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Philips 32PFL3403d/27 LCD NO POWER

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    Philips 32PFL3403d/27 LCD NO POWER

    First off I'd like to say reading a lot of past threads have given me a better understanding of what to look for and the inner workings of my TV, but here is my issue.

    My TV set won't power on, I mean no display led, blinking ... nothing. So I went online to see what others were doing to fix their LCD. To make a long story short most individuals said the caps were bad, but not all would be, just the blown out and leaky ones. The only problem with this diagnosis was that I didn't have any bulging, leaky caps, at least not on the power board. So I just replaced the CapXon caps on the power supply board.

    The TV didn't power on but I got a momentary flash off the inverter board, so I decided to check it out. After i took off the housing over the inverter board I saw that the two caps on it were bulging and leaking (the two purple caps in the photo), so I replaced those as well.

    The TV still won't power up, but after reading about 7 hrs of threads I've conducted several test including

    continuity of the power supply fuse - good
    continuity of the power cord - good

    I've also checked if there was any current actually coming from the power supply, so I tested all the outputs from the power supply board to the inverter board. On that side of the board is 24V and the ground, which tested with a multimeter gave me 24V for each wire.

    I then checked the other side of the power board which as the 5V, 12V standby and 24V. Besides the 12V showing a voltage of 2.635 and stand by showing a voltage of 2.413 the 5V and the 24V showed up on the power supply as well as the main board.

    So now I'm hear ...


    I've included a bunch a pics

    Any help will be appreciate, thank you and sorry for the long description of my problem.

    P.S.
    1. I used generic caps for the inverter board being that I got them from an electronic shop and the guy said that they were good for the tv
    2. I used 2 caps from radio shack, 1000uf 25V and 470uf 35V, which are the exact uf but higher voltage than the original but its temp resistance isn't 105c but 85c
    Attached Files

    #2
    Re: Philips 32PFL3403d/27 LCD NO POWER

    Originally posted by shoalin View Post
    First off I'd like to say reading a lot of past threads
    Thank you for doing some research. A nice change from some of the recent twitter like, can't spell, no punctuation, threads in the last week or so. More info is much better than "it doesn't work, please help".

    I then checked the other side of the power board which as the 5V, 12V standby and 24V. Besides the 12V showing a voltage of 2.635 and stand by showing a voltage of 2.413 the 5V and the 24V showed up on the power supply as well as the main board.
    Can you re-measure just the standby pin? It should be 5V DC (in most cases). If it is reading 2.4, there is something definitely wrong.

    1. I used generic caps for the inverter board being that I got them from an electronic shop and the guy said that they were good for the tv
    2. I used 2 caps from radio shack, 1000uf 25V and 470uf 35V, which are the exact uf but higher voltage than the original but its temp resistance isn't 105c but 85c
    Your board has the distinction of having a who's who of bad caps. Capxon, generic no name, and Radio Shack general purpose caps.

    Capxon doesn't have a great reputation for making quality caps on this forum. Radio Shack does not sell low ESR caps. Generic caps are a hit/miss.

    A SMPS requires low ESR caps.

    I count 10? electrolytic capacitors on the power board. You can get quality low ESR caps like Panasonic FR, FM, FC series from digikey (if you are in the USA) in 48 hours with $2.75 shipping costs.

    We will probably recommend replacing all the electrolytic caps on the power and inverter board AFTER we do some diagnosis first. The total for you caps + shipping will probably be less than $12 USD.
    Last edited by retiredcaps; 03-27-2011, 12:09 PM.
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    Comment


      #3
      Re: Philips 32PFL3403d/27 LCD NO POWER

      Echoing much of what Retiredcaps said; Very good work giving us the information to allow us to help you. By the label for the connector to the main board, STB is the enable pin for the main power supply. Just for the fun of it, see if it changes voltage when you hit the power button. If it does, that confirms it. Certainly you will be wanting to replace all caps in the power supply with good quality caps.

      At this point it is much more likely the problem is on the Small Signal Board (Main board). The service manual can be found at Elecktrotanya. This is a fairly new set (last production in 2009). Earlier service manuals had extensive troubleshooting help; I don't know about the more recent sets.

      Correction!!! I almost missed this. The last picture is of the inverter, there almost certainly is another (master and slave). This particular inverter set is notorious for causing the symptoms you describe. Try the TV with the power leads to the inverter disconnected. If it power up (of course, there will be no light on the screen), you have identified the problem.

      Incidentally, while more information is better than not enough, this is why I usually ask for a single over-all shot of the TV.

