LG 50PB560B completely dead

Collapse
X
Collapse
 
  • Page of 2
  • Time
  • Show
Clear All
new posts
Previous 1 2 template Next
  • mattpd
    Badcaps Veteran
    • Oct 2012
    • 301
    • USA
    #1

    LG 50PB560B completely dead

    NO signs of life with this one, although power supply seems to be working. Can someone check these voltages? This is with the power board out of the TV and on the bench.

    VA = 55v
    VS = 205v
    17v = 17v
    5.2v = 5.18v
    AUTO_GND = 3.5v
    M_ON = 0.63v (what's this and why is it so low?)
    AC_ON = 5v
    RL_ON = 1.13v (what's this and why is it so low?)
    17v_DET = 2.5v
    VS_ON = 0.68v (what's this and why is it so low?)
    VS_DET = 2.8v

    Main voltages seem to be present. I am concerned about the low readings though. I think they are ENABLE signals that I probably need... Can anyone enlighten me?
    Tags: None
    • mattpd
      Badcaps Veteran
      • Oct 2012
      • 301
      • USA
      #2
      Re: LG 50PB560B completely dead

      Just measured with the board installed.

      All voltages are 0v.

      If I unplug the power harness to the main board all voltages return to normal.

      Bad main?

        Comment

        • ReeceyBurger123
          Never Give Up !
          • May 2014
          • 7325
          • Britain
          #3
          Re: LG 50PB560B completely dead

          Yeah looks like mobo to me, bridge Pson to gnd and Vson to rlon see if Psu comes on.
          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

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA
              #4
              Re: LG 50PB560B completely dead

              pictures of the board and the board P/N?
              Is this your board?
              LG EAY63168601
              http://www.shopjimmy.com/lg-eay63168...upply-unit.htm
              With board by itself, are you getting close to 400VDC between the two legs of the main filter caps?
              It must be working otherwise you will not have Vs, Va, 17V if the PFC Voltage booster is not working because Vs/Va required boosted Voltage to work.
              What DCV do you get on those pins when you have the board all hooked back up?
              Last edited by budm; 02-11-2016, 03:20 PM.
              Never stop learning
              Basic LCD TV and Monitor troubleshooting guides.
              http://www.badcaps.net/forum/showthr...956#post305956

              Voltage Regulator (LDO) testing:
              http://www.badcaps.net/forum/showthr...999#post300999

              Inverter testing using old CFL:
              http://www.badcaps.net/forum/showthr...er+testing+cfl

              Tear down pictures : Hit the ">" Show Albums and stories" on the left side
              http://s807.photobucket.com/user/budm/library/

              TV Factory reset codes listing:
              http://www.badcaps.net/forum/showthread.php?t=24809

                Comment

                • mattpd
                  Badcaps Veteran
                  • Oct 2012
                  • 301
                  • USA
                  #5
                  Re: LG 50PB560B completely dead

                  Originally posted by budm
                  pictures of the board and the board P/N?
                  Is this your board?
                  LG EAY63168601
                  http://www.shopjimmy.com/lg-eay63168...upply-unit.htm
                  With board by itself, are you getting close to 400VDC between the two legs of the main filter caps?
                  It must be working otherwise you will not have Vs, Va, 17V if the PFC Voltage booster is not working because Vs/Va required boosted Voltage to work.
                  What DCV do you get on those pins when you have the board all hooked back up?
                  Yes, that is my board.

                  398v between the caps with the board out.

                  168v when I connect the main board power harness.

                  Apparently this power board is a replacement. The owner thought it would fix the problem but it did not.

                    Comment

                    • mattpd
                      Badcaps Veteran
                      • Oct 2012
                      • 301
                      • USA
                      #6
                      Re: LG 50PB560B completely dead

                      Originally posted by ReeceyBurger123
                      Yeah looks like mobo to me, bridge Pson to gnd and Vson to rlon see if Psu comes on.
                      I don't see a PSon label anywhere.

