's or make the 11W test lamps suggested in two minutes to black tutorial and see if I can up the brightness and figure out which CCFL is bad.

          Thanks for the on-going suggestions. Cheers, Brian

          Comment


            #6
            Re: Westinghouse LCM-22w3 DAC 19M009

            Originally posted by bvamunds View Post
            This is an LCD screen with 4 CCFL's. It is a great suggestion. Sorry I forgot to test with the flashlight. It is now tested and indeed it is only the backlights which are going out, not the whole power. I can see the image when shinning a LED flashlight into the screen and moving it around I can see the image is present.

            If I change the brightness to nearly off, then the backlights stay on longer. Now I'm not sure if that eliminates the CCFL's as being the culprit, or if it simply means that one or more is starting to fail and with highest brightness will fail totally soon?
            I don't think it is more. I would say either one CCFL or one transformer or these blue caps etc.

            Originally posted by bvamunds View Post
            Does the buzzing indicate that a transformer may be going? I saw a listing from 2009 that also suspected the yellow glue of the transformers has becoming conductive and possibly needing to be removed?
            That brown glue remove always on sight. It just spells trouble. A bad transformer always runs hotter.

            Originally posted by bvamunds View Post
            Can you suggest a specific area of cold solder joints? This is an older board and while they look tarnished, I don't really see cold joints. But then maybe resoldering can't hurt?
            Right on. Resolder everything. The connectors, the blue caps, the transformers and the little ICs. Sometimes you do not "see" cold solder joints with the eye.

            Originally posted by bvamunds View Post
            They ohm out the same. I don't think they are bad, but maybe the buzzing is coming from one of them? I'll have to look through my spare CCFL's or make the 11W test lamps suggested in two minutes to black tutorial and see if I can up the brightness and figure out which CCFL is bad.

            Thanks for the on-going suggestions. Cheers, Brian
            Well, my guess is that the transformer that buzzes is getting driven by that little IC that runs hotter than the other one. I can see from the picture that the buzzing transformer must be the one on the outer edge, because it is a little discolored = running hotter. The 11W CFL trick is a good idea. Usually faulty CCFL's are black on the edges and when they are on, they give a pinkish tint, not really white.
            You are learning fast!

            Comment


              #7
              Re: Westinghouse 22w3 DAC 19M009

              So in this monitor it appears a CCFL set is failing after further testing. The failing unit is probably the top set because the screen is not as bright on top. I had a spare old twin lamp set, which I plugged in to replace the top set. I then turned up the brightness to 90/100 and the monitor stayed on in excess of two hours. The interesting thing is if I turn the brightness down to 30/100 and the contrast up to 90/100 the lamps will still stay on in excess of two hours also. My wife tends to have her monitors blank-out after one hour.

              I'm still trying to figure-out the chirping. There is still a chirp when powering up or the monitor goes to sleep even with the replacement set in place. If I touch the outer lamp transformer in the dark I do see a discharge between my finger tip and the winding, which I don't see with the lower transformer. Perhaps the transformer is reading correct resistance but failing only under higher voltage demands and the internal short finds my finger or maybe I should attempt out-of-circuit measurements?

              This Westinghouse LCM-22w2 (note corrected model) has a Chi Mei A220Z1-H01 LCD screen assembly. It uses a Chi Mei M220Z1-L03 lamp set from CCFLWarehouse dot com. The lamp set is made of 2 lamps with total length of 490mm including silicon end caps.

              This monitor is the similar to both ACER2216W or ViewSonic VX2235W. I have used the available online service manuals to help, along with CapLeaker's help of course.
              Last edited by bvamunds; 01-07-2019, 01:00 PM.

              Comment


                #8
                Re: Westinghouse 22w3 DAC 19M009

                Brightness and contrast have no effect on the backlight, they only adjust the video signal to the lcd itself. You would need a backlight adjustment in the menu and if its not there you can't turn it down without modifying the circuit. Placing your finger on the transformer and looking at the corona is not going to tell much, It could indicate a slightly higher voltage due to less current draw by the lamps, If one set of lamps is bad the other set is on its way out also.
                As for the chirping, it may be a weak capacitor in the power supply, remove and check them or try relacing them.

