JVC 49cf890 - Fire TV - no picture but sound

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • dskall
    Badcaps Legend
    • Oct 2016
    • 2905
    • usa

    #41
    Re: JVC 49cf890 - Fire TV - no picture but sound

    Vone test at the round spot or caps next to it. The other is just fuse designation.
    Vone around 25v. Test both side of fuse with N on it for 12v
    Last edited by dskall; 12-05-2021, 01:32 PM.
    I assume no responsibility for any stupid suggestions I might post.

    Comment

    • lotas
      Badcaps Legend
      • Jan 2016
      • 4455
      • Russia

      #42
      Re: JVC 49cf890 - Fire TV - no picture but sound

      Originally posted by Dobsuk
      Voffe - 0V
      Vss - 0V

      Cannot find Vone and VCC AVD. Found VONE here but not sure which point to measure:
      [ATTACH]250194[/ATTACH]

      Also found few Vcc point but not AVD.

      On this 32V point i have got 0V

      [ATTACH]250195[/ATTACH]
      32V is not a dot, this is the designation of a standing fuse ("N" - 32v at 5a)
      Attached Files

      Comment

      • Dobsuk
        Senior Member
        • May 2020
        • 127
        • England

        #43
        Re: JVC 49cf890 - Fire TV - no picture but sound

        Vone - 0V

        All Vcc points are with the correct voltage. +- 0.1 but maybe because of my multimeter. For example Vcc_1.6 is 1.7 on my meter.
        1.05 -> 1.1
        1.8 -> 1.8
        3.3 -> 3.2
        Last edited by Dobsuk; 12-05-2021, 01:54 PM.

        Comment

        • lotas
          Badcaps Legend
          • Jan 2016
          • 4455
          • Russia

          #44
          Re: JVC 49cf890 - Fire TV - no picture but sound

          I wrote to you, check, ring all ceramic capacitors with a multimeter for a short circuit.
          Attached Files

          Comment

          • Dobsuk
            Senior Member
            • May 2020
            • 127
            • England

            #45
            Re: JVC 49cf890 - Fire TV - no picture but sound

            Originally posted by lotas
            I wrote to you, check, ring all ceramic capacitors with a multimeter for a short circuit.
            I did that already. No shorts...

            Comment

            • dskall
              Badcaps Legend
              • Oct 2016
              • 2905
              • usa

              #46
              Re: JVC 49cf890 - Fire TV - no picture but sound

              Vone is important voltage. If it is not there you will have no picture.
              I assume no responsibility for any stupid suggestions I might post.

              Comment

              • Dobsuk
                Senior Member
                • May 2020
                • 127
                • England

                #47
                Re: JVC 49cf890 - Fire TV - no picture but sound

                Originally posted by dskall
                Vone is important voltage. If it is not there you will have no picture.
                So, i checked it few times - it is not there

                Comment

                • lotas
                  Badcaps Legend
                  • Jan 2016
                  • 4455
                  • Russia

                  #48
                  Re: JVC 49cf890 - Fire TV - no picture but sound

                  Originally posted by Dobsuk
                  So, i checked it few times - it is not there
                  Is there tension at these points?
                  Attached Files

                  Comment

                  • Dobsuk
                    Senior Member
                    • May 2020
                    • 127
                    • England

                    #49
                    Re: JVC 49cf890 - Fire TV - no picture but sound

                    Is there tension at these points?
                    No - 0V

                    Comment

                    • dskall
                      Badcaps Legend
                      • Oct 2016
                      • 2905
                      • usa

                      #50
                      Re: JVC 49cf890 - Fire TV - no picture but sound

                      Maybe you can list your voltages so we don't have to hunt though posts to figure out what voltages you have and what are missing.
                      I assume no responsibility for any stupid suggestions I might post.

                      Comment

                      • Dobsuk
                        Senior Member
                        • May 2020
                        • 127
                        • England

                        #51
                        Re: JVC 49cf890 - Fire TV - no picture but sound

                        Voffe - 0V
                        Vss - 0V
                        Vone - 0V
                        Vcc_1.6 -> 1.7
                        Vcc_1.05 -> 1.1
                        Vcc_1.8 -> 1.8
                        Vcc_3.3 -> 3.2

                        Comment

                        • dskall
                          Badcaps Legend
                          • Oct 2016
                          • 2905
                          • usa

                          #52
                          Re: JVC 49cf890 - Fire TV - no picture but sound

                          There also is an AVVD test point on left side of your main chip.
                          I assume no responsibility for any stupid suggestions I might post.