                        Comment

                        • budm
                          Badcaps Legend
                          • Feb 2010
                          • 40746
                          • USA
                          #7
                          Re: LG 50PB560B completely dead

                          Originally posted by mattpd
                          Yes, that is my board.

                          398v between the caps with the board out.

                          168v when I connect the main board power harness.

                          Apparently this power board is a replacement. The owner thought it would fix the problem but it did not.
                          OK, the PFC Voltage booster is working as I thought. The board may be using ACTIVE LO signals for the commands.
                          So those readings you took post 1 when the board is out on the bench and not connected to other boards, now we need to get the readings when all the boards are connected back in place and power is activated.
                          Last edited by budm; 02-12-2016, 09:59 AM.
                          Never stop learning
                          Basic LCD TV and Monitor troubleshooting guides.
                          http://www.badcaps.net/forum/showthr...956#post305956

                          Voltage Regulator (LDO) testing:
                          http://www.badcaps.net/forum/showthr...999#post300999

                          Inverter testing using old CFL:
                          http://www.badcaps.net/forum/showthr...er+testing+cfl

                          Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                          http://s807.photobucket.com/user/budm/library/

                          TV Factory reset codes listing:
                          http://www.badcaps.net/forum/showthread.php?t=24809

                            Comment

                            • mattpd
                              Badcaps Veteran
                              • Oct 2012
                              • 301
                              • USA
                              #8
                              Re: LG 50PB560B completely dead

                              Originally posted by budm
                              OK, the PFC Voltage booster is working as I thought. The board may be using ACTIVE LO signals for the commands.
                              So those readings you took post 1 when the board is out on the bench and not connected to other boards, now we need to get the readings when all the boards are connected back in place and power is activated.
                              Measure with everything installed.

                              VA = 0v
                              VS = 0v
                              17v = 0v
                              5.2v = 5.2v
                              AUTO_GND = 0v
                              M_ON = 0v
                              AC_ON = 5v
                              RL_ON = 0.2v
                              17v_DET = 0v
                              VS_ON = 0v
                              VS_DET = 0v

                              I pulled the main board to troubleshoot it and I am finding continuity on a bunch of the SMD caps. Do schematics for these types of boards ever get released?
                              Last edited by mattpd; 02-25-2016, 02:05 PM.

                                Comment

                                • RCA2000
                                  Senior Member
                                  • Sep 2014
                                  • 111
                                  • USA
                                  #9
                                  Re: LG 50PB560B completely dead

                                  have you UNLOADED the VS and VA lines yet--to the Y-sus and Z sus boards...and THEN checked to see what the other run voltages look line?

                                  If...after you unhook the VS lines to these boards it DOES come up...even if ONLY for a few seconds and then DROPS...THEN it indicated a Y or Z_sus problem...NOT a main (signal board) problem.

                                  If...after doing this..the other voltages do NOT return...then you DO have a bad signal board.

                                  BTW--the boost converter will NOT normally boost the voltage during standby...ONLY during RUN..on the PS.

                                    Comment

                                    • mattpd
                                      Badcaps Veteran
                                      • Oct 2012
                                      • 301
                                      • USA
                                      #10
                                      Re: LG 50PB560B completely dead

                                      Originally posted by RCA2000
                                      have you UNLOADED the VS and VA lines yet--to the Y-sus and Z sus boards...and THEN checked to see what the other run voltages look line?

                                      If...after you unhook the VS lines to these boards it DOES come up...even if ONLY for a few seconds and then DROPS...THEN it indicated a Y or Z_sus problem...NOT a main (signal board) problem.

                                      If...after doing this..the other voltages do NOT return...then you DO have a bad signal board.

                                      BTW--the boost converter will NOT normally boost the voltage during standby...ONLY during RUN..on the PS.
                                      Same result with VS/VA unhooked, must be bad main board. Any way to troubleshoot a main board? as there are none for sale for a decent price. I am detecting a short across some of the SMD caps.

