Hi, For a while, we had to press the tactile switch many times and soon or late, the logic turned on. Then, to avoid this, we left the monitor on all the time. When the computer was turned off, the monitor was turning off but was not really turned off by its switch, the led I think was switching to an idle color, so when turning the computer on, we did not have to face any problem because the monitor was turning on. Now, it is dead. that workaround does not work any more. At a service shop, they told us an IC has to be changed. We do not know which one. Can anybody help on that? Tanks.
Kbzaloka: That is not a solutiom you posted. If you can't help, then don't post anything.
russolini: I'm having the same problem with a monitor on my bench right
now. I did fix another problem it had. It seems some of the
surface-mount electrolytic capacitors are going bad. I will let you
know if I solve this fault too. If anyone has lines going through their
display, and the sides look ripped or torn, your pixel clock is not
working correctly. Try replacing the 22uF capacitor C46
right above the pixel clock generator IC09. This should smooth out the
3.3V supply for this IC and correct the problem.
Posted on May 06, 2009
I have solved this problem on this model.
The power switch goes to IC30. Once again, in this circuit there are
two surface-mount electrolytic capacitors. Lucky for me it was the
first one I replaced.
IC30 is in the lower right corner, to the left of the LED on the main
board. To the left of the IC is a 22uF electrolytic capacitor C112..
Replace this capacitor and your problem will be solved.
To remove, heat one lead with solder iron and push capacitor slightly
in opposite direction. Then heat the opposite lead and push in the
other direction. Repeat until capacitor comes off. BE VERY GENTLE OR
YOU WILL DAMAGE THE TRACES ON THE BOARD.
Once removed, add a little solder to the trace pads. You don't have to
use a surface-mount capacitor to replace it. You can use a normal
electrolytic capacitor (22uF @ 16V) and trim the leads to be only about
4mm long, then bend them out in opposite directions. Place
capacitor on solder pads making sure you have the polarity correct.
Heat the solder on one lead and remove the iron, then heat the solder
on the other lead and remove the iron. Job done, perfectly working
monitor.
I didn't put my name in the solution (comment). Mergatroid solved this problem.
I just wanted to say thank you, thank you, thank you, Mergatroid -- this worked perfectly!
×
Well my friend, there are people that have courses , studies , school etc to know "which one" they are called "Technician, Engineer,etc" they can help you...
Posted on Jul 13, 2007
278 views
Usually answered in minutes!
I have about 6-7 Viewsonic VG150 LCD monitors (both beige and black) that all exhibit the same problem of "the faulty power switch", if that's indeed what it is.
Problem: Power switch doesn't work, until pressed repeatedly and rapidly. Once turned on the monitor works fine, and the power switch will turn it off correctly, but then you'd have to repeatedly and rapidly press it again until it "catches". Upon close inspection the power LED flickers the more rapidly you press it, so I imagine there's some sort of voltage or capacitance problem, but I have exhausted all my good ideas on what might be causing it. I've taken them apart and tried resoldering and replacing just about every electrolytic capacitor on the logic board.
This is incredibly frustrating. Can someone suggest something else to try replacing, or a possible cause of the faulty power switch?
HELP! PLEASE :)
×