50PK550-UD cannot be turn on

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • ezli
    New Member
    • Oct 2016
    • 9
    • Canada

    #1

    50PK550-UD cannot be turn on

    Hello Friends,

    I have a 50” LG Plasma TV bought in 2010, the picture quality and audio are all good but it was died suddenly two week ago. I have tried to troubleshoot the problem by basic diagnose, components measurement and reading lots in Badcap Forum, but I am still wondering what I should do next step. Please help if any possible suggestions, Thanks!

    TV Specifications:
    MODEL NO: 50PK550-UD; SVC CODE: 50PK550-UD.ACCALHR

    Symptoms:
    Picture of the TV initially appeared unstable, and lasted about 2 minutes then died totally when it was turn on someday in two week ago. Waiting a while and plugging it on the wall again, the TV turn on with picture and audio but it died less 1 minute. Afterwards the TV can be turn on in about 3 second if it was left untouched for long time (disconnected from power). Otherwise the TV cannot be started but with red LED on with one relay clicking when applying power.

    Basic diagnose:
    1. I have followed the “Troubleshooting Plasma TVs by tom66”, that is, disconnecting Y-sustain and Z-sustain then applying power, both testing results are same (i.e. no picture and no sound). So I think that the problem should come from the Power supply board (PCB: EAX61392501/8, PSU P/N: 60968801).
    2. By checkup the Power supply board there is not any defected soldering that is found on it.
    3. Some components measurement are listed below:
    • All fuses (F101, F302, F801) are good.
    • Resistors sound good (R305 = 0.7 Ω, R607 = 0.4 Ω, R613 = 0.4 Ω), and three white resistors (R927, 928 and 929) on top right are good also (≈10 Ω).
    • Diode 602 and 603 are good. I found that diode D304 to be a completely open both ways but it possibly because this is tested on board according a post from mustachio at https://www.badcaps.net/forum/showth...highlight=D304.
    4. Voltage measurements of the power supply connector going from power supply to main board are stable and are listed below:
    17V - It is 17.21V
    5.1V- It is 5.205V
    ERRROR_DET- It is 5.204V
    STBY – it is 5.176V
    AC_DET – it is 2.435V
    M_ON – it is 0.002V

    5. I found the capacitor C802 on my PSU, but don't know how to measure it.

    I have ordered a repair kit from ShopJimmy, but I wish to get more idea from Badcap before doing something, since I am pretty new to TV repairing.
  • TechGeek
    Computer Geek
    • Jan 2015
    • 2254
    • USA

    #2
    Re: 50PK550-UD cannot be turn on

    Disconnect everything from the PSU except the mainboard- what happens?
    Don't buy those $10 PSU "specials". They fail, and they have taken whole computers with them.

    My computer doubles as a space heater.

    Permanently Retired Systems:
    RIP Advantech UNO-3072LA (2008-2021) - Decommissioned and taken out of service permanently due to lack of software support for it. Not very likely to ever be recommissioned again.
    Asus Q550LF (Old main laptop, 2014-2022) - Decommissioned and stripped due to a myriad of problems, the main battery bloating being the final nail in the coffin.


    Kooky and Kool Systems
    - 1996 Power Macintosh 7200/120 + PC Compatibility Card - Under Restoration
    - 1993 Gateway 2000 80486DX/50 - Fully Operational/WIP
    - 2004 Athlon 64 Retro Gaming System - Indefinitely Parked
    - Main Workstation - Fully operational!

    sigpic

    Comment

    • ReeceyBurger123
      Never Give Up !
      • May 2014
      • 7325
      • Britain

      #3
      Re: 50PK550-UD cannot be turn on

      M-ON being 0v is an issue, disconnect mainboard and run test patterns via control board.
      Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

      https://www.facebook.com/Telford-Tel...7894576335359/

      Comment

      • ezli
        New Member
        • Oct 2016
        • 9
        • Canada

        #4
        Re: 50PK550-UD cannot be turn on

        Hi TechGeek and ReeceyBurger123, thank you for quickly reply! I just re-test the voltages of the power supply connector under two states:

        1. Disconnect everything from the PSU except the mainboard:
        17V - It is 17.21V
        5.1V- It is 5.205V
        ERRROR_DET- It is 5.205V
        STBY – it is 5.178V
        AC_DET – it is 2.437V
        M_ON – it is 0.002V
        The data above is almost same as the testing yesterday.


