Re: BN96-09744A Samsung TV Module, Y-Main board, LJ41-06153A, PN58B550T2FXZA
the jist of it is to look for components which dont work somewhat like they should.
nothing should have 0 ohms to ground (the trace where the screws attach). Probe around and see if you can something that does. Most likely it will be one of those components with a heatsink that shorts to ground.
then you have to look to see whats broken in that area that goes to ground. then it gets harder especially if you dont know electronics and it feels like you are just looking at random objects....
chico1st
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Last Activity: 12-19-2015, 12:31 PM
Joined: 01-11-2012
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Re: X-Main (LJ41-07015A) repair on my Samsung Plasma PN50B400P3D
Hmm fair,
I have no idea what the ERC is connected to since it seems to not connect to anything on the X main and thats the only circuit i looked through. A lot of the power seems to travel to the Y main. What does the ERC control? A general current to the plasma? Why would you need to H bridge it, can plasma go backwards?Leave a comment:
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Re: X-Main (LJ41-07015A) repair on my Samsung Plasma PN50B400P3D
OK the failure for this seemed to be a blown fet in the pull of the push pull driver which blew all the fets in the push pull and the driven impedance matching circuit (which goes to net ERC but I have no idea what that is).
In general i replace R4502 and R4102 with 15 ohm resistors since they were tied to Vcc in the failed condition and blew. Luckily the SO233 parts near it were fine.
I also replaced the four 360V push pull IGBTs with FGPF4536 since the originals were obsolete.
...Leave a comment:
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Re: X-Main (LJ41-07015A) repair on my Samsung Plasma PN50B400P3D
I successfully repaired this board. I wanted to change the title to be the PCB ASSY number instead of the PCB bare board number. Is there a way to update the title?
Then I will just dump my repair notes into this thread.Leave a comment:
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Re: X-Main (LJ41-07015A) repair on my Samsung Plasma PN50B400P3D
Also worth mentioning came to the conclusion that I was the X-main board by just plugging and unplugging the internal boards using the start up chimes as a sign that it was working.
the X buffer may be broken too...or whatever the 'HD' connector goes to but unplugging them and leaving x-main attached still resulted in no power and a clicking relay.Leave a comment:
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Re: X-Main (LJ41-07015A) repair on my Samsung Plasma PN50B400P3D
Yeah I have a multimeter and know how to use it.
I havent started pulling parts off yet.
Repairing parts in unknown schematics is new to me though. I assume I basically need to pull everything off to check them but I was hoping to know where to focus my efforts.
This is what i know so far:
-The chassis ground seems to be pretty much shorted to Vs (it has a bunch of 150uF 250V electolytic caps between it and chassis ground)
- The Vs rail also goes to the collector of some IGBT (RJP30E2DPP-M0)...Last edited by chico1st; 11-21-2015, 03:36 PM.Leave a comment:
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X-Main (LJ41-07015A) repair on my Samsung Plasma PN50B400P3D
Has anyone successfully repaired a X-Main (LJ41-07015A) from a Samsung Plasma PN50B400P3D.
I had no power on my TV and a clicking relay and I have narrowed it down to this board.
If anyone has repaired one before, has a schematic it would be useful or know general issues with 2009 ish Samsung Plasma TVs.
I attached an image of the board from shop Jimmy.... -
Re: Help fixing DAC-19M005 BF REV 01A
OK so I dont know if I'm making progress or not but now my backlight flashes along with my green LED indicator on the power switch. Probably about once a second and turns off, it makes a ticking sound just like before, but when the backlight is plugged in the noise is much louder.
All of the other SMD transistors measured well so I think I will go looking for the cause of that noise, I know the poster of that problem said they measured well but ill look for this odd ticking noise first. I have a high speed scope I can use to try...Leave a comment:
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Re: Help fixing DAC-19M005 BF REV 01A
No luck.
I tested the mosfets in and out of circuit and they were fine, i followed the posted method, but just so everyone knows when doing these tests it is easy to charge the FET and thus read a shorted output between drain and source, until you discharge it by shorting drain and source. (like in [URL="http://www.4qdtec.com/mostest.html"]this[/URL] test)
I plunked the 4A fuse (F1459CT-ND) in and it blew when I turned on the monitor.
I suppose Ill look into those Q-Transistors next.
...Last edited by chico1st; 01-19-2012, 01:14 PM.Leave a comment:
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Re: Help fixing DAC-19M005 BF REV 01A
ah i am following the advice, the 4A fuse is coming tomorrow from digikey and i plan to do the suggested mosfet test tomorrow before put I put the fuse in.
