BenQ lcd monitor with No Power Light on.
Today came in an Lcd Monitor for repair.
Made in korea.
It's a 15inch lcd monitor.
Opened up the back cover and found power board very clean.
No burnt marks.
No bulging capacitors.
No leaking capacitors.
Everything looks perfect.
Took out pcboard and have a closer look for any cracks,
torn out links, cracked components, overheated coils, etc...
Even the soldering looks perfect.
Next, took out my multimeter, checked the main fuse for continuity.
Measured a few diodes, power Transistors, etc.
When I was turning the board over,
I accidentally pressed on one of the Transistors.
It bent easily. On closer look, all three legs came off loose.
It had severe dry solder joints.
So I pressed on all the Transistors to check on loose solder.
All eight components came out loose.
I did a clean surface soldering on most of the components.
Cleaned up with some thinner solution and leave it to dry.
Next, fitted the main pcboard back.
Applied AC power and found display lights up with the words "No Signal"
No need to change any components.
Just reflow some soldering done.
Fixed back the back cover and have it soak tested.
After an hour's use on my computer, I declared it good to use again.
There I have a happy customer today.
Monday, June 1, 2009
BenQ lcd monitor with No Power Light on.
Posted by kindheart at 3:01 AM
Sunday, October 5, 2008
Ever seen a burst capacitor? Well, this is also the first time I saw one so badly burst. Luckily I had my camera in hand. So I snap it and share it with all my friends. What causes the capacitor to burst or why do they burst? There's alot of factors that can cause these things to happen. Lightning strike, sudden surge of power, over voltage supply, current draw, all sorts of possibilities. ok..have a look.
Posted by kindheart at 7:15 PM
Wednesday, July 2, 2008
Sencore Switched Mode Power Supply Course Equipment.
Sencore have given many Electronics Courses all these years.
This is the best Equipment for teaching or learning Switched Mode Power Supply Hands-On Troubleshooting Course.
It is in a very detailed format.
Sencore makes it easy for students new and experienced to master SMPS courses practically.
It has all made built-in fault switches for troubleshootings.
This set is built complete inside a handheld casing.
It is in fully working condition.
View pictures above to appreciate.
I bought it for USD5000.00
If interested, make an offer.
You can contact me at firstname.lastname@example.org
View more electronics equipments here.
Posted by kindheart at 8:53 PM
Friday, February 1, 2008
I do lcd monitors repairs as well as computer servicing and repairs.
I do make a decent income out of it.
But everyday my email box is over stuffed by junk mails.
Today, I noticed one with making money with adsence.
There are lots of products and Ebooks out there
about AdSense but the problem with most of them
1. They're written by people who aren't even
big earners themselves
2. They don't ever go into the REAL detail of
HOW TO earn high amounts
That's why I was shocked when I came across
Michael Cheney's AdSense Videos site. He's
produced simple click and play videos that show
you the exact methods he uses to make $19,156
Michael's videos are different because they
show you step-by-step exactly what he does to
generate over $600 per day just using Google's
It's easy to see why all the big 'gurus' are
piling praise on 'AdSense Videos' and even if
you don't go ahead and get full access to all
the videos (which I recommend you do) - you
need to visit the site and get the AdSense
Mini-Course he's giving away:
All the best to you,
Posted by kindheart at 7:06 PM
Sunday, December 16, 2007
I do not know how to edit my blog.
As I am still learning and trying my best to get some repair tips across,
I hope you can bear with me on my learning process.
so we continue from last week on this Acer lcd monitor model AL1511 with
no power supply in.
Here is the picture of
the back cover removed.
And another picture
with the metal protection
removed. So you can see the
2 boards exposed.
Next picture you will see a closer look at the power pcb board.
In case you cannot see it clearly,
please email me so I can send
you a bigger picture of it.
This is the actual picture of
the faulthy power board.
I have checked the fuse,
which is in good condition.
Next I plug in the AC power cord
which is the main power supply
going into the pcb board.
Then I measured the big capacitor with
a multimeter switched to DC volts.
Here I obtained a measurement of 325 volts dc. Note that if you use
an analog multimeter, you must observe the polarity of the big capacitor.
For an analog multimeter, use the red probe on the positive and the black
probe at the negative polarity of the big capacitor.
From the picture the big capacitor is at the top right corner.
If you use a digital multimeter, you do not need to observe the polarity.
Then I will continue to check the diodes and transistors.
I will also observe if there's any capacitors burst or leaking
which you can see with your naked eyes.
Look out for any burnt out components.
Do you noticed that there's two components with heat sinks
in this picture?
These 2 are double diodes.
There's 2 diodes inside each component, housed in the same
One of the diodes is shorted.
You can checked it out with your multimeter.
It shows continuity.
This is the shorted diode.
Only 1 diode is shorted.
I replaced it and power it on.
The set then works perfectly.
Here is the display after assembling it back.
I do hope you enjoy my troubleshooting tips.
Do visit my webside often to check out more
monitor troubleshooting tips.
Good luck on your monitor repairs.
Posted by kindheart at 12:04 AM
Sunday, December 9, 2007
I began to start to observe the set.
Look at the picture.
Comes in no power at all.
Next picture shows the back portion.
Does this set looks familiar?
Acer model AL1511.
ok... Let's remove the 3 back screws.
Do you notice the screws?
Once removed, you can slide out the stand.
It is quite heavy.
Now let's pry open the back cover.
From the picture, can you see the clips holding the front cover. Just pry open all the clips top to bottom and at both sides.
Here's the cover removed.
Inside you can see some press button switches.
These are normal switches you can find in most lcd monitors.
Posted by kindheart at 1:37 AM
Saturday, December 8, 2007
A customer just brought into my workshop an ACER lcd monitor for
repair. It is a complete dead set. No Power so of course no display.
Normally I would plug it into an AC outlet to confirm if there's
really no power supply going in. Next I would check it's power cable.
Posted by kindheart at 4:26 AM