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Dynex DX-LCD32-09 Sound but no Picture

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    #41
    Re: Dynex DX-LCD32-09 Sound but no Picture

    Originally posted by gorr35 View Post
    I was affraid you'd say that!
    The results still don't make any sense, but you did clear up one thing. Your DMM shows a '1' at the left side of the display to indicate the signal is over range. Also, the meter is set on the correct range for the test.

    To clarify things, I've marked up a picture of the inverter. The transformers are numbered 1 - 14. I've labeled the terminals at the top with the letters a and b. With the meter set to the 2000 ohm range, measure the resistance from 'a' to 'b' on each transformer. Don't mess around with marking up a picture, just make a list with two columns - transformer number, resistance. And show all digits of the resistance reading.

    It is very unlikely the resistance of more than one transformer would be over range. If that happens, switch to the 20K range and recheck.

    PlainBill
    Attached Files
    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


      #42
      Re: Dynex DX-LCD32-09 Sound but no Picture

      Originally posted by PlainBill View Post
      The results still don't make any sense, but you did clear up one thing. Your DMM shows a '1' at the left side of the display to indicate the signal is over range. Also, the meter is set on the correct range for the test.

      To clarify things, I've marked up a picture of the inverter. The transformers are numbered 1 - 14. I've labeled the terminals at the top with the letters a and b. With the meter set to the 2000 ohm range, measure the resistance from 'a' to 'b' on each transformer. Don't mess around with marking up a picture, just make a list with two columns - transformer number, resistance. And show all digits of the resistance reading.

      It is very unlikely the resistance of more than one transformer would be over range. If that happens, switch to the 20K range and recheck.

      PlainBill
      If I'm doing something wrong please let me know but as pictured i'm still getting the same results on all except the ones I pointed out earlier that just read 1 .
      Attached Files

      Comment


        #43
        Re: Dynex DX-LCD32-09 Sound but no Picture

        Originally posted by gorr35 View Post
        If I'm doing something wrong please let me know but as pictured i'm still getting the same results on all except the ones I pointed out earlier that just read 1 .
        Make sure you are making contact through any coating that may be on the pins. Try at the 20K, 200K, and even the 2Meg ranges. If they are really open, it would explain the 'two seconds to black'.

        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


          #44
          Re: Dynex DX-LCD32-09 Sound but no Picture

          Originally posted by PlainBill View Post
          Make sure you are making contact through any coating that may be on the pins. Try at the 20K, 200K, and even the 2Meg ranges. If they are really open, it would explain the 'two seconds to black'.

          PlainBill
          2 seconds to black never applied here as the picture never comes up, not even for a split second, but I know what you're saying.

          Retested at the 20k setting and #5,11,12,13,14 are reading 1....all the rest are reading 0.00
          Last edited by gorr35; 09-12-2011, 11:48 PM.

          Comment


            #45
            Re: Dynex DX-LCD32-09 Sound but no Picture

            Originally posted by gorr35 View Post
            2 seconds to black never applied here as the picture never comes up, not even for a split second, but I know what you're saying.

            Retested at the 20k setting and #5,11,12,13,14 are reading 1....all the rest are reading 0.00
            Thanks for the correction. I've reviewed the thread and I'm not sure where I got that idea.

            It's time to take a different approach.

            First of all, I note that this was a 'freebie'. What was the history of it?

            Next, there aren't any really good pictures of the inverter. Could you take several, including one really good one of the area where the power and control cable connects.

            Have you checked the fuses?

            Are there any numbers 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


              #46
              Re: Dynex DX-LCD32-09 Sound but no Picture

              Originally posted by PlainBill View Post
              Thanks for the correction. I've reviewed the thread and I'm not sure where I got that idea.

              It's time to take a different approach.

              First of all, I note that this was a 'freebie'. What was the history of it?

              Next, there aren't any really good pictures of the inverter. Could you take several, including one really good one of the area where the power and control cable connects.

              Have you checked the fuses?

              Are there any numbers on the transformers?