                          Comment

                          • Dobsuk
                            Senior Member
                            • May 2020
                            • 127
                            • England

                            #53
                            Re: JVC 49cf890 - Fire TV - no picture but sound

                            Originally posted by dskall
                            There also is an AVVD test point on left side of your main chip.
                            Excuse my incompetence but i cannot see any AVVD test points

                            Comment

                            • dskall
                              Badcaps Legend
                              • Oct 2016
                              • 2905
                              • usa

                              #54
                              Re: JVC 49cf890 - Fire TV - no picture but sound

                              Post #35 first picture between label and caps look like AVVD. If you have no voltage there, I would say you have a bad power chip.
                              I assume no responsibility for any stupid suggestions I might post.

                              Comment

                              • Dobsuk
                                Senior Member
                                • May 2020
                                • 127
                                • England

                                #55
                                Re: JVC 49cf890 - Fire TV - no picture but sound

                                Happy New Year to all. Sorry but I was away for few weeks.

                                Originally posted by dskall
                                Post #35 first picture between label and caps look like AVVD. If you have no voltage there, I would say you have a bad power chip.
                                AVVD - 1.7V

                                Comment

                                • Dobsuk
                                  Senior Member
                                  • May 2020
                                  • 127
                                  • England

                                  #56
                                  Re: JVC 49cf890 - Fire TV - no picture but sound

                                  It will be sold as spare. Thank you all.

                                  Comment

                                  Related Topics

                                  Collapse

                                  • TR103
                                    Samsung TV model UE50TU: rebooting, backlight, sound, but no picture
                                    by TR103
                                    Hi, I have a Samsung UE50TU with:
                                    - sound and backlight, but no picture
                                    - when it arrived, it had a picture for a few seconds
                                    - it keeps rebooting
                                    - without ribbon cable between the two panel boards, it does not reboot but I have no picture
                                    - without cable between mainboard and lcd panel, it does not reboot (but obviously i have no picture)
                                    - when i try a tape fix, its keeps rebooting, unless I tape off pin 1 (the innermost pin). In that case it does not reboot but I have no picture.

                                    - without cable between mainboard and lcd panel and with a jumpered...
                                    01-22-2025, 04:12 PM
                                  • Mgiffune
                                    Samsung UN60EH6000F Black Screen, Backlight and Sound Good. Power Cycle Returns Picture
                                    by Mgiffune
                                    I have a 60 inch Samsung UN60EH6000F flatscreen TV. The screen went black a few months ago Sound is good, backlight is good, no menu. I replaced the TCon board with a used board purchased from Ebay. It worked fine for a 3-4 months, then the screen started ‘fading' back. Once again, sound is good, backlight is good, no menu. However, this time the picture looks fine for about 10-15 minutes, then fades back. If I power cycle the TV, the display reappears, for another 10-15 minutes, then fades black again. Repeatable ever time.

                                    I ordered a supposedly ‘new' Tcon board this time, and
                                    ...
                                    06-09-2024, 10:28 AM
                                  • Ierwin
                                    Samsung UE60KU6079 backlight okay mainboard responsive, no picture, no sound
                                    by Ierwin
                                    Hello everyone,
                                    Ive got a UE60KU6079 on the workbench that is giving me some headaches trying to troubleshoot.
                                    The previous owner stated that there had been white dots on the screen which from the description sounded like some lenses fell of the backlight LEDs.
                                    He had opened the TV from the back, trying to get to the backlight, supposedly gave up, reassebled everything and gave the TV to me.
                                    I expected the worst like ripped COF cables or a cracked panel but could not find anything like that yet.
                                    Anyway I still fully expect that there has been something seriously damaged...
                                    05-13-2025, 03:31 PM
                                  • jchang
                                    Samsung UN70NU6900F no picture and no sound
                                    by jchang
                                    Hi all

                                    I was just given a Samsung TV with the issue. I read various threads and videos and attempted the ribbon tape method to gain an image, but no luck.



                                    Symptom:
                                    No picture no sound.
                                    When I plug in the power cord, Backlight LED turns on for a half second and then turns off. The red LED next to the power button located center bottom flashes 2 or 3 times. When the power button is pressed after, it does the same thing.
                                    No sound at all.



                                    What I tried:
                                    1. I tried unplugging the left or right ribbon...
                                    01-09-2023, 06:28 PM
                                  • ChaosLegionnaire
                                    what i went through dealing with my mobo with dead onboard sound!
                                    by ChaosLegionnaire
                                    so i took out one of my spare gigabyte ep35-ds3r mobos from storage for use to do some cpu, ram and video card testing of stuff i bought from ebay and got for free from momaka. he bought 50 e8400 cpus for cheap from ebay some years ago and i decided to help him relieve him of some of his supply since he had waaaay too many!! what did we say about hoarding too much stuff and depriving others of them?! *cough* socialism *cough* lol!

                                    i had to blow some dust off the board and heatsinks with the datavac as i didnt clean it up before putting it in storage. after finishing...
                                    09-13-2022, 09:02 AM
                                  • Loading...
                                  • No more items.
                                  Working...