Problem: The moment I powered up the screen, the picture came on and then off. Then it started to come on and off very fast.

When the picture came on and off repeatedly, the standby power LED stayed on all the time. Which gave me the indication of bad back lights, bad capacitors or bad power supply? I opened the back cover of the LCD screen and the first thing I did was to check on the CCFL back lights. I used the CCFL tester LST01 to test the back light and to my surprise, all of CCFL tested fine.

I powered up the screen again and checked the voltage on the inverter IC and the 12 volts were there but not very steady. It was consistent with the screen coming on and off. What I mean is when the picture was on, I could see the 12 volts but when the picture was not there, the 12 volts are gone. I unplugged the screen from the main electricity out let and I took the PC board off. I scanned the whole area to see if there are bulged capacitors but there were none. I used the blue ESR meter to check the main capacitors and found two bad capacitors that had high ESR readings. One of them was 1000uf/25 volts  and the other 220uf/35 volts. I replaced the two capacitors with new one and fired up the LCD screen. The volts on the inverter was steady but not for a long time. It was shutting on and off but this time it was slower than before.

I started checking the board for bad soldering joints. When I used the magnifying lens to do that, I found a lot of bad soldering joints. I re-soldered most of the power supply area and some in the high tension area. I powered up the LCD screen and checked for the 12 volts on the inverter IC. The 12 volts were steady and nice.

I put the LCD screen back together then, I powered up the screen. What a wonderful sight it was when I saw the picture on the LCD screen and this time, it stayed on. The colours were nice and the picture was clear. The LST01 is a good meter and it helped me to save testing time. Also the blue ESR meter was a good asset as well. I recommend these meters to anyone involved in electronics repair.

About

10 years of practical electronics. owner and operator. I service the Bethlehem area in Palestine. I repair Xbox 360 and all play stations and modify their power supplies. also repair lcd and Plasma tv sets, and lcd computer monitors. I have a degree from Bob Jones University in general business and one year degree in Industrial electronics. a intensive course in Media. I also work as a camera and audio man as a free lancer. Also great experience in video editing and installing surround systems for home and movie theaters.

2 comments on “Repaired- Hannspree LCD Monitor Model#M19W2 With Display Blinking Problem

  1. jonelism says:

    Hi there,

    i have problem w/ my monitor lcd. Blinking power led, its always blinking but ni display.. can you teach me? how to repair? email me at bci_joniffer@yahoo.com..

    thanks a lot..

    -JONELISM-

  2. veronel says:

    buna am si eu un LCD Hannspree de 28 si are o problema se aprinde ledul rosu iar cand ii dau power se face verde dar ecranul nu se aprinde,dupa care am constatat ca nu am tensiuniile de 12 v si 24 v cea de 5 v este imi puteti spune ce problema ar avea daca se poate multumesc

Leave a Reply

Your email address will not be published. Required fields are marked *