old LG 47LE8900 not turning on

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • ioanban
    Member
    • Dec 2020
    • 47
    • uk

    #1

    old LG 47LE8900 not turning on

    Hi guys,
    I've just received an 10 years smart LG 47LE8900 from a friend and i can't seem to find out why i don't have any image or sound . It has only stand-by light .
    I have checked all voltages on the power board, I have cleaned all ribbon cables, i have checked all fuses , i have done a visual inspection on all capacitor and they look ok.

    I've attached some pictures with all the boards.
    Give me some idea's what can I do to get it working again.

    Thank you,
    Attached Files
    Last edited by SMDFlea; 09-12-2021, 07:47 AM. Reason: LG 47LE8900
  • Davi.p
    Hobbist Tech
    • Sep 2009
    • 4281
    • Italy - Milan

    #2
    Re: old LG not turning on

    Very often these LG suffers from bad CPU soldering. You need to try a reballing from a specialized center, this is one of the best models from LG so it will worth some spending, after made it a new bigger heatsink is suggested, or a fan.. it is not truly old for me..

    Comment

    • Th3_uN1Qu3
      Believe in
      • Jul 2010
      • 6031
      • Romania

      #3
      Re: old LG not turning on

      They usually do start up if the BGA soldering is bad. Disconnect the cable between main board and tcon. Does it power up then?
      Originally posted by PeteS in CA
      Remember that by the time consequences of a short-sighted decision are experienced, the idiot who made the bad decision may have already been promoted or moved on to a better job at another company.
      A working TV? How boring!

      Comment

      • Davi.p
        Hobbist Tech
        • Sep 2009
        • 4281
        • Italy - Milan

        #4
        Re: old LG 47LE8900 not turning on

        Are you referring to this particular model? Because in other LG it doesn't start..
        A quetion, when you push power button does it makes some status led blinks?
        Last edited by Davi.p; 09-12-2021, 08:42 AM.

        Comment

        • Th3_uN1Qu3
          Believe in
          • Jul 2010
          • 6031
          • Romania

          #5
          Re: old LG 47LE8900 not turning on

          The couple I had to work on would power up from standby but had no picture, no sound.
          Originally posted by PeteS in CA
          Remember that by the time consequences of a short-sighted decision are experienced, the idiot who made the bad decision may have already been promoted or moved on to a better job at another company.
          A working TV? How boring!

          Comment

          • ioanban
            Member
            • Dec 2020
            • 47
            • uk

            #6
            Re: old LG 47LE8900 not turning on

            Originally posted by Davi.p
            Are you referring to this particular model? Because in other LG it doesn't start..
            A quetion, when you push power button does it makes some status led blinks?
            I'm talking about this particular model 47LE8900 when i push the power button it turns the front touch buttons on and the logo, nothing else. No backing light or anything else.

            Comment

            • ioanban
              Member
              • Dec 2020
              • 47
              • uk

              #7
              Re: old LG 47LE8900 not turning on

              Originally posted by Th3_uN1Qu3
              The couple I had to work on would power up from standby but had no picture, no sound.
              Mine power's up but i dont have picture or sound, it might be the same problem !
              What was the solution ?

              Comment

              • ioanban
                Member
                • Dec 2020
                • 47
                • uk

                #8
                Re: old LG not turning on

                Originally posted by Th3_uN1Qu3
                They usually do start up if the BGA soldering is bad. Disconnect the cable between main board and tcon. Does it power up then?
                I've tried but it stays the same

                Comment

                • Davi.p
                  Hobbist Tech
                  • Sep 2009
                  • 4281
                  • Italy - Milan

                  #9
                  Re: old LG 47LE8900 not turning on

                  Does the lights blinks or stays on for some seconds and then shuts off? Anyway this doesn't change much, i confirm the diagnosis.

                  Comment

                  • neilc6
                    Badcaps Legend
                    • Nov 2015
                    • 1550
                    • Canada

                    #10
                    Re: old LG 47LE8900 not turning on

                    LE, LV, LW, and LS series suffers from bad bgas. Lot of ebay repair services if you google your model. To confirm, you can heat up the cpu with a hair dryer before plugging in.

                    Comment

                    • ioanban
                      Member
                      • Dec 2020
                      • 47
                      • uk

                      #11
                      Re: old LG 47LE8900 not turning on

                      Originally posted by Davi.p
                      Does the lights blinks or stays on for some seconds and then shuts off? Anyway this doesn't change much, i confirm the diagnosis.
                      Yes,
                      The lights are staying on. No blinking .

                      Comment

                      • ioanban
                        Member
                        • Dec 2020
                        • 47
                        • uk

                        #12
                        Re: old LG 47LE8900 not turning on

                        Originally posted by neilc6
                        LE, LV, LW, and LS series suffers from bad bgas. Lot of ebay repair services if you google your model. To confirm, you can heat up the cpu with a hair dryer before plugging in.
                        I will try to get it heated at around 200 degrees and see if that works. Thank you

                        Comment

                        • ioanban
                          Member
                          • Dec 2020
                          • 47
                          • uk

                          #13
                          Re: old LG 47LE8900 not turning on

                          SOLVED !
                          I have backed the main board at 200 degrees Celsius for about 10 minutes and after i left it cool down I got it back in the tv and i was pleasantly surprised to see that it works (I have done it before with other main board without success ) .