I just wanted to know what I could probe once the fuse is back in. I thought it would be a simple test to check if it was working before i plugged it to the ccfl.Leave a comment:
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Re: Help fixing DAC-19M005 BF REV 01A
Is there some point that I can probe to know if the backlight should work?
Possibly one of the voltages on CN200-CN203Leave a comment:
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Re: Help fixing DAC-19M005 BF REV 01A
The person (selldoor) who responded said that the 2Amp should work and I ought to fix whatever is causing it to blow.
this made sense to me to try to find the cause but would you guys recommend to just try the 4A fuse?
You hate cross posting, ok I can stop, based on the fact that the 2A fuse should work I didn't know what was the cause of my failures.
Most other forums i wander around in want people to separate threads whenever possible to not create super long threads, but point taken I should keep them all under...Last edited by chico1st; 01-17-2012, 09:56 PM.Leave a comment:
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Re: Help fixing DAC-19M005 BF REV 01A
Awesome, Im just starting to learn about fixing electronics
Yup, there are 3 surface mount fuses and 1 through hole (F102), only F200 is blowing though which seems to power most of the 2nd 1/2 of the circuit.
For the secondary transformer, I measure 0.7Kohm across the end pins (1-8 and 4-5) like you asked me to measure, this seems very high.
And just for fun i measured across the transformer, its open between the two ends (1-4 and 5-8).
2-7 and 3-6 are very low ~0.2ohm or something
On the...Last edited by chico1st; 01-17-2012, 12:26 PM.Leave a comment:
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Re: Help fixing DAC-19M005 BF REV 01A
I posted this because so far I haven't found any threads which helped me, at the moment I am mostly curious if those voltage levels are acceptable, and if that noise means anything to anyone (the 1 second repetition makes it seem special to me).
I know electronics fairly well as a note.
And i forgot to mention i used Panasonic FC/FM for replacements
and i retract what I said about measuring 170VDC after the diode bridge, that makes perfect sense.
Pictures attached...Last edited by chico1st; 01-17-2012, 08:51 AM.Leave a comment:
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Help fixing DAC-19M005 BF REV 01A
Hi there I have spent some time trying to fix my DAC-19M005 BF REV 01A in my AL1916W monitor.
[URL="http://www.google.ca/url?sa=t&rct=j&q=dac19m005%20schematic&source=web&cd=7&ved=0CFoQFjAG&url=http%3A%2F%2Ffxeurofanclub.ru%2Fload%2F0-0-0-13-20&ei=THsUT5auI8qR0QG5o9GwAw&usg=AFQjCNFx7xANnsZ-2T0T2Lc8d5lhj8hdAQ&cad=rja"]Schematic location[/URL]
I recapped all the electrolytics other than the large 400V (CE106) even the small guys (CE108 and CE107)
The FETs aren't shorted
My fuse blew and then reblew... -
Re: Fixing DAC 19M005, what fuse value?
It was "W" or "M"
Also i assume i should be ordering fast blow fuses, as opposed to standard or time delay.Leave a comment:
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Fixing DAC 19M005, what fuse value?
I am trying to fix my DAC 19M005 BF REV 01A and I was wondering what the F200 fuse value is.
In the schematic ([URL="http://www.google.ca/url?sa=t&rct=j&q=DAC+19M005+schematic&source=web&cd=7&ved=0CFoQFjAG&url=http%3A%2F%2Ffxeurofanclub.ru%2Fload%2F0-0-0-13-20&ei=KhsUT5XAGIfV0QGfsr3DAw&usg=AFQjCNFx7xANnsZ-2T0T2Lc8d5lhj8hdAQ"]here[/URL]) it states that the fuse is a 4A for the 00A REV whereas on [URL="http://www.ebay.ca/itm/DAC-19M005-Repair-Kit-L1975NW-L2046NV-AL1916-FPD-1830-/220499424191"]this[/URL] ebay kit it states that the...Last edited by chico1st; 01-16-2012, 07:44 AM. -
Do you get schematics?
When you guys are fixing TVs, monitors, PSUs etc do you get schematics for them?
Some troubleshooting just seems to be impossible without them.
If you are fixing a TV and don't have the schematics do you just check all the FETs, fuses and caps? since you don't know what any voltage levels should be or do you dissect the design from the PCB? -
Re: What current rating for a cap?
OK I understand the ripple current etc measurements at a high level, but on this data sheet for capxon KF...
the ripple current is measured in SV? what the heck is that?
I would assume that it reads as 10V 2200uF cap is 1.65 A ripple? is that right?Leave a comment:
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What current rating for a cap?
Hi there when I am selecting a current rating on a replacement cap how do I determine the current rating?
So far for any fixes I just choose the highest value that fits but how do you go about deciding if they are high enough?
Same goes for fuses.
Without having a schematic some of these things are hard.
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