Intermittent fault with Phillips FlatTV - bad inverter?

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  • Katch
    New Member
    • Jan 2013
    • 7
    • United Kingdom

    #1

    Intermittent fault with Phillips FlatTV - bad inverter?

    Just thought I'd ask a second opinion before getting a spare inverter for my TV.

    TV is a model 26pfl5522d - when turning on it flickers in large horizontal bands. You can see the picture but it looks like the contrast is low and the brightness high - blacks appear washed out (although over all brightness output is lower than when the fault stops)

    After a few minutes the screen pops back to normal - sometimes taking up to 10 or 15 minutes. Once this has happened the fault does not reappear until the TV has been left turned off for some time. Occasionally the fault does not occur at all.

    I can shoot a video and post on youtube if need be - my gut instinct is the inverter board.
    Last edited by Katch; 01-14-2013, 04:17 PM.
  • tom66
    EVs Rule
    • Apr 2011
    • 32560
    • UK

    #2
    Re: Intermittent fault with Phillips FlatTV - bad inverter?

    I've seen this before with the bigger brother to this, the 37PFL7662. It's a failing LCD panel, it's often easy to fix though.
    https://www.youtube.com/watch?v=purk_SyiT44

    It is not an inverter fault as far as I am aware.
    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

    • Techstar
      Tv Restoration
      • Dec 2012
      • 122
      • United Kingdom.

      #3
      Re: Intermittent fault with Phillips FlatTV - bad inverter?

      That would be a good start to post a video. The t -con boards on this tv fail
      often so does the tab bonding, if it was me and i suspected a faulty inverter i would check the inverter board with my magnifier lamp for anything obvious before ordering replacement parts. Have you done a visual inspection of the suspected inverter board yet ? Checked and cleaned connectors ? .

      Comment

      • Katch
        New Member
        • Jan 2013
        • 7
        • United Kingdom

        #4
        Re: Intermittent fault with Phillips FlatTV - bad inverter?

        Hmmm the fault in that video is not like the one I am experiencing.

        The fault with this set occurs across the entire panel - if you feed the panel a fullscreen black (by using hdmi off a laptop etc) you will see an over all washed out black and thin horizontal banding.

        As the screen warms up it seems to flicker in 3 distinct horizontal bands (roughly thirds) - the flickering is that third popping to normal for a second before going back to washed out. Then all of a sudden the whole panel pops to normal.

        EDIT - I haven't had a chance to get a look under the hood yet.

        Comment

        • tom66
          EVs Rule
          • Apr 2011
          • 32560
          • UK

          #5
          Re: Intermittent fault with Phillips FlatTV - bad inverter?

          Yes, it may not be the same fault, but the root cause is the same. It is the tab bonds on the LCD panel.

          I've seen exactly what you are talking about. It's not too difficult to fix on a 26".

          Here is my telly after making a repair to the inverter (it has same fault, shorter time though): https://www.youtube.com/watch?v=HIAYwDKwT0Y
          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

          • Katch
            New Member
            • Jan 2013
            • 7
            • United Kingdom

            #6
            Re: Intermittent fault with Phillips FlatTV - bad inverter?

            Hmmm it could be - unfortunately mine is on and warm so it won't show the fault again till I leave it off for a while.

            I'll take a video next time and check the tab bonds if I get a chance tomorrow.

            Comment

            • Katch
              New Member
              • Jan 2013
              • 7
              • United Kingdom

              #7
              Re: Intermittent fault with Phillips FlatTV - bad inverter?

              Here's an update then. Not had a chance to open the set up yet but here is a good video of my problem.

              http://youtu.be/J6SXjfrx6_U

              Comment

              • tom66
                EVs Rule
                • Apr 2011
                • 32560
                • UK

                #8
                Re: Intermittent fault with Phillips FlatTV - bad inverter?

                It looks a little like the beginnings of my problem as shown in the video.
                However there's the chance too that it's the LVDS connector.
                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

                • Katch
                  New Member
                  • Jan 2013
                  • 7
                  • United Kingdom

                  #9
                  Re: Intermittent fault with Phillips FlatTV - bad inverter?

                  so i'm opening her up now - lets see...

                  Comment

                  • Katch
                    New Member
                    • Jan 2013
                    • 7
                    • United Kingdom

                    #10
                    Re: Intermittent fault with Phillips FlatTV - bad inverter?

                    hmmmm ok - so here's what I did,

                    opened it up and put rubber shims on top of the 6 tab bonds on the top and the 3 down the left hand side.

                    Turning on - the flicker has gone.... but so has the picture. Sound works as expected...

                    Comment

                    • tom66
                      EVs Rule
                      • Apr 2011
                      • 32560
                      • UK

                      #11
                      Re: Intermittent fault with Phillips FlatTV - bad inverter?

                      You have to be very careful when working on the panel as it is easily possible to chip it or damage some of the flex ribbons. Double check your work. I chipped the edge off a 40" Sony while doing this and was greeted with some slowly fading lines, no picture remained.
                      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

                      • Katch
                        New Member
                        • Jan 2013
                        • 7
                        • United Kingdom

                        #12
                        Re: Intermittent fault with Phillips FlatTV - bad inverter?

                        have removed my shims - picture is back and not flickering.... lets see if the issue returns in a day or 2.

                        Only thing I can think of that caused the picture to disappear is that my shims were pushing too much... not sure. Lets see.

                        Comment

                        • tom66
                          EVs Rule
                          • Apr 2011
                          • 32560
                          • UK

                          #13
                          Re: Intermittent fault with Phillips FlatTV - bad inverter?

                          You just want to apply enough pressure to get the picture back but not any more.
                          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

                          • djdanielb
                            New Member
                            • Jan 2013
                            • 1
                            • Italy

                            #14
                            Re: Intermittent fault with Phillips FlatTV - bad inverter?

                            Hi people I'm Daniele.
                            Nice to mmet you !

                            I've the Philips 3PFL7662 with the famous problem showed in the post before.

                            I've just change AS15-F on T-con board

                            but no solution

                            Same problem...

                            Any idea ??

                            Many thanks

                            Daniele

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