                          Thank you for the support guys!

                          Comment

                          • Davi.p
                            Hobbist Tech
                            • Sep 2009
                            • 4281
                            • Italy - Milan

                            #14
                            Re: old LG 47LE8900 not turning on

                            Ley us to know when the problem will return eventually..

                            Comment

                            • Th3_uN1Qu3
                              Believe in
                              • Jul 2010
                              • 6031
                              • Romania

                              #15
                              Re: old LG 47LE8900 not turning on

                              I can source replacement processors for these, the BGA rework side of things is up to you though as I no longer have a rework station.
                              Originally posted by PeteS in CA
                              Remember that by the time consequences of a short-sighted decision are experienced, the idiot who made the bad decision may have already been promoted or moved on to a better job at another company.
                              A working TV? How boring!

                              Comment

                              • Davi.p
                                Hobbist Tech
                                • Sep 2009
                                • 4281
                                • Italy - Milan

                                #16
                                Re: old LG 47LE8900 not turning on

                                The unique the processors that you find are probably second hand..

                                Comment

                                Related Topics

                                Collapse

                                • gadgettree
                                  Acer Nitro AN517-52 FH51M LA-J871P Works on battery only. Won't charge.
                                  by gadgettree
                                  Hi there,

                                  I am having trouble diagnosing this gaming laptop.
                                  The laptop does not power on with AC Power only. The battery also does not charge. The laptop turns on when the battery is plugged in, regardless of whether or not the charger is plugged in until the battery dies of course.
                                  So something is stopping adapter power from getting to the laptop. I checked Adapdet to make sure that the motherboard knows when the adapter is plugged in. That works fine.



                                  I suspect the first Mosfet isn't turning on but I am unsure how to properly diagnose that...
                                  02-28-2024, 05:27 PM
                                • proxneo
                                  iPad A2197 no power, A10 and other IC become warm, only 0.5A charge
                                  by proxneo
                                  Dear reader

                                  TL;DR: iPad not turning on, A10 and power IC become (very) warm when attempted to turn on but this power-on cycle has a 'cooldown' period wherein powering on doesn't work, does not take more than 0.5A charge.

                                  I am working on an iPad 7th generation 2197 from >2019 with no / limited charging and no boot issues. It is a refurbished purchase made in 2021. It appears the 'refurbish' company has either done prior motherboard work (all protective component shield layers are gone) or is one of the many trash refurbish companies (little screen adhesive left, component...
                                  12-01-2023, 04:14 AM
                                • flibidy
                                  Magnum IA.100 Amplifier Switches on, No Output, Possible Input Side fault?
                                  by flibidy
                                  I have here a Magnum IA.100 which belongs to my parents.



                                  The unit powers on & when the relay kicks in, you get a pop from the speakers (this might sound weird but is usual behavior for this amp). However, you get nothing coming through it from any of the inputs & no pops and crackls from any of the controls.


                                  Because of the sound from the speaker when the amp turns on I have assumed that the output section probably works but I could be wrong & I'm not sure how to test that side of things further.


                                  What Ive done........
                                  01-01-2025, 01:26 PM
                                • Capacitorial
                                  Philips 46PFL8007K/12 - Picuture flickers on half of the screen
                                  by Capacitorial
                                  Hello guys.

                                  I recently got a TV that has the following problems:
                                  1. Sometimes it has to be turned on and off a few times, to boot up. Sometimes it starts from the first try
                                  2. When it is running normally, the right side of the screen flickers. Sometimes it is just a square of transparent white maybe a 1/3 of the right half (top right)
                                  3. The flicker is also sometimes a square that is filled with lines
                                  4. I noticed that when the TV brightness is set to max, it flickers less. I think the Standard setting is the worst where it comes more frequent
                                  5. When it runs a few minutes it gets better,
                                  ...
                                  12-17-2023, 11:11 AM
                                • pandrew
                                  Thinkpad T490 doesn't detect NVME
                                  by pandrew
                                  I have a Thinkpad T490 (NM-B901 Rev 1.0) that cannot detect an NVME M.2 SSD,
                                  but it works fine with a SATA M.2 SSD.

                                  When connecting an NVME M.2 SSD I get while booting:
                                  "2101: Detection error on HDD0 (Main HDD)"

                                  I can continue and boot a live linux distro from a USB stick, but it doesn't show up in lspci,
                                  and I don't notice any relevant error messages in dmesg.

                                  I have tried two different M.2 NVME SSDs (both working fine on a different machine),
                                  and the behavior is the same.

                                  I am pretty sure that all the important...
                                  11-13-2023, 03:04 PM
                                • Loading...
                                • No more items.
                                Working...