Lg 50pk250

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • VivianLarrieu
    New Member
    • Jun 2023
    • 3
    • France

    #1

    Lg 50pk250

    Hi,

    I found a LG 50PK250 but on the first test, the TV does not have image, just sound.

    I check some voltage, Va and Vs have some stability problems and I found that some soldering should be repaired. After that, Va and Vs are good.
    The D1 blinks on the controller board, the TV is live, but still no image...

    I check others voltage, all others seems good except VSC and VY. They are close of 0.
    So, I suspect the Y-Sus board have one or more components to change.

    I check all FET and found some to be replace (Q405, Q408, Q412, Q414 & Q415).

    I check all Y-Drive connectors (upper & lower) in diode mode and I do not found any problem.

    I also check the different internal voltage, FG5V, FG10V, FG11V, FG15V, FG24V and 18V are good.

    I also check the Y-Drive boards for shorts and do not find any problem (check all connectors in diode mode... long process).

    So, I order the five FET and change them.
    Then, I connect the Y-SUS board again without connecting the Y-Drive boards.
    Power-up... no VSC & VY, still around 0.
    I try again with the Y-Drive boards in case the load is not sufficient to start correctly the board.

    This time, one of the new FET (Q405) exploses....

    I suspect another problem, but I need your help to find the problem.

    Thanks
    Vivian
  • tvtimmy
    Badcaps Legend
    • Mar 2015
    • 1160
    • usa

    #2
    Re: Lg 50pk250

    The new ones are probably fakes from China. Always test new ones before installing.

    Comment

    • VivianLarrieu
      New Member
      • Jun 2023
      • 3
      • France

      #3
      Re: Lg 50pk250

      Thanks for the advice.
      Where do you recommand to purchase these 30F124 ?
      I found only some on ebay.

      Comment

      • tvtimmy
        Badcaps Legend
        • Mar 2015
        • 1160
        • usa

        #4
        Re: Lg 50pk250

        It's been along time and I can't remember who I bought them from. Ebay doesn't go that far back for me to check either. My advice is order from someone that posts a picture that looks like the original and takes returns. I explained that I know how to test them and then they refunded my money without having to send the fakes back to them.

        Comment

        • R_J
          Badcaps Legend
          • Jun 2012
          • 9535
          • Canada

          #5
          Re: Lg 50pk250

          It is also possible that when the mosfet shorted it also damaged the gate drive circuit as well.

          Comment

          Related Topics

          Collapse

          • legg
            LG 42PC3 buffer output doesn't follow YSUS
            by legg
            LG42PC3D -UD originally with green lamp but no display or audio.
            Owner says was working, then went 'pop'.
            All 5V caps bulging. replaced.
            All PSU output voltages within spec but -Vy is low on YSUS.
            One of three parallel fets between SUS_OUT and SUS_DN is zenering,
            eventually shorts DG. Replaced all 3 - -Vy now OK.

            Y scan buffer test point does not follow YSUS output below -50V

            Note: This unit seems to expect YSUS output to park at -Vy in between
            drive signal pattern periods. A replacement drive signal board confirms this....
            11-18-2021, 11:49 AM
          • Truncatedhose
            Help repair this relic? Philips 42PF7220A/37, pulsing buzz from YSUS
            by Truncatedhose
            Greetings all!

            Originally this set had the usual messed up video symptoms such as: horizontal lines, weak, grainy video, bottom and top of picture differ in intensity of problem. It also seemed to slow to turn on or show the messed up picture.

            Seemed like must be YScan/buffer board failure. Ordered buffer boards from my distributor which were supposed to be original/new and also from another distributor, I ordered the YSUS because I wanted to replace it for preventative maintenance. (also, the YSUS had a bulged cap, so there was even more reason to suspect it could...
            07-04-2018, 10:59 AM
          • zwarder
            eax61319402 50PJ350 YSUS
            by zwarder
            Hi
            Had shorted YSUS

            Q24 RPJ63F3
            C726 cap
            Q11 K3667
            R528 & R529 2.2 ohm

            replaced all of these but still trips psu VS & VA are a bit low when ysus disconnected. IC301 does look a bit burnt however

            ZSUS is also good as far as I can tell

            Anyone could help me out on this one
            10-23-2023, 08:11 AM
          • maces
            LG 60PH6608 YSUS repair
            by maces
            Hello all,

            I have a problem with my LG 60PH6608. The TV is only clicking and doesn't get started.
            I checked the power supply and measured that the 200V is shorted at the YSUS board.
            All IGBTs, the MOSFET K8A60DA and the diode D603 are shorten.
            So I replaced the parts. I checked the further parts for shorts and I was pretty sure that there is no further problem on the board.
            So I plugged it in. Directly, resistor R251 (2,2 Ohm) blowed out with a little spark. Immediately I disconnected the TV from supply.
            I checked the replaced parts (IGBTs, MOSFET...
            12-11-2022, 02:21 AM
          • goldbird78
            YSUS EBR73561201 clicking off on a LG 60PV400
            by goldbird78
            Hi all, I have a EBR73561201 Ysus board on a LG 60PV400 that clicks off after 2 seconds when powered up. I am 99% sure the problem is the YSUS board because when I power up the TV with it disconnected the tv stays on and I have tested the buffers and when the buffers are disconnected and the YSUS is powered the TV shuts down. I did replace a couple of FGPF4633 transistors that were shorted and tested all gate resistors but it still will shut down once I hook up the ribbon cable from the control board. I retested the transistors I replaced and tested the gate resistors and they seem fine. Anyone...
            10-30-2018, 06:57 AM
          • Loading...
          • No more items.
          Working...