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Olevia 242FHD-T11 no picture, but has sound

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    #41
    Re: Olevia 242FHD-T11 no picture, but has sound

    I have said before about taking a neon high voltage tester to check the y drive and buffer output.

    I have never needed it for an lcd but this may be a good time to give it a try.

    I would set something up then turn on the tv. I can deal with 400v (plasma) not 1200 as I have measured on lcds (loaded voltage).

    It would be nice to check the secondary output of the master inverter this way.

    There are as said above control wires to turn on the inverter.

    I have had some use 3 leads for this.

    a 5.0v and a think two 3v feeds

    all three needed to be hooked up for the inverter to fire up.

    This was on a smaller tv and the wires came from the main board and not the power supply (only the 24v came from the power supply)

    Just a thought.

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      #42
      Re: Olevia 242FHD-T11 no picture, but has sound

      Thanks for the thought cadiman. I don't have the neon tester you mention so I cannot conduct the test you recommend. I'm struggling to understand what I would learn from the test. If there is power going through the secondary side of the inverter, would I assume the backlights themselves are bad? Or if no power, would it be the inverter? or a bad/missing signal to the inverter? Sorry, I'm quite a bit out of my area here.

      The 5v (On/Off?) that goes to the inverter appears to originates from the main board
      (run connecting the two pins and measured continuity).

      There are two "ribbon cables" attached to the inverter that very well could be providing additional digital information to/from the inverter.

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        #43
        Re: Olevia 242FHD-T11 no picture, but has sound

        The reason for the neon tester (local hardware store $3.00 or so) is when troubleshooting electrical problems you want to split the circuit in half.

        This will eliminate half of the circuit you are working with.

        I have seen bad ccfls on the china panels now on a regular basis.

        If the neon bulb does not light up when you touch it to the secondary side of the inverter. then you know you either have a bad inverter or other issues with the signal or power and ground then the panel should be ok (maybe)

        The neon bulb works great with the y drive outputs on the buffers. and you just need to be standing on the ground with one of the test wires in your hand and the other at the buffers.

        If you don`t have two seconds to black you almost always have a bad inverter board or no 24 volt from power supply (common but you will have other issues) or no signal from mainboard (rare if you have a picture with a flashlight).

        I have had smaller tvs that had a bad ribbon cable but is was easy to see the problem.

        I will go through your posts again but I think everything was covered after a few pages.

        Good luck!

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          #44
          Re: Olevia 242FHD-T11 no picture, but has sound

          I thought this was jeepitbull`s thread?

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            #45
            Re: Olevia 242FHD-T11 no picture, but has sound

            There is 3 pages now to this, you must have only read page 1 before you replied cadilacman :p

            This neon tester tool intrigues me and i will search for it next time at the hardware store, for my tv repairing needs lol

            The person who most recent posts are about is WayneI, and his tv does not have a picture when he uses a flashlight, or hes got his video source switched to something with no signal so he cant tell, takes forever to start these damn olevia tvs (like 30 seconds), so maybe he hasnt done a good test of whether the screen is working.

            Porbably be a good idea to shine flashlight at the center of screen, then turn tv on, watch for olevia logo after 10 seconds, then after 30 seconds press menu on remote, the menu is usually in center also.
            Fixed so far 12 lcd's , 1 plasmas, 5 monitors, 0 dlp's (plan to keep the dlps at 0). and 3 atx power supplies, and 2 motherboards.

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              #46
              Re: Olevia 242FHD-T11 no picture, but has sound

              Thanks for the reply cashkennedy-- You are absolutely right that this Olevia takes a looooong time to come on. I have it connected to an antenna so I should be getting a picture if I get sound. I ordered a new rectifier for my old power supply board and it just came in so I may try to solder it in tomorrow and see what happens when I install that (on the off chance that something was wrong with the replacement PS that I bought -- not holding my breath).
              I also am curious about the neon test that cadiman described (I couldn't locate a tester at Harbor Freight -- may have to try a real hardware store, although I may not know exactly what I'm looking for). I'm somewhat afraid this TV has multiple problems from when the PS failed: no backlight, no picture. The main board and PS seem like they could be a common cause of both problems -- but I'm wondering why the master inverter appears to 'load' the 5v supply.

              I appologize for 'Hi-jacking' jeepitbull's thread -- but the problems seemed so similiar that I thought it may be related.

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                #47
                Re: Olevia 242FHD-T11 no picture, but has sound

                Hijacking the thread is fine, since you have similar symptoms but possibly a different problem. It helps people looking for information to have both possible fixes in the same place.

                I forgot that you get sound, which means you should have no problem doing the flash light test unless theres crazy settings set like contrast 0 , but thats very unlikely.

