LG 50PM670S no image

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • dick_barton
    Badcaps Legend
    • Aug 2015
    • 6643
    • Wales

    #21
    Re: LG 50PM670S no image

    You could try Ohms Supplies and see if they can offer a substitute.
    http://www.ohmsupplies.co.uk
    Willing to help but I'm no expert.

    Comment

    • tietoharrastelija
      Member
      • May 2019
      • 24
      • Finland

      #22
      Re: LG 50PM670S no image

      Ah, loose ribbon.

      What is correct -VY (I got positive Voltage on multimeter) and +VSC?

      I know that VA is 55v and VS 205V

      Comment

      • tietoharrastelija
        Member
        • May 2019
        • 24
        • Finland

        #23
        Re: LG 50PM670S no image

        Measured voltages DMM:

        -VY = 190v

        VSC = 143v

        VS = 204v

        VA = 54V

        VZB = 150V

        Are these right? When I plug HDMI cable from computer to TV I heard sound but no picture I touched white square resistor on Y sus board, it was bit warm..

        Comment

        • dick_barton
          Badcaps Legend
          • Aug 2015
          • 6643
          • Wales

          #24
          Re: LG 50PM670S no image

          Disconnect the ribbon cable from the mainboard to the logic board and connect the pins on the logic board as in post #4. Then power on.
          Willing to help but I'm no expert.

          Comment

          • tietoharrastelija
            Member
            • May 2019
            • 24
            • Finland

            #25
            Re: LG 50PM670S no image

            Originally posted by dick_barton
            Disconnect the ribbon cable from the mainboard to the logic board and connect the pins on the logic board as in post #4. Then power on.
            Tested that but still no picture.. (used small wire and removed LVDS cable)

            Comment

            • dick_barton
              Badcaps Legend
              • Aug 2015
              • 6643
              • Wales

              #26
              Re: LG 50PM670S no image

              Have you carried out the test since you did the last repair in post #17

              What is the blink rate of the led on the logic board?
              Last edited by dick_barton; 05-02-2020, 04:39 AM.
              Willing to help but I'm no expert.

              Comment

              • tietoharrastelija
                Member
                • May 2019
                • 24
                • Finland

                #27
                Re: LG 50PM670S no image

                Originally posted by dick_barton
                Have you carried out the test since you did the last repair in post #17

                What is the blink rate of the led on the logic board?
                https://photos.google.com/share/AF1Q...pQMW81YURORUdR

                Link to video where green led blinking. (End of video led blinking better, sorry for background noise)

                Comment

                • dick_barton
                  Badcaps Legend
                  • Aug 2015
                  • 6643
                  • Wales

                  #28
                  Re: LG 50PM670S no image

                  The blinking rate I believe should be an equal on/off period which the video shows that it is not.
                  It looks as though it is blinking 1 long and 2 short blinks and then repeating.

                  Unfortunately although I know that the blink rate is wrong I don't know what it points towards. Perhaps someone else could offer advice.

                  Have you tested the Ybuffers?
                  Last edited by dick_barton; 05-02-2020, 06:54 AM.
                  Willing to help but I'm no expert.

                  Comment

                  • tietoharrastelija
                    Member
                    • May 2019
                    • 24
                    • Finland

                    #29
                    Re: LG 50PM670S no image

                    Originally posted by dick_barton
                    The blinking rate I believe should be an equal on/off period which the video shows that it is not.
                    It looks as though it is blinking 1 long and 2 short blinks and then repeating.

                    Unfortunately although I know that the blink rate is wrong I don't know what it points towards. Perhaps someone else could offer advice.

                    Have you tested the Ybuffers?
                    Tested Y buffers for shorts yesterday. Now VA is stable 55v and VS 205v (adjusted trim).

                    But -VY and VSC voltage now changes strange and show unrealistic voltages, under 100v and over 200v (I have cheap multimeter). Maybe something causes ripple? Some capacitor?

                    Comment

                    • tietoharrastelija
                      Member
                      • May 2019
                      • 24
                      • Finland

                      #30
                      Re: LG 50PM670S no image

                      Now -vy output about 70v (trimmer not changing) something wierd.. Tested without panel flex cables also (but then Voltage was 0v)

                      Comment

                      • tietoharrastelija
                        Member
                        • May 2019
                        • 24
                        • Finland

                        #31
                        Re: LG 50PM670S no image

                        Tested almost all caps on y sus board:

                        C204: 25V 330uf 0.35 ohm 346 uf
                        C201: 25V 330uf 0.37 ohm 343 uf
                        C102 25V 330uf 0.35 ohm 345 uf
                        C251: 250V 47uf 0.49 ohm 49 uf
                        C264: 250V 47uf 0.44 ohm 49 uf
                        C257: 200V 47uf 0.58 ohm 46.58 uf
                        C303: 250V 10uf 1.6 ohm 9 uf
                        C263: 250V 10uf 2.1 ohm 10 uf
                        C151: 50v 100uf 0.20 ohm 94.07 uf
                        C213: 50v 100uf 0.19 ohm 91.03 uf
                        C209: 50v 22uf 4.5 ohm 21.66uf
                        C101: 50v 100uf (once replaced) 0.28 ohm 102.4uf
                        C256: 50v 22uf 6.3 ohm 20.75uf (here's something when ohms increases over time while being in the meter?)
                        C134: 250v 220uf (not tested)
                        C137: 250v 220uf (not tested)
                        C137: 250v 220uf (not tested)
                        C216: 50v 100uf 0.02 ohm 105.3 uf
                        C210: 50v 100uf (once replaced) 0.32 ohm 102.9uf
                        C214: 50v 100uf (once replaced) 0.27 ohm 102.7uf
                        C305: 25v 47uf (once replaced)

                        What caps needed / is good to replace?

