This article was prompted by a customer email just received a few minutes ago.
Originally I was about to send the response directly, but then decided to post the answer here as I kind of drifted away from the simple answer I could have given.
Which was in turn prompted by another customer exchange earlier today when I was told, and I quote here, 'You are damn right I was using abusive language...' because supposedly we've promised we would fix his TV and $200 later we still haven't. (which we haven't promised, of course, nor has he spent $200 on us, but that's another story).
It is not unusual to be on both sides of the fense on any given day.
Our business is based on problems, people come to us when they have problems and it is only natural that when we can't fix their problems that only presents them with bigger problems and tend to get the heat.
Which would explain why most TV technicians I've seen - and a good deal of our customers are actually TV technicians - are usually grumpy or snappy at best.
More on that in a bit, here is the email that prompted this article:
"Dear Coppell TV Repair,
sending a bad 6871QYH053B for repair. the board does not display picture.
It made a popping noise as soon as it was turned on the first time, tv will not power on when this board is connected(indicator light stay red).
The fuse furthest from the ic keeps blowing. the board is untouched. It was supposedly "brand new" when I bought it."
The 6871QYH053B is apparently blown and the IC on it is in need of replacement, nothing new here. Done that hundreds of times already and readers can find related articles here, here, here and probably in a bunch of other articles already.
What I wanted to focus on was the last sentence about the board being supposedly "brand new".
If anyone believes that in 2013, with a class action lawsuit against LG from several years ago and hundreds - if not thousands - of already sold repair kits for these boards - there are still any brand new boards out there then they have to give up whatever they are doing and join if not government's public relation head management then at least Microsoft's developer evangelists, who are probably still busy telling everyone how novel the next Windows Mobile version will be.
It is equally upsetting to see people who can be so naive and sellers that can be so either naive or stupid or evil to make such claims.
Maybe, just maybe LG or another big name may have a brand new board. If they indeed do it'll surely cost around and above the cost of a new TV the same size.
At least that's how it was the last time I checked and it makes sense to be that way, so it hardly would have changed.
I can't decide for myself how many of the sellers out there are lying on purpose and how many are lying just because they do not know any better.
I am leaning towards the majority being in the second group and in all fairness I am not a stranger to periodically finding myself in that group too.
Yet I think an intelligent person would realize the pattern over time and stop making claims that - at the least - they could not have verified.
But - here's a bummer - most TV technicians - and most chop shop retailers - are not intelligent.
You can't stay intelligent for long if all you do is deal with problems and grumpy customers or if you dismantle boards half the day and list them for sale the other half.
There's nothing to stimulate your brain in either of those activities (and I know that first hand too).
Oddly enough, I think the same also applies to modern doctors.
In general, I think TV repairmen are a lot like doctors - from having to deal with problems to tending to fall in the same pattern of resolving a common problem ("Temperature? Ok, it's the flu, you're the 10th since yesterday, and past 9 had the flu, so you must have it too") to developing the habit of NOT listening to what people want to tell them ("so here is what I did: I pressed the button and at first nothing happened, but then it came up as it normally does, only slower, and then it worked for like, what, 3-4 hours and then BOOOM - out of nowhere, just like that, it stopped working , but here's the thing...(me: z-z-z-z-z)".
I've got my fair share of dealing with doctors - just enough, thank you very much! - and here's what I'd say to those in the market for TV repairs and/or parts:
Finding a good TV technician is about just as hard as finding a good doctor, only luckily a whole lot less risky.
Like good doctors, good technicians aren't many even though there are plenty of technicians out there (or part outlets, for that matter).
Like good doctors good technicians are always busy, you'll have trouble getting to them and when you do they may sound a bit off and easily a bit rude to you. It's not because they are rude people, it's because they have a protection wall against the ever-growing waves of ever-needing people around them.
But, I'll repeat, they can easily come accross as rude if you're sensitive.
They focus on the problem, not the patient.
Good technicians tend to talk to themselves and often to the TV or module they're working on, just like I've seen a good doctor talk to the retina of my eyes.
Good technicians will not be cheap, but they definitely won't be the most expensive ones either.
They won't be cheap because they know the real value of what they do and they're not the kid next door trying to do what they do and enter the market without knowing the expenses they'll come accross as the practice grows.
You may find a good doctor/technician at the lowest price out there, but it's like shooting for a girl that's both pretty and smart and likes you. Oh well, you get the idea.
