An LCD Computer Screen With A Delay In Powering On Repaired. Model: Mag MS-776K
The screen belonged to my sister; I gave her this screen about 5 years ago and today when she tried to power the screen on, it took about ten minutes to show a display and the power light was flashing on and off.
I took it down to my shop and checked it out.
Since it was delaying to power on, my chain or thoughts were in the direction of bad capacitors on the output section of the power supply.
I started the disassembly process and first thing to go was the main frame, then the six screws holding the pan to the plastic housing.
I like the idea of having a shield over the main and power boards inside.
Few screws off and I was able to get inside.
As seen, I was getting the right voltage from the main power source and when I checked with the naked eye, I was not able to see anything wrong like cold solder joints or anything bad in there.
The capacitors look fine but when I tested with ESR meter, all six capacitors tested badly with high ESR reading so I had to replace all of these parts with new ones.
They were 470uf/25 volts and I replaced all of them, put the computer screen back together enough to test it and…
The screen was up and running. I installed it back on my sister’s desk top and it was working just fine.
Mission Accomplished.
This article was prepared for you by Waleed Rishmawi, one of our ‘Master Authors’ and currently working in the Bethlehem area of Palestine repairing electrical and electronic equipment.
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Note: You can check his previous article on A Flash Light With A Broken Charging Port Repaired. Model: XLM-P70
Albert van Bemmelen
November 8, 2024 at 8:24 pm
I guess finding all six e-caps with a bad ESR resistance was quite unexpected.
And a happy sister was worth fixing it!
Waleed Rishmawi
November 8, 2024 at 11:54 pm
Yes they all looked good but ESR meter found the fault and was repaired. Have a blessed day
Mark J
November 9, 2024 at 3:54 am
Waleed well done on the repair. Take care.
Waleed Rishmawi
November 9, 2024 at 5:29 pm
Mark: thanks man. have a blessed day
Parasuraman S
November 9, 2024 at 1:27 pm
A successful fault finding and repair; thanks to ESR Meter. A job well done to yet another relative! Great service in both senses!
Waleed Rishmawi
November 9, 2024 at 5:30 pm
Parasuraman: yes, ESR meters are the best and it can reveals things we can not see with out naked eyes. thanks for you comments and have a blessed day
Yogesh Panchal
November 16, 2024 at 12:57 am
Good Fix! Waleed