Re: LG 42LW4500-LB Need help with repair of PSU
That is MOV and it is NOT BAD, if it is activated the main fuse would have blown, it is for surge protection and it is not needed for the TV to function.
You should be able to read 230VAC between the two legs of that MOV because it is basically connected in parallel with that grey line filter cap which are connected between Line and Neutral.
You are looking at the wrong section.
There is NOTHING WRONG with that MOV!
http://www.mouser.com/ProductDetail/...IfAz8bpg%3D%3D
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Re: LG 42LW4500-LB Need help with repair of PSU
I do not understand which part is bad TH501, TH101?Leave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
the red marked oneAttached FilesLeave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
All fuses are Okey main AC fuse is before this little b*tch
I want to know what is it and what i can replace it iam agry of it as I sed I had no voltage after the part I will mark it on anotherpost I cant get no voltage on the relay so relay cant switch the voltage to diodes when you press power button it will imidietly turn off TV so i cant turn it on 
i think the marked part is definetly bad please tell me what it is and what can i replace with it :/
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Re: LG 42LW4500-LB Need help with repair of PSU
How do you know the power supply is faulty? I would test the fuses first to see if theyre ok.Leave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
That is MOV VA101 and it does not look like it is damaged, if it has been activated it would have blown the main AC fuse.
NTC TH501 is for the inrush current limiter for the STANDBY power supply section.
NTC TH101 is for the inrush current limiter for the MAIN power supply section.Last edited by budm; 11-28-2016, 01:59 PM.Leave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
OK, so far you do have standby Voltage otherwise based on Post #1 "Hi guys today my TV stops working (it woudnt turn on only led shine so the power goes into it)"
Looking the board layout, you will not have any DCV between the two legs on any of the filter caps C612~C614 until you have > 2VDC at the 'PWR-ON' pin of the connector P201 to turn on the power relay RL101 to supply the 230VAC to the bridge rectifier BD101.
So check and see if you have DCV at 'PWR-ON' pin or not when the power switch is activated.Leave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
The black thing right to geay capacitor on main is what because it got damaged and no fuse after this part
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Re: LG 42LW4500-LB Need help with repair of PSU
BTW, I cannot read the PCBA P/N as printed on the barcode sticker to look for more info about the board.Leave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
We need clear straight shot pictures of the whole board.
There is a bridge rectifier (4-pin black device) mounted on the heatsink, you need to check the ACV between the two inner legs, it should have 230VAC between those two legs.
https://www.badcaps.net/forum/attach...8&d=1479570017Leave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
Yes 250VAC on gray cap on right side of it its some type of varistor or part (i dont know what it is and which one i need to replace) this part has voltage on + but if you try + and - no voltage everything after that it has no or bad voltage in miliamperesLeave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
https://www.badcaps.net/forum/attach...7&d=1479570017
So the fuse to left of the line filter cap (grey cap) is good for sure?
Are you getting 230VAC between the two legs of that grey cap?Leave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
Okey guys So I make big progresws today I check the big capacitors and no voltage on them the voltage stops on part INR or LNR next to main gray CAP so this part is definitly damaged does anyone know which one i need to replace ? it looks like Varistor but i dont know nothing about it
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Re: LG 42LW4500-LB Need help with repair of PSU
To start off, what is the DC voltage across those capacitors. See post #11Leave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
I will wait 2 days and try to find the problem with my teacher of electrotechnicsLeave a comment:
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Re: LG 42LW4500-LB Need help with repair of PSU
Ah okey thanks I wil try check it with my teacher but also i found something this board has 2 circuit primary and secondary and i cant measure ohms on resistors on second circuit thats weird on first sector of board theres no problem with measure ohms on resistorLeave a comment:
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The motherboard does not POST and has the following symptoms:
When the power button is pressed, the fans and RGB turns on.
When the power button is pressed, the motherboard voltages 12, 5, and 3 are connected.
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None of the diagnostic LEDs light up.
USB voltage is off.
VCORE voltage is off.
The BIOS software was downloaded from Asus site and installed using the Q FLASH button, but it made no difference.
I would appreciate it if anyone could guide me on the cause of the problem.
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