Prices won't be the highest, though, although I am not so sure this applies equally to doctors and TV technicians. A good technician/doctor is good because they do what they do because they have a talent for it and for them it looks easier than it actually is; they are aware of what it tends to cost on the market and they're glad to get well paid, but they also feel they couldn't be overcharging for something so easy.
Not sure how universal that is, but I think it's pretty universal.
Wednesday, March 13, 2013
Tuesday, February 5, 2013
From the mailbox - I am not making these up!
Below are some quotes from our correspondences with customers.
No offense meant, but I can't help but point out that a stronger dose of attention to detail is strongly recommended when trying to repair a device known to raise input voltage of 110AC.
Question:
What are symptoms of y sus board in my tv? (TV is HP PL5060N)
Answer:
Symptomatic for the YSUS board in HP PL5060N are the two large near square aluminum heat sinks sitting in a vertical line (one above the other) next to a smaller heat sink with 5 components on it; another symptomatic behavior of the YSUS is its tendency to display itself to the naked eye on the left side of the TV in days when the back TV cover is off its place.
If you have those symptoms you almost certainly have a case of a YSUS in your TV.
Question 2:
My light is on stays red when you push it and nothing.
Answer 2:
Still thinking how to respond to that one.
Answer 1:
Question 1: (a statement actually)
Was it
or
C) something else
Kindly expecting your response ASAP.
Question 2:
And yes, your claims are incorrect.
First this is not a scam or if it is then nearly 5000 people missed on it and reported happy outcome of their experience. That is too much for a public scam.
Question:
Yesterday I checked for 24v on the power supply board, between pins 1 of connectors 1304 and 1309. What do you think? Is that a sign the board needs repair?
- Fred
Answer:
No, the fact that you checked for 24V on the power supply board, between pins 1 of connector 1304 and 1309 is not a sign that the board needs repair.
No offense meant, but I can't help but point out that a stronger dose of attention to detail is strongly recommended when trying to repair a device known to raise input voltage of 110AC.
Question:
What are symptoms of y sus board in my tv? (TV is HP PL5060N)
Answer:
Symptomatic for the YSUS board in HP PL5060N are the two large near square aluminum heat sinks sitting in a vertical line (one above the other) next to a smaller heat sink with 5 components on it; another symptomatic behavior of the YSUS is its tendency to display itself to the naked eye on the left side of the TV in days when the back TV cover is off its place.
If you have those symptoms you almost certainly have a case of a YSUS in your TV.
Question 2:
My light is on stays red when you push it and nothing.
Answer 2:
Still thinking how to respond to that one.
Question 1:
Recibi un sobre con un numero de ratreo y una nota dentro pero no
dice cuando recibire mi articulo solo dice que si quiero cancelar llame o envie
un correo Quiero respuesta lo ante posible
Answer 1:
I am sorry, I do not speak Spanish.
Question 2:
Fuck you then, you must speak Spanish!
Question 1: (a statement actually)
i am canceling my order and i will be going to my bank tomorrow to
stop payment because i was led to believe i was buying a board no buying a box
to send in my board
Answer 1:
Sorry to hear about your experience.
Would you please kindly let us know who or what let you believe
that you were buying a board and NOT a repair service (and most certainly not a
box of any kind to send yours or any other board)?
Was it
a) the title, stating
"MAGNAVOX 42MF237S/37 / PHILIPS 42PFP5332D/37 POWER BOARD ***
REPAIR SERVICE ***"
or
b) The first paragraph in the listing stating
b) The first paragraph in the listing stating
"Coppell TV Repair offers a REPAIR SERVICE for the power board
shown on the picture below and used in certain Phlips/Magnavox 42'' plasma
TVs.
REPAIR SERVICE means that you have to send us your malfunctioning
board that we will attempt to service, test and return to you."
or
C) something else
Kindly expecting your response ASAP.
Question 2:
I viewed a board on ebay and there was a cost for the board nothing
stating a return board for repair and my message from Ebay and Pay Pal was my
board had been shipped. not that a box had been shipped. this is fraud and I
will persude action on my end to stop my payment .
Answer 2:
If you were being scammed hardly anyone would have bothered
responding to you in polite and factual manner.
Perhaps opening the listing and reading it would get you on a
better track.
Why don't you try it as opposed to throwing incorrect claims at
us?
And yes, your claims are incorrect.
First this is not a scam or if it is then nearly 5000 people missed on it and reported happy outcome of their experience. That is too much for a public scam.