              PlainBill
              The person who game me the TV didn't tell me anything about it other than that she got up one morning and that's how it was. As you can see from post #7 - there is nothing on the underside of the inverter. Both fuses on the inverter test at .09. As far as the transformers....there are no numbers on them, just the numbers next to them on the board - T304 etc.
              Attached Files

              Comment


                #47
                Re: Dynex DX-LCD32-09 Sound but no Picture

                Originally posted by gorr35 View Post
                The person who game me the TV didn't tell me anything about it other than that she got up one morning and that's how it was. As you can see from post #7 - there is nothing on the underside of the inverter. Both fuses on the inverter test at .09. As far as the transformers....there are no numbers on them, just the numbers next to them on the board - T304 etc.
                That makes things difficult. I do have one suggestion. Set your DMM to the 2K ohm range. Choose one of the inverter transformers. Put one probe on pin 1. Measure the resistance to each pin 2 through 6.
                2 Put the probe on pin 2, measure the resistance to each pin 3 to 7
                3. Repeat, starting at pin 3, etc,

                Post the readings.

                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


                  #48
                  Re: Dynex DX-LCD32-09 Sound but no Picture

                  [QUOTE=PlainBill;185686] Set your DMM to the 2K ohm range.

                  My meter doesn't have a 2k ohm range....did you mean 20k?

                  Comment


                    #49
                    Re: Dynex DX-LCD32-09 Sound but no Picture

                    [QUOTE=gorr35;185688]
                    Originally posted by PlainBill View Post
                    Set your DMM to the 2K ohm range.

                    My meter doesn't have a 2k ohm range....did you mean 20k?
                    2K=2000. I was doing my part for the environment by saving electrons.

                    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


                      #50
                      Re: Dynex DX-LCD32-09 Sound but no Picture

                      Originally posted by PlainBill View Post
                      That makes things difficult. I do have one suggestion. Set your DMM to the 2K ohm range. Choose one of the inverter transformers. Put one probe on pin 1. Measure the resistance to each pin 2 through 6.
                      2 Put the probe on pin 2, measure the resistance to each pin 3 to 7
                      3. Repeat, starting at pin 3, etc,

                      Post the readings.

                      PlainBill
                      Not sure if this makes any sense the way I posted it.

                      From pin 1 - p2=1, p3=002, p4=1, p5=1, p6=1
                      From pin 2 - p3=1 p4=1, p5=1, p6=1
                      From pin 3 - p4=1, p5=1, p6=1
                      From pin 4 - p5=975, p6=972
                      From pin 5 - p6=002

                      Comment


                        #51
                        Re: Dynex DX-LCD32-09 Sound but no Picture

                        Originally posted by gorr35 View Post
                        Not sure if this makes any sense the way I posted it.

                        From pin 1 - p2=1, p3=002, p4=1, p5=1, p6=1
                        From pin 2 - p3=1 p4=1, p5=1, p6=1
                        From pin 3 - p4=1, p5=1, p6=1
                        From pin 4 - p5=975, p6=972
                        From pin 5 - p6=002
                        All right!!! Nothing like giving you the wrong pins to measure.

                        Set the DMM on the 2000 ohms range and measure from P4 to P5 on each transformer and report the numbers. All readings should match to within 3% (about 29 ohms). You are hoping to find one outlier.

                        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


                          #52
                          Re: Dynex DX-LCD32-09 Sound but no Picture

                          Originally posted by PlainBill View Post
                          All right!!! Nothing like giving you the wrong pins to measure.

                          Set the DMM on the 2000 ohms range and measure from P4 to P5 on each transformer and report the numbers. All readings should match to within 3% (about 29 ohms). You are hoping to find one outlier.

                          PlainBill
                          Is there suppose to be a decimal somewhere? If looking at the previous inverter picture....from left to right. Tested p4 to p5 on each transformer.

                          @2000ohm setting - 970,987,989,989,982,982,988,997,980,985,986,994,999,973.

                          Comment


                            #53
                            Re: Dynex DX-LCD32-09 Sound but no Picture

                            Originally posted by gorr35 View Post
                            Is there suppose to be a decimal somewhere? If looking at the previous inverter picture....from left to right. Tested p4 to p5 on each transformer.

                            @2000ohm setting - 970,987,989,989,982,982,988,997,980,985,986,994,999,973.
                            Interesting - you get a range of 970 to 999 ohms, almost exactly 3%. What's more, that's a pretty consistent range of values. I would have to say those transformers are good.

                            Now we are left with the mystery of why the backlights don't come on.

                            From earlier posts, I remember there was some problem accessing certain boards. Can you make voltage readings on the inverter when the TV is (more or less) together?