        2. Disconnect everything from the PSU:
        17V - It is 17.24V
        5.1V- It is 5.222V
        ERRROR_DET- It is 5.222V
        STBY – it is 5.222V
        AC_DET – it is 0.000V
        M_ON – it is 0.000V

        Comment

        • ReeceyBurger123
          Never Give Up !
          • May 2014
          • 7325
          • Britain

          #5
          Re: 50PK550-UD cannot be turn on

          Please run the test patterns, seems like mainboard to me already.
          Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

          https://www.facebook.com/Telford-Tel...7894576335359/

          Comment

          • ezli
            New Member
            • Oct 2016
            • 9
            • Canada

            #6
            Re: 50PK550-UD cannot be turn on

            Thank you ReeceyBurger123!

            I just learn and run the test patterns:

            Yes, with the mainboard disconnected I can see the test patterns. Does this means that the mainboard has problem? What should I do next?

            Comment

            • vinceroger69
              Badcaps Legend
              • Mar 2012
              • 6714
              • uk

              #7
              Re: 50PK550-UD cannot be turn on

              yes you will need a new mainboard whats the part number from it?

              Comment

              • ezli
                New Member
                • Oct 2016
                • 9
                • Canada

                #8
                Re: 50PK550-UD cannot be turn on

                The part number should be EAX61358603(1), it seems out of stocks everywhere.

                Comment

                • TechGeek
                  Computer Geek
                  • Jan 2015
                  • 2254
                  • USA

                  #9
                  Re: 50PK550-UD cannot be turn on

                  Quick Google search turned up this:

                  http://www.ebay.com/itm/LG-0403B-EBR...-/261782607237
                  Don't buy those $10 PSU "specials". They fail, and they have taken whole computers with them.

                  My computer doubles as a space heater.

                  Permanently Retired Systems:
                  RIP Advantech UNO-3072LA (2008-2021) - Decommissioned and taken out of service permanently due to lack of software support for it. Not very likely to ever be recommissioned again.
                  Asus Q550LF (Old main laptop, 2014-2022) - Decommissioned and stripped due to a myriad of problems, the main battery bloating being the final nail in the coffin.


                  Kooky and Kool Systems
                  - 1996 Power Macintosh 7200/120 + PC Compatibility Card - Under Restoration
                  - 1993 Gateway 2000 80486DX/50 - Fully Operational/WIP
                  - 2004 Athlon 64 Retro Gaming System - Indefinitely Parked
                  - Main Workstation - Fully operational!

                  sigpic

                  Comment

                  • vinceroger69
                    Badcaps Legend
                    • Mar 2012
                    • 6714
                    • uk

                    #10
                    Re: 50PK550-UD cannot be turn on

                    Originally posted by ezli
                    The part number should be EAX61358603(1), it seems out of stocks everywhere.
                    is there any other numbers on stickers anywhere that start with ebr etc as you also need to match those too, Have you looked too see if anyone offeres a repair service for these boards?

                    Comment

                    • ReeceyBurger123
                      Never Give Up !
                      • May 2014
                      • 7325
                      • Britain

                      #11
                      Re: 50PK550-UD cannot be turn on

                      Just type the model of the Tv in, Lg Plasma boards are mostly universal for the 50" 1080p sets as long as they have the same power connectors and are from a similar panel.
                      Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

                      https://www.facebook.com/Telford-Tel...7894576335359/

                      Comment

                      • ezli
                        New Member
                        • Oct 2016
                        • 9
                        • Canada

                        #12
                        Re: 50PK550-UD cannot be turn on

                        There is a sticker with barcode and strings "05EBR040-0001 65775302", "RH05G101L8". I have reflowed the mainboard last night (i.e. baked it in oven under 200°C about 10 min.), but it still does not work. I am going to buy a mainboard or repair it locally, and I will update if any of results. Thanks everybody's help!