Second, you may have viewed "a board" on eBay, but you have clearly
not reviewed the listing. Because the quotes in the previous post come right
from it and they are NOT in fine print. On the contrary, they are in bold, red
letters at the very top of the listing.
Right under "SERVICE DESCRIPTION - PLEASE READ IN FULL!"
All our repair service listings start in that fashion - something,
which is easy to verify.
Third, you will not be able to show me any place in the listing
which shows "cost for the board" as in your claim. I dare you!
You probably have a message from PayPal that your item was shipped,
correct. And that message is incorrect, which is explained in the shipping
instructions sent to on Sun 2/3/2013 11:55 PM - just
after the order was made and just as promised in the listing. All purchases for
repair services receive shipping instructions and yours was not any
different.
And then, because many absent-minded people place orders without
never actually reading what they are buying - even if it is written in the title
or the picture - we also send a follow-up snail mail reminder.
THAT is what was shipped to you. Not a board, not a package either.
A reminder to send us the board you want serviced or, at the very least,
something to bring your attention to the listing contents.
So now, would you please PLEASE open the listing and actually READ
it?
Regardless of whether you want to use it or not - either is fine
with us - would you PLEASE do what you were supposed to do in the very
beginning?
Question:
Yesterday I checked for 24v on the power supply board, between pins 1 of connectors 1304 and 1309. What do you think? Is that a sign the board needs repair?
- Fred
Answer:
No, the fact that you checked for 24V on the power supply board, between pins 1 of connector 1304 and 1309 is not a sign that the board needs repair.
Thursday, January 24, 2013
USPS shipping delays and wait-instead-of-ship-second policy
We frequently have emails from impatient users who haven't received their delivery by the expected date.
Usually it goes like this (actual quote):
"As of this date, 1/23/13, the below referenced shipment has not been received. It was ordered on 1/8/13 and shipped on 1/9/13. The USPS site has not updated shipping since 1/9/13 and today is two weeks.
Can I please get a replacement shipping? If I should receive the initital package, I will advise and promplty return. Thank you."
This is actually quite polite as far as request goes.
We may add a few more here when they arrive today or tomorrow.
When we receive a request like that we usually check the online tracking information and find out that the package is still "in progress", so we get back to the aggrivated aggravated buyer and make them even more aggravated by telling them that we've shipped on time (as can be seen) and that delivery is out of our hands.
To which they usually respond that this is not their problem, that they have customers (or TVs) waiting and that should we only ship another package they'll promptly return the duplicate when it arrives.
Most commonly the package just "disappears" somewhere during transit and goes MIA for days before it shows up.
Like in this case:
Sometimes the tracking information doesn't even show the package as picked up by the carrier, often until the day it arrives at destination at which point it shows all in one day and one place.
This is fairly common for USPS, but we haven't seen it with UPS so when a customer cried wolf around Christmas and UPS did not indeed show the package as picked up we first called them and then, because custome kept crying we sent another package.
Of $140 value.
But how could you leave someone without a TV at Christmas and New Year , especially when carrier information shows package was never picked up.
Must be still somewhere in your warehouse , right?
Wrong.
Package showed up two weeks later, just as the second one we sent (which also was not "picked up" until after Christmas - apparently a UPS mishap around holidays).
Think the customer returned the extra power board?
Wrong again!
When I have enough time I'll find the tracking numbers and the communication with that customer and post them as well.
For now, though, if you read those you should know why we wouldn't rush a second package when the first one is delayed somewhere in transit.
Usually it goes like this (actual quote):
"As of this date, 1/23/13, the below referenced shipment has not been received. It was ordered on 1/8/13 and shipped on 1/9/13. The USPS site has not updated shipping since 1/9/13 and today is two weeks.
Can I please get a replacement shipping? If I should receive the initital package, I will advise and promplty return. Thank you."
This is actually quite polite as far as request goes.
We may add a few more here when they arrive today or tomorrow.
When we receive a request like that we usually check the online tracking information and find out that the package is still "in progress", so we get back to the aggrivated aggravated buyer and make them even more aggravated by telling them that we've shipped on time (as can be seen) and that delivery is out of our hands.
To which they usually respond that this is not their problem, that they have customers (or TVs) waiting and that should we only ship another package they'll promptly return the duplicate when it arrives.
Most commonly the package just "disappears" somewhere during transit and goes MIA for days before it shows up.
Like in this case:
This is fairly common for USPS, but we haven't seen it with UPS so when a customer cried wolf around Christmas and UPS did not indeed show the package as picked up we first called them and then, because custome kept crying we sent another package.