                Comment


                  #9
                  Re: Westinghouse 22w3 DAC 19M009

                  R_J, thanks for the information, although it has confused me. CapLeaker's recommendation was to lower the brightness and testing seem to prove it prevented the CCFL's from shutdown. Doesn't the brightness control the high voltage sent to the CCFL's, otherwise, why would turning down the brightness affect the time to black? Also it certainly seemed that when I turn up the brightness, the spare lamp set became brighter to my observation. So what is causing the CCFL power circuit to shutdown when brightness is set higher than 70/100? Just want to learn and hope you can better explain

                  Comment


                    #10
                    Re: Westinghouse 22w3 DAC 19M009

                    It looks like the brightness Does control the diming of the backlight. I checked the schematic for a different board and it does have an Vadj pin from the main board to control the bit3713 drive ic
                    Last edited by R_J; 01-07-2019, 02:47 PM.

                    Comment


                      #11
                      Re: Westinghouse 22w3 DAC 19M009

                      Thanks for the clarification. I too was checking the DAC-19m008 schematic
                      Code:
                      http://monitor.espec.ws/files/delta_dac-19m008_198.pdf
                      (which is closest that I can find on Internet to the DAC-19m009) and indeed on the page 6 schematic shows the Vadj input and page 3 describes the voltages for ignition and low and high brightness. Thanks again. Cheers. Brian

                      Comment


                        #12
                        Re: Westinghouse 22w3 DAC 19M009

                        I did find a cracked bulb on the upper, which was causing the screen to blank as if it was two seconds to black. Interesting that it was still lighting with a lower voltage. I order replacement bulbs from CCFL Warehouse. Actually found the correct bulb with leads in Closeout section. I replaced the two upper bulbs and now the top is brighter than the bottom! Probably means that the lower bulbs are starting to fail also, so I'll replace them next.

                        I'm also seeing a bright spot in the corners for the new bulbs, can that be the result of not getting the bulb in the right place behind all fresnels?

                        I also still have the chirping and an unsolved problem.
                        First the chirping. I'm going to try soldering any potential cold joints. But think the output transformer may have a issue. I'm just trying to figure out where to get a replacement, since the 19M088 uses one transformer not two?

                        The unsolved issue: When the monitor goes in to energy saving mode then on wake (by pushing the mouse) the image comes back but the image is shuifted left by 2 inches. On switching to VGA terminal mode and then back to XOrg mode the image shifts back to normal. The image shift doesn't happen with a Dell 1908 monitor. Is that a power issue also?

                        Comment


                          #13
                          Re: Westinghouse 22w3 DAC 19M009

                          Have you tried using the AUTO button? it should auto adjust the screen and store the settings.
                          Last edited by R_J; 04-05-2019, 04:41 PM.

                          Comment


                            #14
                            Re: Westinghouse 22w3 DAC 19M009

                            The auto button has been used many times and it doesn't affect the image position.

                            Comment


                              #15
                              Re: Westinghouse 22w3 DAC 19M009

                              So I ordered replacement caps from Digi-Key for the ones not previously replaced. I didn't want to tear down the monitor so relied on a listing from another site of the size for the caps and the Delta DAC 19M008 schematic parts list. The DAC 19M008 was built with 220uf 25v caps for c200, ce101 and ce108. But the same capacitors on the DAC 19M009 are all 330uf 25v as found when I removed the board.

                              So I need a little help. Can I use the 220uf or do I need to re-order to the 330uf caps?
                              These caps are all part of the power supply, but appear to be used for establishing power voltages. One friend who works more on timers, thought the 220uf would be ok but the ripple of the voltage wouldn't be as clean. Maybe that is one of the improvements Westinghouse requested for this 19M009 PSU compared to ViewSonic and Acer monitors using the 19M008 PSU?

                              Thanks in advance.

                              Comment


                                #16
                                Re: Westinghouse 22w3 DAC 19M009

                                Yes, you can. But it is a short term solution only, since they have to work harder. For me I'd do that in a pinch to get it going until the correct part arrives. In other words, reorder the correct caps and do the work once and right, unless you really have to cheat.

                                Comment


                                  #17
                                  Re: Westinghouse 22w3 DAC 19M009

                                  Thanks CapLeaker, I was looking at the 19M008 schematic and see that these caps are involved in the 19V circuit which feeds the hi-voltage circuit for the CCFL's and also with the 13.8 v supply which feeds the video card. One of them is in parallel with 2 1000Uf 25v caps. The one in the hi-voltage circuit actually is controlling the voltage going into the P605's, which might be why they look so overheated. None of the caps look exploded or bulged, but I just thought that age may have taken its toll and they are cheap enough to simply order, and the 220uf's can sit waiting for another project.

                                  PS Seems the 19m008 circuit is exactly the same layout as the 19m009 until you get to handing off the 19V for that circuit, then due to a single transformer the 19m008 circuit deviates from the two transformer 19m009. I wonder the 19m005 is closer for that section?

                                  I'll order the correct parts and do it right once instead of twice. Cheers

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