                        Comment

                        • vinceroger69
                          Badcaps Legend
                          • Mar 2012
                          • 6714
                          • uk

                          #13
                          Re: 50PK550-UD cannot be turn on

                          Originally posted by ReeceyBurger123
                          Just type the model of the Tv in, Lg Plasma boards are mostly universal for the 50" 1080p sets as long as they have the same power connectors and are from a similar panel.
                          Thanks reece some handy information too know.

                          Comment

                          Related Topics

                          Collapse

                          • pajdek
                            Lenovo Y700-17ISK turn on and off
                            by pajdek
                            Hello, i have some issues with my laptop Lenovo Y700-17ISK (motherboard BY511 NM-A541), it started when i turn on the laptop, but the lcd wont turn on, i then connected it via hdmi to tv and screen was ok. So i thought maybe lcd stripe is faulty, i removed the bottom cover, disconnected main battery, reset the cmos by disconnecting battery for 1 min, then slighty move the lcd stripe. Conncted power supply and tuned on my laptop, the lcd turn on, it started to load os, then it turn off, after a second it turn on, then after like 3 seconds turn off again, and so on. Removed power supply, waited...
                            09-20-2023, 02:49 AM
                          • RdeveLabs
                            MSI GF63 THIN 11UCX (MS-16R6) LAPTOP WON'T TURN ON AFTER RESTARTING
                            by RdeveLabs
                            To all the members here...

                            Let me tell you a little bit about what happened to my laptop (MSI GF63 THIN 11UCX model: MS-16R6) that “maybe” you know how to solve this problem.

                            So before this problem happened, my laptop was running smoothly. When I wanted to restart my laptop, it looked fine at first. But after I waited for this restart process to take a long time, until finally I panicked (because the restart process did not finish plus the laptop screen only showed a black screen), I immediately pressed and held the power button to force the laptop to turn off. But...
                            05-05-2025, 04:59 AM
                          • robante15
                            Acer Aspire 4520 won't turn on after reboot
                            by robante15
                            Hello, I have an Acer Aspire 4520 from a couple of decades ago and I want to repair it solely for nostalgia.

                            It happens that when I turn it on after having been disconnected for a long time, it turns on without problems, it tells me that the BIOS has been reset and that it will load the factory settings, if I tell it to continue, the computer turns on and everything works fine.

                            The moment I turn it off and want to turn it back on a second time, or restart it and try to start it again, it no longer gives an image, and it no longer responds.

                            If I remove the...
                            04-06-2024, 06:50 PM
                          • masoksian
                            Dell latitude e7470 not turn on .power buton on off and Run Power problem
                            by masoksian
                            Hi everyone,

                            I am dealing with the problem of turning on and off my Dell e7470 notebook.

                            The battery charge light is solid white, I press the button, the power indicator and the light on the button are solid for 1-2 seconds and immediately turn off.

                            The system does not turn on, there is no post.

                            I removed the RAMs and changed them, changed the battery, RTC battery, AC adapter, removed them and waited, tried again, it does not turn on.
                            The problem continues in the same way.
                            I tried to turn on the Fn key, nothing came to the screen....
                            02-15-2025, 12:08 PM
                          • dqtech
                            lenovo x240 nm-a091 wont turn on
                            by dqtech
                            i got this laptop with no power issue....i flashed the bios and laptop can turn on and use normally....but when i shut it down and rest for few minute (2-3 minutes), it wont turn on....i have to flash bios again...any idea what is the problem?...when i shutdown and suddenly press power button to turn on, it will turn on normally....problem happen when i rest the laptop 2-3 minutes after shutdown, it will not turn on....i need to flash bios again
                            board number VIUX1 NM-A091 REV:1.0...
                            02-07-2024, 01:57 AM
                          • Loading...
                          • No more items.
                          Working...