Of $140 value.
But how could you leave someone without a TV at Christmas and New Year , especially when carrier information shows package was never picked up.
Must be still somewhere in your warehouse , right?
Wrong.
Package showed up two weeks later, just as the second one we sent (which also was not "picked up" until after Christmas - apparently a UPS mishap around holidays).
Think the customer returned the extra power board?
Wrong again!
When I have enough time I'll find the tracking numbers and the communication with that customer and post them as well.
For now, though, if you read those you should know why we wouldn't rush a second package when the first one is delayed somewhere in transit.
Wednesday, January 9, 2013
Repairing a trashed Philips 42MF231D/37 - what you must know
Question:
I have a Magnavox 42MF231D/17 found in trash. blue light turns on on front of TV, relays click, no picture.
It sounds like there is a power line-like buzz coming from the Y-SUS board. I haven't really been able to find any tips on diagnostics. This is my first Plasma TV repair.
I have found the model of the Y-Sus board and Buffers on ebay for about $200. That sounds like a fair bit of money for something i found on the side of the road!
I am interested in fixing the TV.
Answer:
The Magnavox 42MF231D/17 plasma TV uses the infamous trio LJ92-01200A and the accompanying two buffer boards that are subject to past articles in this forum and (subsequently) many other places around the web.
The trio is the most likely culprit in the TV, but I would start with focusing your attention to the fact that while easily the most likely candidate you should not automatically take it for granted that this is the problem in your particular case. it may as well be power board or main board, may be the ZSUS or practically anything else, not that much else is left.
But since the Y-Main and the buffers are far above any other board in the suspect list it is practically justified looking there first once you know it's not an essential failure in the power board, i.e. the TV is not completely dead, for example.
I would also point your attention to the following: eBay and the Net in general is by now full with bad replacement sets, usually from China, but also local. ShopJimmy also offers used sets when they have them and in my opinion this is just as bad as the Chinese sets only it can get to you faster.
By "bad replacement sets" I mean sets that are made up of one original or repaired Y-Main board and two original (or, less often, repaired) buffer boards of the original release with 6 ICs. Those are time bombs waiting to explode on you and it won't be long before they do.
For more details see
http://blog.coppelltvrepair.com/2012/03/ebay-fraud-samsung-brand-new-upper-and.html
and the longer and more detailed
http://blog.coppelltvrepair.com/2010/10/lj92-01200a-lj41-02759a-truth-according.html
Bottom line recommendation is this:
First, make sure you get both the Y-Main LJ92-01200A and the two buffer boards from the same source; this will make it easier for you to handle any issues with them whereas if you get sustain board (repaired or replaced) at one source and the buffers from another, should a problem occur they'll both blame each other and you'll be in the middle cursing everyone including yourself.
Second, always go for new buffers with 4 ICs hopefully from a reliable source; it's been enough time since they were produced at the end of 2010 and by 2013 there are still brand new ones available through reliable Samsung vendors, but they cost a bit more (Samsung keeps prices high and only works with limited set of distributors resulting in longer and more expensive distribution chain) and there are most likely already used buffers with 4 ICs which may also have limited life left in them.
Third, you don't always need to service the Y-Main board when a buffer fails. Read the above articles and if you have an image with horizontal lines only then your Y-Main is still good and you only need buffer boards.
And even if the display is all dark you may still have a good Y-Main and bad buffers, only this is less likely.
Send all three to a reputable repair company (like us) and if you don't need to repair the Y-Main it'll be a bit cheaper.
Point here is to send boards for evaluation and repair rather than buying a full set outright since in this case you pay as if your Y-Main is bad (which it indeed will be most of the time) while if you can stay a few more days without that TV it is worth sending the boards for evaluation and possibly paying less.
Four and last, we do both repairs and exchanges of complete sets, we are smart, reliable, professional, intelligent, honest and , above all, modest. So no reason to go anywhere else, right?
Send your trio for repair or buy a a replacement set outright.
Or we will tell the teacher!
I have a Magnavox 42MF231D/17 found in trash. blue light turns on on front of TV, relays click, no picture.
It sounds like there is a power line-like buzz coming from the Y-SUS board. I haven't really been able to find any tips on diagnostics. This is my first Plasma TV repair.
I have found the model of the Y-Sus board and Buffers on ebay for about $200. That sounds like a fair bit of money for something i found on the side of the road!
I am interested in fixing the TV.
