LG 50PC5D - Shuts Off

Collapse
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • capkid
    Badcaps Legend
    • Oct 2010
    • 1339
    • United States
    #1

    LG 50PC5D - Shuts Off

    I'm working on an LG 50PC5D plasma TV that shuts off by itself. The power supply does not have any bulging caps, but I installed a cap kit as preventative maintenance. The TV stays on for a few minutes when it's cold, but it shuts off immediately if I turn it on when it's warm.

    I didn't see any cold solder joints on the power supply, and hitting various areas of the power supply with cold spray had no effect. I moved on to the main board, and I was finally able to get the TV to stay on by repeatedly spraying what the service manual calls a "filter bead" with the cold spray. Based on like components on the board, this component seemed to test fine at 0.2 ohms. I replaced a few SMD caps near the filter bead that I originally thought were causing the issue, but that obviously didn't help.

    Any ideas as to what could be causing the power supply to shut down? I was going to try replacing the filter bead if I could find a replacement, but I'm not sure whether it's the root cause. A red arrow in the upper-right portion of the attached pic points to the filter bead.
    Attached Files
    Last edited by capkid; 05-15-2013, 03:13 AM.
    LG Plasma Mal-Discharge Correction Service
    Tags: None
    • tom66
      EVs Rule
      • Apr 2011
      • 32560
      • UK
      #2
      Re: LG 50PC5D - Shuts Off

      The filter bead can get a crack and fail open circuit, so while it is failed try monitoring the voltage drop across it. In operation it should be near zero, when failed it should be high.
      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

        • martyparish
          Badcaps Veteran
          • Dec 2012
          • 313
          • United States
          #3
          Re: LG 50PC5D - Shuts Off

          This probably isn't related but just in case, here is a rework that I used to repair an LG LCD.

          The notes also show that one plasma was affected as well, although not your model.

          I'm not sure if that filter bead you are referring to is the same as the components I removed and jumped, but they were labeled "Lxxx". They had four pins, but yours don't seem to have four from what I can see in the pic.

          Anyhow, it's attached.
          Attached Files

            Comment

            • capkid
              Badcaps Legend
              • Oct 2010
              • 1339
              • United States
              #4
              Re: LG 50PC5D - Shuts Off

              Originally posted by martyparish
              This probably isn't related but just in case, here is a rework that I used to repair an LG LCD.

              The notes also show that one plasma was affected as well, although not your model.

              I'm not sure if that filter bead you are referring to is the same as the components I removed and jumped, but they were labeled "Lxxx". They had four pins, but yours don't seem to have four from what I can see in the pic.

              Anyhow, it's attached.
              Hmm, I'm not seeing any of the components mentioned. Anyway, I'll save this info for future use. Thanks.

              Originally posted by tom66
              The filter bead can get a crack and fail open circuit, so while it is failed try monitoring the voltage drop across it. In operation it should be near zero, when failed it should be high.
              I just measured across the filter bead, and I only get 0.006V on both sides. Strange. Cold spray directly on that component continues to work to keep the TV running. For comparison's sake, I checked a few other filter beads, and they measure about 5V.

              Edit: I just found an SMT cap next to the filter bead that measures 19V on one side and 0.006V on the other side. I'm thinking this might be my issue. From the service manual regarding this cap: C2012X7R105KFT 1uF 10% 25V X7
              Attached Files
              Last edited by capkid; 05-15-2013, 11:22 AM.
              LG Plasma Mal-Discharge Correction Service

                Comment

                • capkid
                  Badcaps Legend
                  • Oct 2010
                  • 1339
                  • United States
                  #5
                  Re: LG 50PC5D - Shuts Off

                  Well, the 1uF cap I pulled was fine. I replaced it anyway, but it didn't make a difference. Added pic of the TV with the back off.

                  Edit: Ugh, I started trying just about anything to see if I could get a reaction from the TV. I spun the fan by hand just for grins, and it started running on its own to my surprise; it didn't dawn on me that the fan wasn't moving previously. I work on cars on occasion, so I think I had radiator fans on the brain, which aren't always moving. The TV's been on for about five minutes now. SMH

                  Has anyone tried repairing the fan, or would it be better to replace it? I'm going to see if cleaning it helps, and I may try some silicone spray parts of it.
                  Attached Files
                  Last edited by capkid; 05-15-2013, 07:45 PM.
                  LG Plasma Mal-Discharge Correction Service

                    Comment

                    • ohmmy
                      Senior Member
                      • Jan 2013
                      • 182
                      • USA
                      #6
                      Re: LG 50PC5D - Shuts Off

                      Set your multimeter to read amps and connect your probes across the filter bead without spraying it with cold air and turn the set on. If the tv stays running that's definitely your problem just replace it or maybe simply jump it with a wire. Though they're generally used for noise suppression so it might cause issues with set on doing it that way.

