Re: finlux 50fme242b-t flashing backlight leds
your problem could be with the four string driver IC (MP3394S), take the time to look at its data and how it works, as for the crispy black parts they were diodes that stop the strings back flowing, but should work without them as the LEDs will do the same job
flocko
Badcaps Legend
Last Activity: 06-17-2023, 08:29 AM
Joined: 11-08-2012
Location: dover
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Last edited by flocko; 07-30-2018, 08:35 AM. -
Re: finlux 50fme242b-t flashing backlight leds
There are two LEDs side by side in one case, if only one is working it will show as not being as bright, this is why using 4.5v to test them is useful as they do not burn your eyes out at this voltage, and you can see if only one half of the two are working (although they are working the shorted side will not lite ). If you have a lot of LEDs like these in any of the strings I would replace them as they will fail in timeLeave a comment:
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Re: finlux 50fme242b-t flashing backlight leds
alloy strip on rear of LEDs, heat until you can remove LEDs without force, replace by dropping the new LEDs on to the pads using a little flux, and heat from the rear ( make sure to have the LEDs the right way round) Good luck FlockoLeave a comment:
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HI Flocko's, please ca you take a look in my topic, than you.
[url]https://www.badcaps.net/forum/showthread.php?t=70693&page=4[/url]https://HI Flocko's, please ca you t...3&page=4[/url] -
Re: LG YSUS EBR73575201 - need schematic and repair kit.
Q709 is mounted on the heatsink others are SMD on the bottom of board,also check gate resistors to the aboveLeave a comment:
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Re: LG YSUS EBR73575201 - need schematic and repair kit.
Normal parts used for repair on these boards ( EAX 64286001 )are Q703/4/7/8+9 = RJP63K2 ,RJP30H2A and 20N60. details taken from my repair log book sorry no schematic hope this is of help FlockoLeave a comment:
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Re: Dixon 42" Plasma Model STY03423D (Bad picture)
faulty IPM on Y sus is my bet.Leave a comment:
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Re: Saving 60" 70" + Display Panels From Cracks...
(I posted this a long time ago, still works for me every time)I use a sheet of thick brown rapping paper (I have a roll 48" wide) , and slide this under the panel from the end without the tabs, then with a second pair of hands lift away like you would with a person on a blanket.the paper supports the screen and refitting it is just the reverse. I have with help used this for screen sizes up to 70" with no problems. I hope this is of help to you FlockoLeave a comment:
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Re: Digihome 32DLed906
Ron I am glad I have helped with your understanding and anyone else that come across this post. One other thing I must say about replacing LEDs is that do not use s/hand LEDs from old strips and try to resolder as the heat cycle that is needed to remove and refit will see it fail in a short time(heat kills LEDs)it is better to cut and stack the strip.Leave a comment:
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Re: Digihome 32DLed906
I am saying when you first come across a set with faulty LEDs that has a driver/power board shut down, then one or more shorted/open LEDs will be the problem(over/under current). So when replacing LEDs you must be mindful that they need to be of the same rating(size/ voltage/colour/and current consumed and allowed to pass)so you can see any LED that is under or over rated if you are replacing a large number will soon add up to be a problem, plus this being an older set that uses a power and stand alone driver board with only one LED string with 40 or more...Leave a comment:
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Re: Digihome 32DLed906
Sorry for"shot in the dark" pun, i thought it was funny , but let see if I can be more helpful, I dont think there is a problem with any of your boards (main /power and driver) but you will have if you try testing them the way you are. The driver board checks for over/under current, and if it see any will shut down, so stopping any risk of fire, so any change in LEDs (short/open) and the current they are drawing will shut the driver down, as you see a flash from the back lights we can tell that at least the driver is working, as is the main and power...Leave a comment:
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Re: LG EAY60968801 Power Supply Unit(Plasma 50pk series)
Yes I have to say this forum and youtube has had a hand in putting a lot of old time Tv repairmen out of a job.If you keep putting wood on the fire sooner or later you are going to run out of wood.so I see it as rough justice, if you get my drift FlockoLeave a comment:
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Re: Digihome 32DLed906
One dry joint on any of the replaced LEDs will see the driver shut down.And taking shots in the dark will not end up in a good place, putting 100+v though a strip that should run at about 25v. just as well the driver shuts its self down or you would need more new LEDsLeave a comment:
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Re: LG EAY60968801 Power Supply Unit(Plasma 50pk series)
Replacing caps would be my first call on any failing power supply, second to dry joints? thought you would have that covered after four weeks, your slipping TW this is schoolboy stuffLeave a comment:
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Re: Digihome 32DLed906
I told you in post 35 that your driver boards were shutting down and the reason why. your new LED tester will light the backlights as it does not work in the same way as the driver board,the fact that the leds flashed on when driven by the driver board shows it to be working, your problem is with the LEDs or the wiring to said strips Hope this is of helpLast edited by flocko; 11-04-2017, 04:57 AM.Leave a comment:
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Re: LG EAY60968801 Power Supply Unit(Plasma 50pk series)
ok back for a short time, we are going round and round here, and i am getting giddy,so lets start again. Power board jump auto ground to ground standby should read 3.5v, make RL_ON high, relay should come in,stby should now go to 5v ,17v, AC DET 4-5v,PFC (read at F302/801) 390v.make M_ON high to give VS/VA.at what point does the board fail?my thoughts were at the M_ON stage but you seem to be having a problem with the PFC ?Leave a comment:
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Re: LG EAY60968801 Power Supply Unit(Plasma 50pk series)
PFC can sub for 200v and 0.4 for th eother. Working 90-95V and PFC.Sorry you have lost me there? so where has the 390V PFC gone ? keep going you will get there but without me tonight , I am off to bed keep me updated good luckLeave a comment:
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Re: LG EAY60968801 Power Supply Unit(Plasma 50pk series)
keep tripping over each other glad to see your on the ball,I think you have changed PC901 that will also stop the controller bringing up VSLeave a comment:
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Re: LG EAY60968801 Power Supply Unit(Plasma 50pk series)
you need to use hot ground (neg leg of main cap)the two primary side tapping on the transformer are in series what are you seeing across the them( you may need to check and compare with the good board ).Leave a comment:
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Re: LG EAY60968801 Power Supply Unit(Plasma 50pk series)
Keep up, so to recap PFC good at 390v but no VS have you changed the L6599A control chip ,what are you seeing on the outputs of Q801/802 primary side of VS transformer ?Leave a comment:
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