Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
OK, I just trace out the board. Check D611 to see if it is shorted.
OK, I just trace out the board. Check D611 to see if it is shorted.
-
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: Sylvania lc320ss2 LCD TV keeps blowing fuse
OK, this is the best I can do due to the white paint masking on the bottom side, I cannot trace out the Gate drive, but this will give some idea what to look for on the board. You can see that it has many Zener Diode across the output of the power supply, they need to be checked.
Check Q601 and all the Diodes in the primary side, Q601 could have been damaged also when Q600 shorted out.Attached Filesif you find these attachements useful please consider making a small donation to the site
Last edited by budm; 01-19-2013, 01:58 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
-
-
Please upload pictures using attachment function when ask for help on the repair
http://www.badcaps.net/forum/showthread.php?t=39740Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
have you checked the inductors L600+L601 i have had shorts on other power boards with them?Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
Inductors are coils of wire. They are supposed to read short.Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
Not between the coils there not?Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
That's a lot of work @budm, thanks for taking the time.
Yeah I had previously checked d611 and it was alright.
Short of maybe 2 or three I think I checked all the other diodes on the primary side.
I'll try a few things now and report back.
@floco, I'll check the inductors with the blue ring tester to see if it picks it up.Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
Oh, yeah I had checked Q601 already, it's good.Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
Alright @budm to answer your question, I just did that test of removing the power fet and here is what happens. The lightbulb does not light up and I get 179vdc on the filter cap. The FET is still good too.
I'm now going to check a bunch of those zeners on the secondary side by the output lines.Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
So the mosfet you have removed - that is the one on the heatsink
-yes? Well as I asked before is it insulated from the heatsink?
was the original one insulated or in a plastic casing.Please upload pictures using attachment function when ask for help on the repair
http://www.badcaps.net/forum/showthread.php?t=39740Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
selldoor, sorry I didn't understand your question before.
No it was just screwed down onto the heatsink, the same way I have it now.Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
Ok but did you check if the original was in a plastic moulded casing and is the new one in a plastic casing. Sometimes a mosfet with almost the same part number comes in an insulated type and sometimes in a type that is connected electrically to the heatsink. If you get the second type instead of the first it will short.Please upload pictures using attachment function when ask for help on the repair
http://www.badcaps.net/forum/showthread.php?t=39740Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
Oh, good to know.
No they look identical both the original and the replacement when it comes to the packaging and no the original was mounted on the heat sink directly without any plastic casing.Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
Insulated:
Not insulated:
Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
Cool.
Yeah then It's the insulated packaging on both the original and the replacement FET
Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
Here is a picture highlighting the components I've tested today and also some from before. The ones enclosed in a orange square are those I'm not sure how to test therefore I opted for removing from the circuit (one at a time) and test to see if anything changed and it did not.
The ones enclosed in red are the ones i've tested and found to be good.
The two big inductors checked out ok with the blue ring tester.
From the bunch of diodes (orange/black) there were a few reading higher than the rest, around 700+ where most other ones would read around 500 just to point that out.
Would love to learn when and when not a component could be tested in-circuit. You know just a few things I could start learning like "you can check a given component in circuit as long as it doesn't have a certain component in parallel/series etc". I currently have an analog meter, a digital meter, a capwizard and a bluering tester.
Also was wondering if using a lesser watts lightbulb (currently using a 100W) could help in getting the shorted component be spotted out easier due to it getting hotter. At the moment the only components that get slightly warm are the large cement resistors and the rectifier diodes, if I remember right.Attached Filesif you find these attachements useful please consider making a small donation to the site
Comment
-
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
So is it still blowing fuses?
Sometimes the lightbulb trick doesn't work for these designs, due to the self-oscillating nature. It'll just stay lit as the circuit oscillates.
A lower power lightbulb would lead to less heat, not more.Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
"Would love to learn when and when not a component could be tested in-circuit."
Logging off now - I dont know if you have seen this guide written by retiredcaps, it contains lots of tests most are carried out without power to the boards.
https://www.badcaps.net/forum/showthread.php?t=10419
There are few updates the latest starts at post19.Please upload pictures using attachment function when ask for help on the repair
http://www.badcaps.net/forum/showthread.php?t=39740Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
I wouldn't dare try it without the lightbulb. Last time I did, I had to replace some of the new components again plus thefuse which it blew up horribly. Since it's very bright and I'm not getting the right voltage on the filter cap I'm thinking there's still something shorted. And of course this is while on stand by, and the tv wouldn't turn on so...Comment
-
Re: Sylvania lc320ss2 LCD TV keeps blowing fuse
With the lightbulb in place and a self-oscillator failing to start you'll see nothing across the primary cap.
Eventually you have to, unfortunately, risk it without the bulb, unless you have a variac to slowly ramp it up.Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.Comment
-
Good day folks......wow this new layout is weird. It's like I woke up one day and I'm no longer on Planet Earth or something
Anyway....got this here power brick from a USB to SATA adapter which keeps blowing the fuse after I almost repaired it. The reason I even bother to fix a power brick (wall wart, whatever) in the first place is because this thing was really convenient to use: I'd just plug it and that's it. It's a dual output supply, for both 12v and 5v, which although I COULD easily obtain with a DC-DC converter from a standard 12v adapter, I thought I should crack open the... -
Looking for some assistance please.
Trying to repair a PD27AOQ samsung power board.
Initially had the typical problem of cm806 capacitor blown, additionally thermistor NT801s blown.
Replaced the ceramic capacitor, str60252s, bridge rectifier, thermistor and fuse.
Testing it the fuse blows immediately power is turned on.
diodes dm852 and dm853 test as shorted when in the board but fine when removed.
any assistance, guidance would be appreciated. -
Hi all,
I am a newbie and not very experienced so bear with me if i struggle sometimes with technical language - but I'll do my best. I searched "Samsung" and the model number on the forum but didn't find anything I could understand!
I'm not an electronics guy - just picked up stuff over the years through my flight-simming hobby.
I have the above mentioned 46" tv as the monitor for my flight-sim setup. Recently it went "crack" and stopped working. No standdby light and no response. I assumed a fuse had blown and after investigation... -
Hello, I disassembled this dead camera, and found this WTF… Two fuses soldered one above the other !
I was pretty sure nobody touched it before, but that can't be from factory. There is flux, and capacitor is probably missing.
The other weird thing : the fuses are « G » fuse : (0.75A – 8V), seems very low. The original fuse should be « O » : (32V 2,5A).
There is « O » mark beside. All fuses have the same mark letter on main board. So, I can deduce it's a « O » fuse.
And this correspond to the issus I saw : when I plug the battery, I measure the voltage dropping... -
Hi all, so i was watching tv acreen went black and no sound. Traced problem to blown tcon fuse. Replaced and it blows replaced again samething. So my tcon fuse keeps blowing. I bought a new board havent installed yet infear its just going to keep blowing the fuse. If i only connect the right side ribbon cable the fuse doesnt blow but as soon as i connect the left cable my tcon fuse instantly blows and no picture. The right side picture works clear as day and left side picture is grey (picture attatched) im hoping its a bad tcon board itself or a cable or anything and not the panel. Thank you for...
Comment