                        Comment

                        • capkid
                          Badcaps Legend
                          • Oct 2010
                          • 1339
                          • United States
                          #7
                          Re: LG 50PC5D - Shuts Off

                          Originally posted by ohmmy
                          Set your multimeter to read amps and connect your probes across the filter bead without spraying it with cold air and turn the set on. If the tv stays running that's definitely your problem just replace it or maybe simply jump it with a wire. Though they're generally used for noise suppression so it might cause issues with set on doing it that way.
                          No, it was the fan. I applied some silicone spray, and it's been running for a while now.
                          Last edited by capkid; 05-15-2013, 08:27 PM.
                          LG Plasma Mal-Discharge Correction Service

                            Comment

                            Previous template Next

                            Related Topics

                            Collapse
                            • chaos-theory
                              Asrock z97x starts then shuts off after 4 seconds, sometimes more, no post
                              by chaos-theory
                              I have a really weird problem, this motherboard was working normally, someday it just started and all fans were running but didn't want to post, tried resetting bios, checking CPU and it was getting warm tried external gpu, flashed bios with programmer, but same problem.
                              Next day after several attempts the board goes into protection mode, no more staying on, I turn on the PSU fans starts directly turning, it used to not start until I press the pwr button, now it starts directly and fans spins, and shuts off after 3 seconds sometimes less, then won't start again unless I unplug the PSU and...
                              03-14-2025, 05:37 PM
                            • baglaivlad
                              A1706 820-00239 - Works, but sometimes shuts off when the charger is disconnected
                              by baglaivlad
                              Hello everybody!

                              Have in work A1706 820-00239 model. Originally no power, shorted PPBUS_G3H because of corroded C6403, C6404. Some water damage around this components, but nothing major.

                              After replacing this capacitors the laptop came back to work, I reinstalled MacOS and had no issues until I started to test Type-C ports. Sometimes the laptop shuts off immediately when some action with Type-C ports performed (charger disconnected or USB device inserted/disconnected). I checked Type-C port flexes, they are okay, but I cleaned them anyway. I can't see any signs of liquid...
                              11-20-2024, 08:14 AM
                            • samuelphirik
                              Dell inspiron 15 7567 sudden shuts down
                              by samuelphirik
                              Hi. I have a pre-owned Dell Inspiron 15 7567. It worked fine
                              During the first 3 days of owning it until Dell Update software popped a notification about a latest Bios version 1.15.0 and latest Intel ME Software update of which I updated. It rebooted and firstly, Upgraded Bios from version 1.8.1 to 1.15.0 then it started upgrading Intel ME firmware. After that update, my laptop shuts down without notice (Like thermal shutdown)
                              I checked Thermal Paste on the processor and the Graphics Chip and it was dry. Replacing thermal paste has not helped me.
                              Now I've noticed that laptop...
                              07-02-2023, 05:45 AM
                            • nickgronk
                              Hisense 55H6570F boots, loads then shuts down -
                              by nickgronk
                              I have a Hisense 55H6570F that gets the the boot loading screen for android and then shuts down. Oddly I hear a crackle on the mainboard as shown in the picture - nothing looks blown. The tv will boot every time, but when it reaches the loading statge of the anroid logo you can hear crackling on the board and it shuts down. What am I looking for (other than buying a new set) ? Inside the square is where I hear the crackling

                              ...
                              08-05-2024, 11:02 AM
                            • huzo
                              HP Omen shuts down when loading OS
                              by huzo
                              The model is 15ec-1061nm
                              Board number is DAG3EDMB8D0​

                              SO i turn the laptop on , and as soon as it starts booting from disk, from usb, windows,linux,HBCD,anything i boot it just turns off....while in bios menu or in linux boot menu it stays on normally...It's like when it starts to use graphics it shuts down...But i measured 0.72V while working on the GPU power line,no excess heat is comming from GPU or CPU, i even removed the heatsink and turned the laptop on and everything worked fine, got a bit hot, fan span to full speed, but it worked like that for few minutes in bios...
                              10-29-2024, 12:05 AM
                            • Loading...
                            • No more items.
                            Working...