ps-50q97hd problem-screen turns blank

Collapse
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • charlierfc
    Senior Member
    • Mar 2013
    • 93
    • scotland
    #1

    ps-50q97hd problem-screen turns blank

    Hi all, First of all thanks for reading. I have the above plasma tv, it turns on and the screen picture is fine and sound is fine. After a random period of time the screen goes blank and just the sound remains.I opened the tv and saw no bad looking caps ect. i tested the power going to the boards on the sticker it states the vs should be 207V on 1 side i have 204V on the other i have 208V iv tried adjusting the vs output but i cant get it to 207V on both sides. Iv replaced a few caps anyway even though they read ok in the cap tester but i have no esr reader. Does anybody have any previous with this? iv seen many on google with no picture but sound or constant click but none with this fault.
    Thanks in advance.
    Tags: None
    • tom66
      EVs Rule
      • Apr 2011
      • 32560
      • UK
      #2
      Re: ps-50q97hd problem-screen turns blank

      When the fault occurs is the screen still glowing? Does the Vs drop out? 204/208V is OK for this panel.
      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

        • charlierfc
          Senior Member
          • Mar 2013
          • 93
          • scotland
          #3
          Re: ps-50q97hd problem-screen turns blank

          Hi Tom, Thanks for reply. Im waiting with the cover off for it to cut off so i can get readings.
          I took readings from the vs and va test points with all disconnected
          vs= 204 v
          va= 68 v

          Weird thing, When i put my probe on the vs test point the transformer near it seemed to make a sort of buzzing noise. Im wondering if maybe a dry joint or would this be normal?

            Comment

            • tom66
              EVs Rule
              • Apr 2011
              • 32560
              • UK
              #4
              Re: ps-50q97hd problem-screen turns blank

              These sets are well known to have cold joint issues, it wouldn't surprise me, around the main heatsinked power transistors.
              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

                • charlierfc
                  Senior Member
                  • Mar 2013
                  • 93
                  • scotland
                  #5
                  Re: ps-50q97hd problem-screen turns blank

                  Hi, I went over the joints im still waiting on the screen going blank to do further tests. Question, with the back cover off the y sus makes quite a buzz, also the transformer i recently resoldered seems to be making a buzzing sort or pulse noise. would this be normal?

                  Im thinking it is the psu? as the tv comes on normal yet after some time the power must fall cutting out the picture?

                  typcal....when i want the tv to go blank, it wont!

                    Comment

                    • tom66
                      EVs Rule
                      • Apr 2011
                      • 32560
                      • UK
                      #6
                      Re: ps-50q97hd problem-screen turns blank

                      Buzzing is normal. They are switching large currents at high frequencies.
                      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

                        • charlierfc
                          Senior Member
                          • Mar 2013
                          • 93
                          • scotland
                          #7
                          Re: ps-50q97hd problem-screen turns blank

                          Hi again, tv pic went and the reaadings remain the same, although when i came back to tv seen screen was off i tested it had stand by reading, i pressed it on and the screen remained blank with the normal readings, perhaps the tv timed itself off with no input but the tv still had no pic when turned on...

                            Comment

                            • charlierfc
                              Senior Member
                              • Mar 2013
                              • 93
                              • scotland
                              #8
                              Re: ps-50q97hd problem-screen turns blank

                              iv reset the tv with the service menu, hey never know. info-menu-mute-power. reaso i done this was because the 3rd hdmi didnt seem to work, does now, im checking the vs power seems steady though it always was as far as i know.
                              i saw a vid on youtube saying som fets fail overloading the chips on the buffer board.
                              Im wondering if one has failed and the buffer board is cutting out due to over heat?
                              tv been on 1 hour so far, screen remains ok

                                Comment

                                Previous template Next

                                Related Topics

                                Collapse
                                • Stephen
                                  MacBook Pro 14" M1 Pro Turns on functions then turns off when I plug in USB C cable
                                  by Stephen
                                  MacBook Pro 14" M1 Pro Turns on functions then turns off when I plug in USB C cable to reset the computer. I disconnect the battery fully and then reconnect it and it won't turn back on. After letting it sit for a day I plug the battery back up, and the MagSafe 3 cable and it powers on and stays ons, once I plug in a USB C cable into the port closes to the MagSafe port it turns off and the Amber light turns off and won't turn on. No water damage, nothing, I want to do a DFU restore to wipe the computer since the customer stated they did an update and ever since it just decided to not work...
                                  03-15-2024, 09:37 AM
                                • www
                                  LG L192WS-BN backlight turns off after 1 second
                                  by www
                                  I am testing an old LG L192WS-BN monitor I have that gives an image, but has a backlight issue. When you turn it on the backlight turns on 1 second and it turns off, turns on again, 1 second and it turns off and stays off. Using a flashlight I can see there's still an image.

                                  I replaced a bulged cap on the main board, but made no difference. I also got another exact same model monitor that has a broken ccfl (the connector got ripped from the panel and the main screen connector is also broken so I can't use this panel to test), tried using the main board from this one, same issue....
                                  03-24-2024, 05:26 PM
                                • hasel17
                                  CH341a can erase and read but can't write and blank check
                                  by hasel17
                                  So I am trying to repair broken thunderbolt FW on X1 Yoga Gen 2. The EEPROM chip is WINBOND 25Q80DVNIG. I already do a back-up and erase. But when I try to wrote new FW, it was successfull, but when I tried to read it, it still blank. when I try to do a blank check, it gave me instant error in address 0. I already tried two CH341A, already did the 3.3v fix mod, using AsProgrammer, NeoProgrammer, Colibri, and CH341A 1.29. But the problem still occurred. What I did wrong here? Can anyone help me? Thanks in advance. Here is the log in Colibri :

                                  Code:
                                  Checking for blank...
(Press
                                  ...
                                  10-26-2023, 06:20 AM
                                • andrhouseolly
                                  Dell Precision 5510, AAM00 LA-C361P Rev:2.0 turns on, no image.
                                  by andrhouseolly
                                  Hi.
                                  I kindly ask you to help me solve the problem.
                                  Dell Precision 5510, motherboard AAM00 LA-C361P Rev:2.0
                                  The board turns on, there is no image.
                                  Read more. When the power supply is connected, the front panel indicators light up briefly.
                                  When you press the power button, the button indicator lights up. The board works
                                  there is no image, there is no matrix initialization, there is no image on HDMI.
                                  When turned on, the fans do not spin, but when they warm up they start spinning.
                                  When you turn off the button, the fans spin up to full speed for a short...
                                  05-11-2024, 03:14 PM
                                • Egidio85
                                  Samsung UE55F8000SZ Turns on and off immediately
                                  by Egidio85
                                  good morning, I have a samsung UE55F8000SZ tv that turns on, shows the logo and turns off after 1-2 seconds.
                                  This defect happens continuously, hearing the classic click of the relay every time.

                                  Power supply board BN44-00636B

                                  disconnecting the mains and lamps from the power board always causes the same problem.
                                  Is it normal that without anything connected this power supply turns on and off cyclically?
                                  any suggestions on what to check?

                                  thanks in advance
                                  ​
                                  03-11-2025, 12:45 PM
                                • Loading...
                                • No more items.
                                Working...