tag:blogger.com,1999:blog-5757177436614513342.post5919359203679186190..comments2022-04-12T15:57:55.444+02:00Comments on Alpengeist's TV (and other stuff) Repair Blog: LG 42LV4500 - Not booting - relais clicking - cold solder joint on mainboardAlpengeisthttp://www.blogger.com/profile/01348018296057576427noreply@blogger.comBlogger18125tag:blogger.com,1999:blog-5757177436614513342.post-26271102276063619472021-02-07T22:12:59.339+01:002021-02-07T22:12:59.339+01:00Thanks for replying. I'm not fully experienced...Thanks for replying. I'm not fully experienced in electronics but have been doing the basics for years, but the tracing and components are so minute, they're so hard to follow. I have followed the 12+ trace that passes through the transistors and mosfet, after which I'm lost as to where it goes next..I thought to the pins for connector but there must be somthing on the topside of board.<br />Unfortunately in the UK, it's hard to find replacement main boards but OUS boards are easy. It seems to be quite a common problem that spares have been all brought up. I rather not throw away the TV..electrical waste tooTheDragonhttps://www.blogger.com/profile/03369304434625304126noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-32795170104522580102021-02-07T19:05:41.026+01:002021-02-07T19:05:41.026+01:00I don't have any experience with this specific...I don't have any experience with this specific model. However, when the TCON does not get 12V although the power supply is fully switched on, the main board does not switch the 12V through. The reason for this can be a dead FET switch or a not fully booting software. If you are not experienced with measuring on component level on the mainboard and reading schematics, I suggest you replace the main board.Alpengeisthttps://www.blogger.com/profile/01348018296057576427noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-17388835845317252912021-02-07T17:05:10.698+01:002021-02-07T17:05:10.698+01:00Hi, I have a 47LW650T and found your blog by chanc...Hi, I have a 47LW650T and found your blog by chance, I read all your information and though many years old now, can anybody help please<br />I have joined so many sites and blogs trying ti fix it, but to no avail.<br />No picture no sound, no power to USB or Optical.<br />The PCB has all 3.5,12,24v voltages when on and 3.5V when on standby.<br />I jumpered the PSU as suggested here and my backlight turns on.<br />From research I realised that my TCON is not getting 12v from mainboard on pins 48-51. I tried to trace the 12v voltage but its too complex for me to figure out where exactly. There was a mention of Q505,Q506 transitors and Q507 mosfet, but Im not sure what to do next. ThxTheDragonhttps://www.blogger.com/profile/03369304434625304126noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-69069064447902852872020-12-08T21:27:50.870+01:002020-12-08T21:27:50.870+01:00Hi, greatings from Norway. stumbled over this arti...Hi, greatings from Norway. stumbled over this article when searching for ideas for mine lg lcd. And you never guess... a little solder job on L407 and is's alive!<br /><br />Many thanks for this article!!Anonymoushttps://www.blogger.com/profile/05752550158476911298noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-34941035432997119002019-10-03T18:24:17.430+02:002019-10-03T18:24:17.430+02:00Hard to believe, yet my LG 32LW4500 (made in Polan...Hard to believe, yet my LG 32LW4500 (made in Poland in June 2011) failed some 3.5 years later due to the exact same joint crack of L407! By that time it didn't cross my mind to google the net for a fix... so I got a new tv (still in use today), and I stored the LG for better times. Now, some 4 years after the failure, I was able to fix it thanks to your post here! Many thanks!!! <br /><br />P.S. In my case the glue seemed uniformly distributed along the entire side of L407, so perhaps the respective joint was insufficient flowed by the manufacturing machine.<br />PMhttps://www.blogger.com/profile/15934938773370882070noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-88886468026101548852018-11-05T10:32:06.894+01:002018-11-05T10:32:06.894+01:00Many many thanks to you, I had the same problem an...Many many thanks to you, I had the same problem and could not find (on the power board) and now, after I read it, my TV still work again.Anonymoushttps://www.blogger.com/profile/05767897202506111765noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-74271469278366828702018-08-15T10:06:28.168+02:002018-08-15T10:06:28.168+02:00Hi,
I will test this.