      PlainBill
      Last edited by PlainBill; 03-27-2011, 01:36 PM.
      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


        #4
        Re: Philips 32PFL3403d/27 LCD NO POWER

        Ok, So I'm trying to repair my Philips TV, (32pfl3403d/27). I've uploaded an overall pic. I can recognize (1) CB (circuit board) from the previous post by Shoalin. Before I begin to dig, I need a little guidance, where should the inverter CB be etc.. Also, was Shoalin's TV ever fixed? What was the actual problem? I don't see any bulging or leaky caps on the CB's that are visible. I am new to this forum (basically my first forum) and I'm eager to learn. Thanks in advance for your patience and expertiese.
        Mach1

        Comment


          #5
          Re: Philips 32PFL3403d/27 LCD NO POWER

          Originally posted by Mach1 View Post
          Ok, So I'm trying to repair my Philips TV, (32pfl3403d/27). I've uploaded an overall pic. I can recognize (1) CB (circuit board) from the previous post by Shoalin. Before I begin to dig, I need a little guidance, where should the inverter CB be etc.. Also, was Shoalin's TV ever fixed? What was the actual problem? I don't see any bulging or leaky caps on the CB's that are visible. I am new to this forum (basically my first forum) and I'm eager to learn. Thanks in advance for your patience and expertiese.
          Mach1
          hi mach, welcome.

          i think you will get better guidance if you start your own thread.

          Comment


            #6
            Re: Philips 32PFL3403d/27 LCD NO POWER

            Originally posted by Mach1 View Post
            Ok, So I'm trying to repair my Philips TV, (32pfl3403d/27). I've uploaded an overall pic. I can recognize (1) CB (circuit board) from the previous post by Shoalin. Before I begin to dig, I need a little guidance, where should the inverter CB be etc.. Also, was Shoalin's TV ever fixed? What was the actual problem? I don't see any bulging or leaky caps on the CB's that are visible. I am new to this forum (basically my first forum) and I'm eager to learn. Thanks in advance for your patience and expertiese.
            Mach1
            Please do not post pictures inline. Instead use 'Manage Attachments' - below the text entry area.

            Inverter is on the left side, the power supply is in the middle, the signal board is on the right, and the tcon is at the top.

            Forget about Shoalin's TV. What is the problem with YOUR TV?

            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


              #7
              Re: Philips 32PFL3403d/27 LCD NO POWER

              PlainBill, Thank you for your advice on posing, I'll follow it. Well, my TV is absolutely blank. Nothing happens when I try to power it up, nothing. I've even had to check the outlet to see if it had power, it does. Thats about it. I can check voltages on the power supply board as a start.

              Comment


                #8
                Re: Philips 32PFL3403d/27 LCD NO POWER

                Originally posted by Mach1 View Post
                PlainBill, Thank you for your advice on posing, I'll follow it. Well, my TV is absolutely blank. Nothing happens when I try to power it up, nothing. I've even had to check the outlet to see if it had power, it does. Thats about it. I can check voltages on the power supply board as a start.
                That's a good start. You have two options;

                1. Measure the following voltages: The voltage across the main filter cap - that's the large one on the power supply. It should read about 1.4 x your AC line voltage.

                2. Take two good pictures (note the links in my signature above) of the top side and bottom side of the power supply. Crop and reduce them so the largest dimension is just under 2000 pixels. I will then suggest test points.

                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


                  #9
                  Re: Philips 32PFL3403d/27 LCD NO POWER

                  I don't know if I have a macro setting on my camera but I try to take the bast picture I can. ( I have a SONY handy cam for my digital, I'm more used to my "film" minolta 35mm, oh well, I'm a bit old school) I'll test that filter cap this evening.

                  Comment


                    #10
                    Re: Philips 32PFL3403d/27 LCD NO POWER

                    Originally posted by Mach1 View Post
                    I don't know if I have a macro setting on my camera but I try to take the bast picture I can. ( I have a SONY handy cam for my digital, I'm more used to my "film" minolta 35mm, oh well, I'm a bit old school) I'll test that filter cap this evening.
                    I understand the attraction of a 35mm SLR. Perhaps someday we will have affordable digital cameras with similar capabilities.

                    I just took a look at the pictures posted by shoalin. In addition to checking the voltage across the large cap, if you detect voltage there are a few more points to be checked. There is a 13 pin connector that goes to the inverter, and a 12 pin connector that goes to the main board. Using pin 6 for the black probe, what are the voltages on pins 10 and 11?

                    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


                      #11
                      Re: Philips 32PFL3403d/27 LCD NO POWER

                      ok, The #10 pin to gnd is 0.0vdc, the #11 pin is 5.2vdc. (on the 12 pin connector to the main board.)