Answer:
The Magnavox 42MF231D/17 plasma TV uses the infamous trio LJ92-01200A and the accompanying two buffer boards that are subject to past articles in this forum and (subsequently) many other places around the web.
The trio is the most likely culprit in the TV, but I would start with focusing your attention to the fact that while easily the most likely candidate you should not automatically take it for granted that this is the problem in your particular case. it may as well be power board or main board, may be the ZSUS or practically anything else, not that much else is left.
But since the Y-Main and the buffers are far above any other board in the suspect list it is practically justified looking there first once you know it's not an essential failure in the power board, i.e. the TV is not completely dead, for example.
I would also point your attention to the following: eBay and the Net in general is by now full with bad replacement sets, usually from China, but also local. ShopJimmy also offers used sets when they have them and in my opinion this is just as bad as the Chinese sets only it can get to you faster.
By "bad replacement sets" I mean sets that are made up of one original or repaired Y-Main board and two original (or, less often, repaired) buffer boards of the original release with 6 ICs. Those are time bombs waiting to explode on you and it won't be long before they do.
For more details see
http://blog.coppelltvrepair.com/2012/03/ebay-fraud-samsung-brand-new-upper-and.html
and the longer and more detailed
http://blog.coppelltvrepair.com/2010/10/lj92-01200a-lj41-02759a-truth-according.html
Bottom line recommendation is this:
First, make sure you get both the Y-Main LJ92-01200A and the two buffer boards from the same source; this will make it easier for you to handle any issues with them whereas if you get sustain board (repaired or replaced) at one source and the buffers from another, should a problem occur they'll both blame each other and you'll be in the middle cursing everyone including yourself.
Second, always go for new buffers with 4 ICs hopefully from a reliable source; it's been enough time since they were produced at the end of 2010 and by 2013 there are still brand new ones available through reliable Samsung vendors, but they cost a bit more (Samsung keeps prices high and only works with limited set of distributors resulting in longer and more expensive distribution chain) and there are most likely already used buffers with 4 ICs which may also have limited life left in them.
Third, you don't always need to service the Y-Main board when a buffer fails. Read the above articles and if you have an image with horizontal lines only then your Y-Main is still good and you only need buffer boards.
And even if the display is all dark you may still have a good Y-Main and bad buffers, only this is less likely.
Send all three to a reputable repair company (like us) and if you don't need to repair the Y-Main it'll be a bit cheaper.
Point here is to send boards for evaluation and repair rather than buying a full set outright since in this case you pay as if your Y-Main is bad (which it indeed will be most of the time) while if you can stay a few more days without that TV it is worth sending the boards for evaluation and possibly paying less.
Four and last, we do both repairs and exchanges of complete sets, we are smart, reliable, professional, intelligent, honest and , above all, modest. So no reason to go anywhere else, right?
Send your trio for repair or buy a a replacement set outright.
Or we will tell the teacher!
Wednesday, December 5, 2012
LV49152 digital audio amplifier for Sanyo DP46840
We recently had to work on a main board for Sanyo LCD TV from the DP series, specifically DP46840.
It had a hole burned in the audio amplifier IC LV49152 and we apparently had to replace it.
It turned out hard to find LV49152 here in the States, so if you find yourself in the same boat perhaps this will help:
http://www.coppelltvrepair.com/p/117/lv49152-sanyo-audio-power-amplifier-ic-lv49152v
I am quite certain LV49152 is also used in other main boards from Sanyo and likely other manufacturers.
Please note it is a bit tricky to solder the IC properly on a board. Pay special attention to providing good soldering contact of the exposed pad underneath the IC - cook it slowly and do not overdose soldering paste!
Hope this helps!
It had a hole burned in the audio amplifier IC LV49152 and we apparently had to replace it.
It turned out hard to find LV49152 here in the States, so if you find yourself in the same boat perhaps this will help:
http://www.coppelltvrepair.com/p/117/lv49152-sanyo-audio-power-amplifier-ic-lv49152v
I am quite certain LV49152 is also used in other main boards from Sanyo and likely other manufacturers.
Please note it is a bit tricky to solder the IC properly on a board. Pay special attention to providing good soldering contact of the exposed pad underneath the IC - cook it slowly and do not overdose soldering paste!
Hope this helps!
Thursday, November 15, 2012
Repair kit for 6871QYH039B LG YSUS sustain board
Question:
Our store is definitely a work in progress as of November 2012.
We apologize about that.