                                        Comment

                                        • Diah
                                          Badcaps Legend
                                          • Feb 2013
                                          • 6376
                                          • Germany
                                          #11
                                          Re: LG 50PB560B completely dead

                                          Not main board, just focus on signal parts, you have short some where.

                                            Comment

                                            • jczarniak
                                              Senior Member
                                              • Oct 2015
                                              • 179
                                              • UK
                                              #12
                                              Re: LG 50PB560B completely dead

                                              Originally posted by mattpd
                                              Same result with VS/VA unhooked, must be bad main board. Any way to troubleshoot a main board? as there are none for sale for a decent price. I am detecting a short across some of the SMD caps.
                                              I've got a similar problem with my TV.
                                              Did you managed to fix it, please?
                                              If yes, where the problem was?
                                              Thank you.

                                                Comment

                                                • ReeceyBurger123
                                                  Never Give Up !
                                                  • May 2014
                                                  • 7325
                                                  • Britain
                                                  #13
                                                  Re: LG 50PB560B completely dead

                                                  Ignore Diah, also check Vs on signal and Rl on if they are missing the Mb is faulty. Maybe run the test patterns.
                                                  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

                                                    • jczarniak
                                                      Senior Member
                                                      • Oct 2015
                                                      • 179
                                                      • UK
                                                      #14
                                                      Re: LG 50PB560B completely dead

                                                      Originally posted by ReeceyBurger123
                                                      Ignore Diah, also check Vs on signal and Rl on if they are missing the Mb is faulty. Maybe run the test patterns.
                                                      Thank you for answer.
                                                      This is my case:
                                                      TV is not switching on, standby light appears for about 1 second after disconnecting power cable.
                                                      Power supply has got Vs and Va present, correct voltages.
                                                      Thank you for any help.

                                                        Comment

                                                        • ReeceyBurger123
                                                          Never Give Up !
                                                          • May 2014
                                                          • 7325
                                                          • Britain
                                                          #15
                                                          Re: LG 50PB560B completely dead

                                                          You can run the test patterns with the Mb disconnected. Just jumper the ext gen pins on the control board and unplug the Lvd cable and the set will power on.
                                                          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

                                                            • jczarniak
                                                              Senior Member
                                                              • Oct 2015
                                                              • 179
                                                              • UK
                                                              #16
                                                              Re: LG 50PB560B completely dead

                                                              Originally posted by ReeceyBurger123
                                                              You can run the test patterns with the Mb disconnected. Just jumper the ext gen pins on the control board and unplug the Lvd cable and the set will power on.
                                                              Thanks a lot.
                                                              Which pins these are, please?
                                                              Attached photo.
                                                              Thank you very much.
                                                              Attached Files

                                                                Comment

                                                                • cliff_hootarski
                                                                  Badcaps Veteran
                                                                  • Jul 2006
                                                                  • 411
                                                                  • USA
                                                                  #17
                                                                  Re: LG 50PB560B completely dead

                                                                  EXT AUTO GEN pins top right of the big chip in the middle.

                                                                    Comment

                                                                    • jczarniak
                                                                      Senior Member
                                                                      • Oct 2015
                                                                      • 179
                                                                      • UK
                                                                      #18
                                                                      Re: LG 50PB560B completely dead

                                                                      Originally posted by cliff_hootarski
                                                                      EXT AUTO GEN pins top right of the big chip in the middle.
                                                                      Done.
                                                                      Nothing is happening.
                                                                      Next step, please?

                                                                        Comment

                                                                        • cliff_hootarski
                                                                          Badcaps Veteran
                                                                          • Jul 2006
                                                                          • 411
                                                                          • USA
                                                                          #19
                                                                          Re: LG 50PB560B completely dead

                                                                          Did you disconnect the LVDS cable? The blue colored connector.