                      Comment


                        #12
                        Re: Philips 32PFL3403d/27 LCD NO POWER

                        I'm suspecting that the large cap on the power supply is AC voltage?

                        Comment


                          #13
                          Re: Philips 32PFL3403d/27 LCD NO POWER

                          Originally posted by Mach1 View Post
                          I'm suspecting that the large cap on the power supply is AC voltage?
                          That is DC voltage. The Cliff's Notes version: AC power comes in, goes through a fuse and several filters to suppress noise, then to a bridge rectifier which converts it to DC. The DC is filtered (stored) by the large cap.

                          HOWEVER, that information is academic at this point. The power supply is actually two supplies on one board. The Standby supply puts out 5 volts for the standby portion of the main board. When you hit the power button, pin 10 should go to about 3.3 volts to turn on the main supply. Since that does not appear to be happening, it's time to turn our attention to the main board. And I WILL need pictures of that.

                          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


                            #14
                            Re: Philips 32PFL3403d/27 LCD NO POWER

                            I have a correction. I wanted to double check the voltages, #10 has 2.1VDC, #11 is 5.2, I'll get some pictures of the main board.

                            Comment


                              #15
                              Re: Philips 32PFL3403d/27 LCD NO POWER

                              Here's the pic I took.
                              Attached Files

                              Comment


                                #16
                                Re: Philips 32PFL3403d/27 LCD NO POWER

                                Originally posted by Mach1 View Post
                                I have a correction. I wanted to double check the voltages, #10 has 2.1VDC, #11 is 5.2, I'll get some pictures of the main board.
                                The voltage at pin 10 is worrisome. I'd expect it to be much lower (close to 0 volts) or about 3 - 3.3 volts.

                                Let's start at ground zero. With everything hooked together, measure the voltage at the following pins while someone repeatedly and slowly (once every 5-10 seconds) presses the power button. We are looking for any change in voltage, even a brief one. Pins 3, 8, 10, 11 of the 12 pin connector.

                                Also, in the upper left corner of the main board there is a green bodied cap just to the right of two black caps. The top of that green caps looks like it might be bulging. Is it? And what brands are those caps?

                                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: Philips 32PFL3403d/27 LCD NO POWER

                                  Well it took me a bit to an extra hand on my project, but here's what I found.
                                  I measured 2.0 to 2.1VDC on the 10 pin with EVERYTHING connected, and cycling the power button. I inspected every cap on the main board (the one on the right) and could not see anything bulging. The green cap to the right of the 2 black caps (they are actually green/gold) is not bulging. The brands of caps on this board are as follows: the lime green ones are "Lelon", the green/gold are "CapXon" and the black/gray are "Elite". Here are some pics:
                                  Attached Files
                                  Last edited by Mach1; 07-27-2011, 08:22 PM.

                                  Comment


                                    #18
                                    Re: Philips 32PFL3403d/27 LCD NO POWER

                                    Originally posted by Mach1 View Post
                                    Well it took me a bit to an extra hand on my project, but here's what I found.
                                    I measured 2.0 to 2.1VDC on the 10 pin with EVERYTHING connected, and cycling the power button. I inspected every cap on the main board (the one on the right) and could not see anything bulging. The green cap to the right of the 2 black caps (they are actually green/gold) is not bulging. The brands of caps on this board are as follows: the lime green ones are "Lelon", the green/gold are "CapXon" and the black/gray are "Elite". Here are some pics:
                                    Oh, good grief, three different brands of garbage caps!!!

                                    I'm not sure where to go with this. The problem seems to be on the main board. I had hoped to identify a fuse near the power connector on the main board, but none is obvious.

                                    Let's try this test. Rig yourself a 3V DC supply - two AA batteries in series will be perfect. Disconnect all of the output cables from the power supply.

                                    Connect the power supply to AC power and check the voltage from Gnd to pin 10. I would expect it to read 0 volts. If it reads 2.0 - 2.1 volts, check the voltages at pins 3 and 8. They will probably read 0 volts. If so, disconnect the AC power, and hook up the 3 volt power supply - minus to Gnd, +3 volts to pin 10. Now reconnect the AC power and measure the voltages at pins 3 and 8. If they read 24V and 12V, the power supply is probably good and we will see if we can find a problem with the main board.

                                    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


                                      #19
                                      Re: Philips 32PFL3403d/27 LCD NO POWER

                                      hello HERE the technical documentation
                                      Attached Files

                                      Comment


                                        #20
                                        Re: Philips 32PFL3403d/27 LCD NO POWER

                                        hoping that you can find the power failure

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