                Harbor Freight Tools, while a amazing place i love, has next to 0 electronics / soldering tools. They are truely pitiful in that regard. So im not surprised they dont have a neon tester. I was thinking a neon tester would use a neon tube, so accept 400-1200v input like real neon / other gas lamps. But i googled it and http://www.amazon.com/KLEIN-TOOLS-Ge...3630661&sr=8-2 is a pretty typical offering, it only works between 100-250v, so has no real advantage over a multimeter. You could use it in conjunction with some resistors i believe, but i believe you can use resistors to allow a multimeter to take higher readings as well. Aparently as multimeters are so cheap now, neon testers are mostly a thing of the past.

                The voltage dropping only when the master inverter is connected doesnt sound to bizzare, ive never tested a situation like that, but generally the slave wont turn on at all without a signal from the master. So when just the slave is connected next to no power should be used.
                Fixed so far 12 lcd's , 1 plasmas, 5 monitors, 0 dlp's (plan to keep the dlps at 0). and 3 atx power supplies, and 2 motherboards.

                Comment


                  #48
                  Re: Olevia 242FHD-T11 no picture, but has sound

                  The great thing about the neon tester is it will detect high voltage only needing one test lead. (you are the ground) put your multimeter on a 1200 volt feed and you will be needing a new one.
                  I have an industrial fluke and 1200 volts will kill it if the test lead arcs.
                  test leads need to be hooked up before turning on the power and the connections need to be good and secure.

                  The neon tester eliminates all of this and lets me know there is voltage there.

                  Again, I mostly use these on the plasma tvs for a quick check of the y and z drive boards.

                  Comment


                    #49
                    Re: Olevia 242FHD-T11 no picture, but has sound

                    I guess you use the kind thats more like a pen / screw driver, so only has 1 probe to connect.
                    Fixed so far 12 lcd's , 1 plasmas, 5 monitors, 0 dlp's (plan to keep the dlps at 0). and 3 atx power supplies, and 2 motherboards.

                    Comment


                      #50
                      Re: Olevia 242FHD-T11 no picture, but has sound

                      It has two wires. you just hold one of them and touch the other to whatever you are testing.

                      You can NOT get shocked.

                      If the voltage is high enough it will light up without touching anything.

                      I use this for testing 480 because I don`t like both of my hands inside the panel when it`s live.

                      My industrial fluke has a red led that lights up with one probe if any voltage is present similar to the neon tester.

                      I also use neon testers to check for grounds with current flow in copper plumbing.

                      There is always some pvc pipe somewhere and a sub panel that has the neutral and the ground tied together and one copper pipe along with a 3 prong dryer.

                      Not good

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                        #51
                        Re: Olevia 242FHD-T11 no picture, but has sound

                        Well I may look for the neon tester again -- do you have a recommended source cadiman?

                        The reason I may look for one is, as you suspected cashkennedy, I do have a picture -- just no backlight. The flashlight I had been using wasn't bright enough to check for the picture --- I found a brighter flashlight and was looking for the Olevia logo as you suggested and saw it (as well as the picture from the antenna feed once it came on).

                        I wasn't able to get my old power supply going (my soldering skills and equipment both leave something to be desired) -- so I'm going to assume that the new one is good and something is wrong with either: one of the inverters, or the main board. I suspect the master inverter board since it loads down the +5v supply when I connect it (does that seem logical?).

                        I had to put the TV up for awhile as we have visitors coming and I was working on it in the living room (unacceptable to mama).

                        Any thoughts on whether I should look for a new master inverter board or do some more checking?

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                          #52
                          Re: Olevia 242FHD-T11 no picture, but has sound

                          A failed slave you will still have 2 seconds to black even if unplugged.

                          A failed master inverter you will have nothing.

                          The caps on the power supply feed the master. Make sure they are all good. Should have 24 v dc even when inverters turn on.

                          Neon tester can be found at any hardware store or lowes/ Home de-pot electrical center.

                          Mine goes from about 90 volts to around 1500 vac/dc

                          You can`t hurt it. It is just a neon bulb and two wires.

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                            #53
                            Re: Olevia 242FHD-T11 no picture, but has sound

                            I had no sound or remote at start up. Then I replaced with a brand new power supply. It then started up with the remote, sound and no picture. I took it back apart and looked at each wire position on all the harnesses. On this particular power supply, you had to use the new harnesses because the pin sockets are not the same as the original power supply. The blue wire was on the wrong side of the yellow wire on the inverter that's closest to the power supply. I pulled the blue wire out of the pin plug and installed in the correct slot and it worked. Closely check yours. It sounds like you have the same problem.
                            Last edited by Mikef12; 05-05-2012, 01:55 PM.

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                              #54
                              Re: Olevia 242FHD-T11 no picture, but has sound

                              Hello everyone, I am a new member to this forum and I want to say that I feel that this is the best way we can help each other fixed our TV problems. anyways, I also have a Olevia 242-T11 LCD TV that is having a similar problem, however I don't get sound. I checked that voltages and they all appear to be right, except the voltages to the On/Off, and B On pins. Can someone help me figure out the problem.

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