Monitor will not turn on. Does it have a fuse I can change?

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I've a 22" Westinghouse LCD Monitor that stopped working from one day
to the next. The light the normally comes on when the monitor is on
doesn't even light up. Could it be that a fuse has blown on the
inside? Maybe one I could replace? Or perhaps the on/off switch
has gone bad. If anyone can provide a credible reason it stopped
working and a possible fix, I'd be most grateful.

BP
 
I've a 22" Westinghouse LCD Monitor that stopped working from one day
to the next. The light the normally comes on when the monitor is on
doesn't even light up. Could it be that a fuse has blown on the
inside? Maybe one I could replace? Or perhaps the on/off switch
has gone bad. If anyone can provide a credible reason it stopped
working and a possible fix, I'd be most grateful.

BP
Click to expand...
Could be a fuse, but could also be a ton of blown or bulged capacitors inside.
If you dare and are good with a soldering iron and a desoldering tool, go
ahead and open it up and look. I repaired a Acer 24" monitor that was 2 weeks
out of warranty. I had to replace 18 capacitors of differing ratings, but it
works like day one now.
 
I've a 22" Westinghouse LCD Monitor that stopped working from one day
to the next. The light the normally comes on when the monitor is on
doesn't even light up. Could it be that a fuse has blown on the
inside? Maybe one I could replace? Or perhaps the on/off switch
has gone bad. If anyone can provide a credible reason it stopped
working and a possible fix, I'd be most grateful.
Click to expand...

The Westinghouse LCM-22W2 manual doesn't provide any user service advice
in its troubleshooting for no power except to be sure that the monitor
AC cord is plugged in to the back and the wall and that the wall plug
has power.

Even with no vid signal, the power light is supposed to be orange, green
when operational

I don't think you can pay to troubleshoot it and replace something for
the price of replacement.
 
The Westinghouse LCM-22W2 manual doesn't provide any user service advice
in its troubleshooting for no power except to be sure that the monitor
AC cord is plugged in to the back and the wall and that the wall plug
has power.

Even with no vid signal, the power light is supposed to be orange, green
when operational

I don't think you can pay to troubleshoot it and replace something for
the price of replacement.
Click to expand...
Definately would cost more to pay someone else to fix than to just buy a new
24"-26" for around $200 or so. But like i said, if you know how to solder ,
a blown fuse , if its that, would cost all of a few dollars if that, and even
if every capacitor in the unit is needing replacement, it most likely wont
cost you more than $10-$15 for those parts.
 
Winniethepooh said:
if every capacitor in the unit is needing replacement, it most
likely wont cost you more than $10-$15 for those parts.
Click to expand...

But seriously. That is neither here nor there.
--
 
I've a 22" Westinghouse LCD Monitor that stopped working from one day
to the next. The light the normally comes on when the monitor is on
doesn't even light up. Could it be that a fuse has blown on the
inside? Maybe one I could replace? Or perhaps the on/off switch
has gone bad. If anyone can provide a credible reason it stopped
working and a possible fix, I'd be most grateful.

BP
Click to expand...

It helps if you have a model number to work with. The following
is just an example I made up for myself :-)

*******

I can't see a fuse here. Just a moderately dangerous open-face
assembly to work on (yellow PCB).

http://www.ccl-la.com/blog/index.php/repairing-the-westinghouse-lcm-22w3/

http://i.ebayimg.com/15/!Bud)9zgCGk~$(KGrHqQOKigEvN2wjNhrBM!eFK8N2Q~~_1.JPG?set_id=880000500F

I'm guessing, signal flow, left to right, bottom half, is
AC input filter, rectify to HV DC, switching transistor on heatsink
for HV primary side DC, transformer in yellow, with turns ratio to
fix output voltage, rectifiers on heatsink (synchronous rectification,
or just plain rectifiers ?), and a bunch of filter caps for low
output voltages. Eight pin connector carries low voltages
to the adapter board (adapts DVI and VGA, to panel signals,
does scaling perhaps).

The top section includes two HV inverters, taking perhaps 12VDC
in and giving 700-1000 VAC output at high frequency, to run the
backlights. I see perhaps two optoisolators (8 pin) ? And the
three yellow things on the right could be small transformers,
not really sure what that would be for.

Depending on the era, the capacitors could be leaking, and the
unit may have managed to detect an internal overload, shutting
down the switching action.

It could have a fuse, as I can't identify every component in the picture.
For example, there is a black blob below the three pin AC plug. The
PCB assembly is really cheap, and appears to be a single sided layout,
with wire straps used on the component side, to complete the layout.
Rather than put copper tracks on both sides of the PCB, they put
most of the copper tracks on the back. When a signal needs to
jump, they use those bare exposed straps on the component side.

