I found a few people with similar problems, but since I have soldered two things in my life I am afraid to break it if I just try random things. Ok so when I turn the monitor on the BenQ logo appears very dimmly and a split second later it dissapears, so from what I read it is probably something with the inverter. I have opened it and have the main circuit board all ready to go. Some people have said that resoldering the tranformer connections might help.The capactors are not bulging or anything so I guess they are fine. So please tell me what I need to do with specifics because I cannot differentiate between all the components on the circuit board. Thank you. P.S. I am very novice, just 2'nd year mechanical engineering, not really a circuits guy.
Most 17" BenQ monitors share a very similar power/invertor board setup.
This is a very common fault.
First check the 4 small invertor transformers for cracks.
Second there will be 2 rectangular capacitors (usually grey) between a pair of transistors .
These transistors have a code C5707 on them. (2sc5707)
What usually happens is the top capacitor gets cooked from the heat and shorts out the transistors. This in turn can blow the fuse FP801 on the board. (it is a 3 amp fuse, soldered in type thats either black or yellowish in colour.
To fix this you need to relace the capacitors, (0.22 picofarad 250 volt) probably the transistors, and maybe the fuse.
To test the transistors use either a multimeter or continuity tester on the legs of the transistors. If they show a dead short between any pins they will need to be replaced.
Got the same problem if you have a reaaly bright light going over the screen you can dimily see everything ( very dimmly ) i not a comptuer expert but im pretty sure the backlight inthe moniter is stuffed
Density, I agree from what you have described it might be the inverter board, however, I wouldn't start tearing and replacing based on your description just yet. With the computer on and the monitor power LED green shine a flashlight in the lower left hand corner of your screen. Look for the Windows ?Start? button, if your backlight and/or the inverter board is not working you?ll see a faint ?start? button if you look closely. If that is the case I wouldn't recommend randomly re-soldering or replacing parts on the inverter board. Unless you physically see damage or have the ability to trouble shoot the failure to a discrete component I would suggest replacing the entire board if it is economically worth it. Depending on the monitor this is usually an economically repairable problem. Let us know if you have any other questions and please don?t forget to rate this posting.
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