                            Also, I keep remembering one TV that gave me fits. I spent hours trying to figure out why the backlights wouldn't come on. Then I turned on the TV while looking at the back of the LCD panel, and saw a very brief flash - only a fraction of a second. The inverter had a very short delay time. If I had tried turning the TV on in a darkened room, it would have been obvious.

                            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


                              #54
                              Re: Dynex DX-LCD32-09 Sound but no Picture

                              Originally posted by PlainBill View Post
                              Interesting - you get a range of 970 to 999 ohms, almost exactly 3%. What's more, that's a pretty consistent range of values. I would have to say those transformers are good.

                              Now we are left with the mystery of why the backlights don't come on.

                              From earlier posts, I remember there was some problem accessing certain boards. Can you make voltage readings on the inverter when the TV is (more or less) together?

                              Also, I keep remembering one TV that gave me fits. I spent hours trying to figure out why the backlights wouldn't come on. Then I turned on the TV while looking at the back of the LCD panel, and saw a very brief flash - only a fraction of a second. The inverter had a very short delay time. If I had tried turning the TV on in a darkened room, it would have been obvious.

                              PlainBill
                              The problem I was having with the inverter was when the inside of the TV was put together, the Mainboard sits OVER the inverter....covering the half with the power connector. So when tom66 was trying to help me, I had to keep removing this board and that board in order to test.....then put it all together again to test something on the power board. Most tests came back ok. As far as checking for a quick flash when powering on....I think I tried that already and saw nothing, but i'll try again tonight when it gets dark, and I turn off all the lights.

                              EDIT: Something else....I can't remove the metal cover for the T-Con Board without tearing down the whole panel as it looks like the cover has a lip that goes from over the board to under the panel...after taking out the screws it will lift up a little but won't come out.
                              Last edited by gorr35; 09-14-2011, 02:00 PM.

                              Comment


                                #55
                                Re: Dynex DX-LCD32-09 Sound but no Picture

                                I powered on the TV last night in the dark and nothing....not even a little flicker.

                                Comment


                                  #56
                                  Re: Dynex DX-LCD32-09 Sound but no Picture

                                  Originally posted by gorr35 View Post
                                  I powered on the TV last night in the dark and nothing....not even a little flicker.
                                  At this point I feel you have four options, none of which I'm real happy about.

                                  1. Buy a working inverter.

                                  2. Run leads from various test points so you can test the inverter while the TV is assembled.

                                  3. If this is possible, position the inverter in a location that you can access it, but obviously the CCFLs will not be connected.

                                  4. Use an external supply (or extend the power leads) and test it on the bench.

                                  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


                                    #57
                                    Re: Dynex DX-LCD32-09 Sound but no Picture

                                    I can't remember, did you check the INV_ON pin when trying to turn the TV on?
                                    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


                                      #58
                                      Re: Dynex DX-LCD32-09 Sound but no Picture

                                      I seem to have the same problem with the same type of TV. DX-LCD32-09 is the model #. Same problem as you described. Same picture with the flashlight and everything. I was able to get a hold of an inverter for $30. I just ordered it. Can you give me instructions on how to change out the inverter. Is it as simple as it looks by just unplugging the wires and placing the new inverter?

                                      Comment


                                        #59
                                        Re: Dynex DX-LCD32-09 Sound but no Picture

                                        Originally posted by finished1 View Post
                                        I seem to have the same problem with the same type of TV. DX-LCD32-09 is the model #. Same problem as you described. Same picture with the flashlight and everything. I was able to get a hold of an inverter for $30. I just ordered it. Can you give me instructions on how to change out the inverter. Is it as simple as it looks by just unplugging the wires and placing the new inverter?
                                        Yes that's pretty much it....there's just the one cable going from the power supply to the inverter. Let us know if it works!

                                        Comment


                                          #60
                                          Re: Dynex DX-LCD32-09 Sound but no Picture

                                          I have this same problem with a TV from a charitable organization i'm looking at.
                                          some of the transformers output side seem to be open.
                                          my concern is that if I spend the money on a new board, what are the chances the lights are bad? I think its not worth it to replace them as well. new 32 inch tv is cheap.
                                          if I can get a board for 50 all in then it is worth it to repair.
                                          can the lamps be tested?

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