The supply board is made by Delta Electronics. And that particular
example is DAC-19M009. The only thing I can see on Ebay, is someone
offering to accept your power supply board, and replace the
caps for you. Even though there could be other damage to the
thing. It isn't always going to be just the caps that
are damaged. When caps fail, sometimes other components
are damaged in collateral action.

Any sizzling, smoke, or funny smells before this happened ?

The thing is, even if there was a fuse, that fuse blew for a reason.
Just replacing the fuse won't fix it. The fuse would only blow again,
until you fixed it right.

It is possible for an engineer, to use a wrong value fuse, leading
to nuisance trips. But I haven't seen a mistake like that in
eons. Most of the time, the fuse will blow, to tell you there
is a serious problem elsewhere. A problem that must be fixed
first, before you can contemplate changing the fuse.

Paul
 
Paul said:
I can't see a fuse here. Just a moderately dangerous open-face
assembly to work on (yellow PCB).

http://www.ccl-la.com/blog/index.php/repairing-the-westinghouse-lcm-22w3/
Click to expand...

That's a useful description to help sell his package of capacitors.
It could have a fuse, as I can't identify every component in the picture.
Click to expand...
The thing is, even if there was a fuse, that fuse blew for a reason.
Just replacing the fuse won't fix it. The fuse would only blow again,
until you fixed it right.
Click to expand...

One of the comments had a fuse, the tech guy answered that there are two.

Comments 5 & 7 - the numbering system is imperfect w/ dupes

=========

# Peter Triffitt on Wed, 17th Mar 2010 4:03 pm

Hello Sirs.
What a brilliant site!! My monitor has just stopped working, no
noticable warnings.I have the board DAC-19M009 on my bench, and it all
looks in order. But I have tested the fuse (F101) and it is open
circuit, there is also a very slight area of soot between the fuse
connections. Shall I replace the capacitors anyway? Can you supply the
fuse? Or is this a different fault?
Best Regards Pete.

# CCL_TECH on Sun, 21st Mar 2010 3:55 pm

Yes, We can provide the fuse. Which fuse is blown, the one on the ac
side or the pico fuse on the bottom of the board?

=========

Further down there is more description about that fuse.
 
Mike said:
That's a useful description to help sell his package of capacitors.



One of the comments had a fuse, the tech guy answered that there are two.

Comments 5 & 7 - the numbering system is imperfect w/ dupes

=========

# Peter Triffitt on Wed, 17th Mar 2010 4:03 pm

Hello Sirs.
What a brilliant site!! My monitor has just stopped working, no
noticable warnings.I have the board DAC-19M009 on my bench, and it all
looks in order. But I have tested the fuse (F101) and it is open
circuit, there is also a very slight area of soot between the fuse
connections. Shall I replace the capacitors anyway? Can you supply the
fuse? Or is this a different fault?
Best Regards Pete.

# CCL_TECH on Sun, 21st Mar 2010 3:55 pm

Yes, We can provide the fuse. Which fuse is blown, the one on the ac
side or the pico fuse on the bottom of the board?

=========

Further down there is more description about that fuse.
Click to expand...

I didn't even notice the comments section :-)

I see one comment in there:

"I ordered a replacement fuse, and replaced the bridge rectifier too,
but it popped right away again. Does that mean I should do the
capacitor kit now?"

That is what I'm talking about. The fuse isn't the cause of the problem,
it is a symptom. It tells you something else is cooked.

I also liked the description, where a poster said their transformer
was running hot. So who knows what other things can fail on that
power board.

The thing labeled as a picofuse, could be a polyfuse. But because the
picture is out of focus, it's really hard to say what it is. My
experience with picofuses, is they blow easily, and my buddies used
to multiply the rating a fair bit, to keep them going. (I.e. Use a
10 amp pico in a 2 amp circuit.) And even then, they weren't super
reliable. So we used picos on lab prototypes, to prevent stuff
from burning up - if one popped, it didn't take long to fit another
one. But sprinkling them in a production circuit would be another
matter. Fuses are bad in any case, and generally, they're installed
when you need some kind of certification. It you were to put them
into a circuit "because you were nervous", the warranty claims
coming from the field, would be never ending. The boss would probably
make you solder in all the warranty replacements, as punishment.

Paul
 
Neither one of those scenarios seems likely.

Are you certain it's the monitor that has gone bad? In the several
dozen situations where I've helped someone with a monitor that keeps
shutting off, the vast majority have been because the attached computer
is not providing a signal.

Is there any way you can swap monitors with a different PC long enough
to see which part is the culprit?
Click to expand...

I have seen a large number of monitors fail by perpetually going into
standby. There's no question it's the monitor as the monitor will
fail no matter what PC and a different monitor will work on the PC.
 