                                                                            Comment

                                                                            • jczarniak
                                                                              Senior Member
                                                                              • Oct 2015
                                                                              • 179
                                                                              • UK
                                                                              #20
                                                                              Re: LG 50PB560B completely dead

                                                                              Originally posted by cliff_hootarski
                                                                              Did you disconnect the LVDS cable? The blue colored connector.
                                                                              Yes, I did. Blue colored cable disconnected.
                                                                              Also checked with connected and disconnected power cable to main board.
                                                                              Still same.
                                                                              You my only hope, what's next step, please

                                                                                Comment

                                                                                Previous 1 2 template Next

                                                                                Related Topics

                                                                                Collapse
                                                                                • max-power
                                                                                  Dell E6540 laptop completely dead after dssasembly
                                                                                  by max-power
                                                                                  Hi, I disassemble my laptop to replace the speakers, to access them, you have to remove everything including the heat sink and fan, unscrew the motherboard, lift it up a bit to access the speaker wire.
                                                                                  that was not the first time I dissasemble it, i did replace the same speaker a few year ago and I repaste it last year, so I had nothing to worry about. but when I put everything back together, its completely dead.

                                                                                  After a bit of investigating, i found one pin of the status led ribbon cable that was unglued from the cable and bend touching another pin, I bend it back at his place...
                                                                                  03-24-2025, 08:49 AM
                                                                                • wangbreeze
                                                                                  T480s random shutoff and then completely dead
                                                                                  by wangbreeze
                                                                                  Hello Gurus,

                                                                                  I got a ThinkPad T480s. It was running fine but suddenly started random shut down. When it turned off, I had to push the reset pin to bring it back to life. But it got aggressively worse and became completely dead. No charging light, no life.

                                                                                  I did some initial diagnostics with just the board (no battery, nothing attached, and no CMOS battery as well)

                                                                                  Initial testing of the coil resistance seems to indicate no dead short. The only low resistance I measured was at PL701. It reads 38 ohms.
                                                                                  charger gave - 20V - ok

                                                                                  U101B
                                                                                  ...
                                                                                  02-03-2024, 04:57 PM
                                                                                • pavski
                                                                                  Completely dead MSI z490 tomahawk
                                                                                  by pavski
                                                                                  Trying to troubleshoot MSI z490 tomahawk board and would appreciate your help. The board is completely dead and shows no activity when the power button is pressed.

                                                                                  I have tried to look at the Superio, the PSIN signal seems to be correct (goes from 3.3V to 0 on button press) but the voltage on PSOUT pin is quite low. I

                                                                                  t is only 0.8V which seems to be incorrect but goes to 0 when the button is pressed.

                                                                                  Can you please let me know if this is indeed incorrect and what else should I look at next?

                                                                                  Thanks!
                                                                                  06-02-2024, 02:42 PM
                                                                                • Andreasbest
                                                                                  Lenovo Thinkpad T14s completely dead.
                                                                                  by Andreasbest
                                                                                  Hello.
                                                                                  I received a T14s Gen1 ( NM-C891 motherboard ) that is completely dead, no indication of life at all.
                                                                                  I tried hard reset without RTC battery and short both pins of it for 1 minute but no luck.
                                                                                  Since it's type C connector i have no idea what to measure or where to inject voltage, so any advice are welcomed
                                                                                  Thank you in advance!


                                                                                  Schematic & boardview -> https://www.badcaps.net/forum/troubl...cfc-nm-c891-sc...
                                                                                  03-19-2024, 03:18 AM
                                                                                • armini
                                                                                  18VDC PSU completely dead - ZD-915 desoldering station
                                                                                  by armini
                                                                                  Hi everyone!

                                                                                  Three years ago I got a ZD-915 desoldering station which failed just after a few months of light use. During a short desoldering session, the station simply shut down, and since then it has been completely dead and unresponsive. The failure was silent, without any pops.

                                                                                  Due to a lack of time, I set it aside and didn't look at it.

                                                                                  Yesterday, I took it apart and did some basic measurements. The 18v terminal shows 0v. In addition, there is no visible damage to the board itself.

                                                                                  According to replies in 18VDC PSU has dropped to...
                                                                                  04-25-2023, 07:49 AM
                                                                                • Loading...
                                                                                • No more items.
                                                                                Working...