                        Comment

                        • dick_barton
                          Badcaps Legend
                          • Aug 2015
                          • 6643
                          • Wales

                          #32
                          Re: LG 50PM670S no image

                          Here's a guide from an ESR meter table.
                          Attached Files
                          Willing to help but I'm no expert.

                          Comment

                          • tietoharrastelija
                            Member
                            • May 2019
                            • 24
                            • Finland

                            #33
                            Re: LG 50PM670S no image

                            Maybe EAX64300301 burned, looks like one of it ic has bright spot on top when power is on tv..

                            Comment

                            • dick_barton
                              Badcaps Legend
                              • Aug 2015
                              • 6643
                              • Wales

                              #34
                              Re: LG 50PM670S no image

                              Originally posted by tietoharrastelija
                              Maybe EAX64300301 burned, looks like one of it ic has bright spot on top when power is on tv..
                              Do you have a picture of it?
                              Willing to help but I'm no expert.

                              Comment

                              • Hamie
                                Badcaps Legend
                                • Apr 2014
                                • 1383
                                • UK

                                #35
                                Re: LG 50PM670S no image

                                Dont think it's the caps. Itll likely be a cold or cracked joint. Check the pins on those transformers.

                                Comment

                                Related Topics

                                Collapse

                                • Tynan Dill
                                  Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?
                                  by Tynan Dill
                                  I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.

                                  Upon bringing it home and plugging it up, it showed a standby light.

                                  I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.

                                  The screen seems to blackout and stay black, but with a flashlight I can see the display.

                                  With my Playstation 4 connected via HDMI, and running a game I can hear sound.

                                  Assuming...
                                  11-22-2024, 01:46 PM
                                • m1ch43lzm
                                  HP Pavilion 15-eh Board DAG7HAMB8F0 - CPU throttling to 0.4GHz (PROCHOT_EXT) and black screen
                                  by m1ch43lzm
                                  Hi, this is my personal laptop, which the original board (lets call it Board A) blew up PU8700 (TPS51486), making a hole on the board, i had left the laptop at my desk one day with the battery fully charged and didn't touch it for a week, but when i tried to turn it on it didn't
                                  Thought the battery was dead, so i plugged in the charger then tried to power on, the power LED blinked once, charged LED still orange, unplugged the charger, plugged in again and I noticed the "magic smoke" smell, so i unplugged the charger, removed the back cover and saw the blown IC (the "magic...
                                  05-12-2025, 08:37 PM
                                • canadaboy25
                                  Panasonic TC-P54VT25 No image. A or D board?
                                  by canadaboy25
                                  I have a Panasonic TC-P54VT25 that will power on and prime the display but there is no image at all.

                                  The panel is primed as there is a slight glow from the entire panel. This means the problem should be logic related. The service manual also confirms this and recommends replacing the A or the D board.

                                  I have tried to get the TV to display the test sequence but I have been unable to and I don't even know if this TV has a test sequence or not. I tried following tom66's instructions in post #3 on this thread https://www.badcaps.net/forum/showthread.php?t=26790. There was...
                                  01-17-2021, 01:06 AM
                                • tuner2000i
                                  Philips 65PUS8518/12 distorted image after main board replacement
                                  by tuner2000i
                                  hello everyone,

                                  I don't normally do tv repairs but this is a case with my personal TV which got fried together with many other electronics in my house after a thunderstorm.

                                  The TV is a Philips 65PUS8518/12 which had no power. I measured and concluded that the main board was probably fried through ethernet or hdmi. I found a board with same number 715GD328-M0F-B00-005Y (I had G) but from a 55PUS8518. The TV starts but the image is doubled, distorted. I need to set the panel code which is 016 according to the sticker on the back but I can not seem to do it.

                                  ...
                                  07-15-2025, 01:15 PM
                                • huzo
                                  Dell 5590 no image on LCD,HDMI works ,the board works...
                                  by huzo
                                  The board is LA-F411P ,DELL 5590 ...

                                  The screen polarises,no backlight,no image,only black screen,tried another screen,the same,so there is no backlight,but there should be an image when i shine a lamp behind the screen,but there is none...only dark screen...when screen is connected and i press F8 to turn the image over to the external monitor, the external monitor gets coloured bars ,but when i disconnect the cable from the EDP ,the HDMI picture is good...What could be the problem? I don't have another edp cable, but i measured it with meter and it comes out good...i am baffled......
                                  02-16-2025, 03:08 PM
                                • Loading...
                                • No more items.
                                Working...