[email protected] said:
I've a 22" Westinghouse LCD Monitor that stopped working from one day
to the next. The light that normally comes on when the monitor is on
doesn't even light up. Could it be that a fuse has blown on the
inside? Maybe one I could replace? Or perhaps the on/off switch
has gone bad.
Click to expand...

Fuses usually don't blow unless something has gone bad, like a power
transistor or chip that's shorted, and often those short out because
electrolytic capacitors go bad, as others have suggested. BadCaps.net
has several forums about electronics repair, including one about
monitors. Also check YouTube videos
 
I've a 22" Westinghouse LCD Monitor that stopped working from one day
to the next. The light the normally comes on when the monitor is on
doesn't even light up. Could it be that a fuse has blown on the
inside? Maybe one I could replace? Or perhaps the on/off switch
has gone bad. If anyone can provide a credible reason it stopped
working and a possible fix, I'd be most grateful.

BP
Click to expand...

Okay, back to the basics. Did you actually check the power cord was
plug in (to BOTH the monitor and into a wall socket or power strip)?
Have you tried wiggling both ends of the power cord to check if it is
fully inserted or has intermittent connections? If not plugged into a
wall socket and instead into a power strip, UPS, or something else, did
you unplug the cord and try a wall socket? Did you plug something ELSE
known to work into that same wall socket, like a lamp with a good bulb?
 
Fuses usually don't blow unless something has gone bad, like a power
transistor or chip that's shorted, and often those short out because
electrolytic capacitors go bad, as others have suggested. BadCaps.net
has several forums about electronics repair, including one about
monitors. Also check YouTube videos
Click to expand...

Some fuses do indeed blow just from old age.

I've recovered 'dead' Trinitron monitors from the NYC sidewalk just by replacing
the failed slow-blow fuse in the input line. After 18 months one's still
working great, the other is in reserve waiting its turn.
 
John said:
Nooo! He has to replace all of the capacitors in his monitor.

Outrageous. Apparently some people are really bored.
Click to expand...

It's obvious you have never had to help others and only yourself.
Otherwise you'd experience users calling in with a dead monitor who
happened to kick the plug out of the socket when they were moving their
feet under their desk, or the boob that calls in to report a dead
monitor but it's too dark to see behind the work desk because there's a
power outage in their area.
 
That was supposed to be sarcasm.
It's obvious you have never had to help others and only
yourself. Otherwise you'd experience users calling in with a
dead monitor who happened to kick the plug out of the socket
when they were moving their feet under their desk, or the boob
that calls in to report a dead monitor but it's too dark to see
behind the work desk because there's a power outage in their
area.
Click to expand...

That is entirely possible, but we may never know.

Actually I was bashing the other suggestions. Without knowing
anything about the original author or the monitor in question,
telling some stranger that he might need to replace all of the
capacitors in his monitor because it does not turn on sounds very
strange to me.

Not enough activity in this group lately.
--
 
John said:
That was supposed to be sarcasm.


That is entirely possible, but we may never know.

Actually I was bashing the other suggestions. Without knowing
anything about the original author or the monitor in question,
telling some stranger that he might need to replace all of the
capacitors in his monitor because it does not turn on sounds very
strange to me.

Not enough activity in this group lately.
Click to expand...

You somewhere in my reply - the one to which you replied - any mention
of capacitors? I figured you were berating me with the "really bored"
comment since it was to me that you replied.
 
Nooo! He has to replace all of the capacitors in his monitor.

Outrageous. Apparently some people are really bored.
Click to expand...
No, just frugal. I had a perfectly working and beautiful 24" monitor go out on
me, and i'll be damned if i was going to throw the thing out just because $10
in capacitors went out in it. Like i said, for someone like me who can mil
spec solder almost blindfolded, it was a nobrainer to fix and i was able to do
the desoldering and resoldering job with 12 capacitors in a matter of 20
minutes. But its not for the faint of heart.


Why would i want to throw away a $300 monitor?
 
That was supposed to be sarcasm.


That is entirely possible, but we may never know.

Actually I was bashing the other suggestions. Without knowing
anything about the original author or the monitor in question,
telling some stranger that he might need to replace all of the
capacitors in his monitor because it does not turn on sounds very
strange to me.
Click to expand...

I never said that. I said basically that its a common thing for LCD monitors
to fail that way. And its not always the whole monitor. Mine just happened to
be built with those cheap knockoff ones that bulged. At the very least , while
the OP has his monitor apart to look for a blwon fuse, he should at the very
least look at the power supply capacitors.

Just because you may not be capable of the task, quit shitting on other
peoples skills. The OP may be very capable of the task.

Not enough activity in this group lately.
Click to expand...

More people leaving their basements?
 
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