LG 42LW4500-LB Need help with repair of PSU
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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 -
Re: LG 42LW4500-LB Need help with repair of PSU
Inboard and everything else and try to pit on 230vac try to set on tv and after thst i need to look for bad part ? I will try to remove the surge protection and i will check the board under voltage again if the voltage will go after because now i have voltage only on main gray filter cap i will replace the surge protection with cable for testComment
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Re: LG 42LW4500-LB Need help with repair of PSU
I need service manual for board scheme :/Comment
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Re: LG 42LW4500-LB Need help with repair of PSU
The mainboard is a common fault. Just saying its a possibility. All you need is to to heat up the large heatsink with a hair-dryer on highest heat for 2 minutes and turn on. Let me know if it doesnt work, then we can move on to psuComment
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Re: LG 42LW4500-LB Need help with repair of PSU
So far I asked you to provide simple DCV reading of the PWR-ON pin on post 26 but insisting on replacing the MOV. WHY? THE DAM THING IS NOT BAD! GET IT!
I WASTED MY TIME ON THIS THREAD WHEN YOU CANNOT EVEN FOLLOW THE INSTRUCTION!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=24809Comment
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Re: LG 42LW4500-LB Need help with repair of PSU
Someone needs a chill pillComment
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Re: LG 42LW4500-LB Need help with repair of PSU
Well what do you think?
Post 39: "Where I can found the power switch ? It will be good if you have some scheme for this board ."
Post 42 "I will try to remove the surge protection" still try to deal with MOV after all the explanation?
We are over 40 posts now an still no answer on the PWR-ON signal pin. If there is no PWR-ON form main board then the Main board will have to be checked, but at this we do not know if we have that signal or not. May be after he finds the Power switch?Last edited by budm; 11-29-2016, 10:40 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=24809Comment
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Re: LG 42LW4500-LB Need help with repair of PSU
Well what do you think?
Post 39: "Where I can found the power switch ? It will be good if you have some scheme for this board ."
Post 42 "I will try to remove the surge protection" still try to deal with MOV after all the explanation?
We are over 40 posts now an still no answer on the PWR-ON signal pin. If there is no PWR-ON form main board then the Main board will have to be checked, but at this we do not know if we have that signal or not. May be after he finds the Power switch?Comment
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Re: LG 42LW4500-LB Need help with repair of PSU
Well, you are not making any sense since as explained, the MOV is connected in parallel with the cap which you have measured 230VAC between the cap's legs, the MOV has nothing to do with the TV functioning, more likely you have disturbed bad connections or connectors that may not be seated properly or loose mounting screws holding the board to make the GND connection to the chassis, etc..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=24809Comment
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Re: LG 42LW4500-LB Need help with repair of PSU
I really think this person is toying with our good intention....Sometimes not all threads are real.....I detect a mischief maker here.....Just can't follow a simple instruction...then go and do something that makes no sense and ...voila...it comes ON....Sheeeeesh....Anyway budm....you certainly have the virtue of patience....I would have given up a long time ago.....just reading this post makes my head ache......Thanks.Comment
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Re: LG 42LW4500-LB Need help with repair of PSU
Is this guy for real. No offence . Mate you have been given some very clear instructions and only measuring low voltage instead you are opting to measure the higher more dangerous voltages. Personally I think you would be better off putting the cover back on and take it to someone who knows at least where the power switch is and how to do basic troubleshooting. Just because the power supply is on one board does not mean it automatically runs all the time. It requires other voltages and signals from other boards to allow all the different, voltage rails to turn on. Bud M has given you excellent advice. Measure the PS on voltage between ground and the ps on pin of power supply. If you don't feel confident just hook up Jumper clips to ground and a component off the ps on pin. Put your metre on dc not ac. Do you have a picture of your metre? Willing to help more but not if there is a risk of endangering your life. Even your electrotechnical teacher (as you put it) would dissuade you from touching it , unless of course this is some kind of joke , then you are just wasting people's time.Comment
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