If it works, you are the bes...Hi,<br />I will test this.<br />If it works, you are the best.H-B Åkerströmhttps://www.blogger.com/profile/13498097568134045079noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-53982045620498294472017-12-23T15:17:45.558+01:002017-12-23T15:17:45.558+01:00Btw.:
I have a LG 42LW5400-ZA (November 2011)Btw.:<br />I have a LG 42LW5400-ZA (November 2011)Anonymoushttps://www.blogger.com/profile/06605779225210825340noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-49882656124990105652017-12-23T15:13:48.448+01:002017-12-23T15:13:48.448+01:00Thanks again to the community! Worked at first run...Thanks again to the community! Worked at first run!<br />Danke Hermann!Anonymoushttps://www.blogger.com/profile/06605779225210825340noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-66017117939069797762016-12-29T23:35:17.223+01:002016-12-29T23:35:17.223+01:00Thanks for these lines. I did it without measuring...Thanks for these lines. I did it without measuring and it worked very well!Anonymoushttps://www.blogger.com/profile/06742237526499461503noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-81463223566492698722016-06-30T16:26:49.136+02:002016-06-30T16:26:49.136+02:00That means your motherboard does not activate the ...That means your motherboard does not activate the backlight. You will have to measure your way through all power supply points on the power supply board and main board. Maybe the topology is a little different, but the problem is the same. Who knows.Alpengeisthttps://www.blogger.com/profile/01348018296057576427noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-38756861128116860542016-06-29T21:47:02.275+02:002016-06-29T21:47:02.275+02:00I got excited when I saw this but then released my...I got excited when I saw this but then released my board is a different rev. and doesn't have a L407. I do have the same 36v on the backlight though..Tdlunsfohttps://www.blogger.com/profile/16598898436659605343noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-16299904776050038982016-06-11T01:14:59.274+02:002016-06-11T01:14:59.274+02:00you are a geniuses you are a geniuses Anonymoushttps://www.blogger.com/profile/09582456130517011229noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-11888345843826059652016-05-10T16:43:44.191+02:002016-05-10T16:43:44.191+02:00Hi,
thank you very much for the detailled instruct...Hi,<br />thank you very much for the detailled instruction. On our flatscreen, which is also produced in 2011, occured the same mistake after 4,5 years.<br />Now its fixed ;-)Anonymoushttps://www.blogger.com/profile/14114012714422138790noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-65653890285985441082015-12-13T18:11:43.897+01:002015-12-13T18:11:43.897+01:00Thank you very much! I got LG 42LW4500 for repair ...Thank you very much! I got LG 42LW4500 for repair with the same symptoms. I re-soldered L407 and it started working!t-virushttps://www.blogger.com/profile/08332429947742503199noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-38653419718120195222015-11-11T21:40:02.611+01:002015-11-11T21:40:02.611+01:00You're welcome :-)You're welcome :-)Alpengeisthttps://www.blogger.com/profile/01348018296057576427noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-28028655480851567022015-11-11T17:56:28.950+01:002015-11-11T17:56:28.950+01:00Thanks a lot! I really appreciate your experiments...Thanks a lot! I really appreciate your experiments. Et voilà, it resurrected our blacked out LG.<br />Awesome!Juliushttps://www.blogger.com/profile/17837469244201194882noreply@blogger.comtag:blogger.com,1999:blog-5757177436614513342.post-45626491291638044642015-07-21T16:21:19.257+02:002015-07-21T16:21:19.257+02:00You are a fucking freak! Well done :-)You are a fucking freak! Well done :-)Markus W.https://www.blogger.com/profile/09867879560197068252noreply@blogger.com