Here is the link for the 6871QYH039B repair kit...(currently only serving USA customers):
http://www.coppelltvrepair.com/p/99/6871qyh039b-ysus-board-repair-kit
Dear Ccoppell TV Repair,Answer:
Tom Wilcox
I have reviewed your online store and have not located this particular part, maybe I'm just overlooking it but I need your help Identifying it and/or your listing for it,please.
from LG50pc3d-ud plasma,, ysus board 6871qyh039b,, ipm 201 #yppd-jo16e-c and ipm 202, yppd-j015e-c.
016e has pin layout 7 on one side, the other 3,6,1 and 3
015e has pin layout 7 on one side, the other 6, 6, and 6
please send listing or correct replacement part number and pricing info.
thanks,Tom
P.S. I want to say thanks for the help I have gotten via your blogs! great job!
Our store is definitely a work in progress as of November 2012.
We apologize about that.
Here is the link for the 6871QYH039B repair kit...(currently only serving USA customers):
http://www.coppelltvrepair.com/p/99/6871qyh039b-ysus-board-repair-kit
Wednesday, November 14, 2012
Repairing 4H.V1448.481 backlight inverter board from Insignia-NS-LCD37-09
A year ago I posted an article about replacing the original inverter in Insignia NS-LCD37 LCD TV with 4H.V1448.481 since it was more available and cheaper.
Well since then the newly installed inverter has also failed - in fact twice - and the second time I opted to repair it as opposed to replace it since I already had a dud handy.
The same backlight inverter 4H.V1448.481 is used in a good number of other LCD TVs such as Philips 32PFL5322D/37, PROSCAN 37LB30QD, Sanyo DP37647 and in fact many more, so hopefully this will help others in same boat.
Failure symptoms were the same both times - display will lit up for a split second and will then turn black, the TV otherwise still operating properly.
Inspecting the inverter I found a blown SMD fuse - one of several along the length of the board - and that told me in which section the problem will be.
Here is how the fuse looks like:
As can be sen from the picture the fuse is 3A/32V and is driving two power transistors, each of which in turn drives a transformer on the board (well the last can not be actually seen on this picture; just take my word for it, ok?).
So there is one such fuse for every two power transistors / transformers and you will be looking for a fuse that is blown and does not have continuity.
Once I got the group, I first ruled out the power transistors by comparing them and finding out that they have the same resistance as all others.
The culprit turned out to be - not surprisingly actually - one of the two transformers although I could not figure which one until I put a more powerful fuse (5A as opposed to 3A) and tried to see what happens.
But I do not recommend you do that.
As it turned out, the bad transformer could very easily be distinguished once pulled out of its place and inspected on the back.
Here is what it looked like:

Clearly it was the primary winding that has burned and because it has low resistance I could not find the difference with a meter.
The board itself also had traces of burning:

Replacing the transformer with a pull-out from the first defective board restored full functionality....for now.
Hope this helps!
Well since then the newly installed inverter has also failed - in fact twice - and the second time I opted to repair it as opposed to replace it since I already had a dud handy.
The same backlight inverter 4H.V1448.481 is used in a good number of other LCD TVs such as Philips 32PFL5322D/37, PROSCAN 37LB30QD, Sanyo DP37647 and in fact many more, so hopefully this will help others in same boat.
Failure symptoms were the same both times - display will lit up for a split second and will then turn black, the TV otherwise still operating properly.
Inspecting the inverter I found a blown SMD fuse - one of several along the length of the board - and that told me in which section the problem will be.
Here is how the fuse looks like:
As can be sen from the picture the fuse is 3A/32V and is driving two power transistors, each of which in turn drives a transformer on the board (well the last can not be actually seen on this picture; just take my word for it, ok?).
So there is one such fuse for every two power transistors / transformers and you will be looking for a fuse that is blown and does not have continuity.
Once I got the group, I first ruled out the power transistors by comparing them and finding out that they have the same resistance as all others.
The culprit turned out to be - not surprisingly actually - one of the two transformers although I could not figure which one until I put a more powerful fuse (5A as opposed to 3A) and tried to see what happens.
But I do not recommend you do that.
As it turned out, the bad transformer could very easily be distinguished once pulled out of its place and inspected on the back.
Here is what it looked like:

Clearly it was the primary winding that has burned and because it has low resistance I could not find the difference with a meter.
The board itself also had traces of burning:

Replacing the transformer with a pull-out from the first defective board restored full functionality....for now.
Hope this helps!
Subscribe to:
Posts (Atom)

