Buzzing in viewsonic VA2407h LED monitor

[CyrusPhillip]

Hey forum people, I am new here and I want to get my problem solved. I am possessing an LED monitor VA2407h from viewsonic with bezel design. I got buzzing from it since yesterday. I search about this issue on the internet and what I found is that problem might be of the capacitor.

If I replace capacitor in my monitor the trouble will be over. But my question is which capacitor(any brand) should I use? A good capacitor can resist buzzing for a long time.

 

[Bluejets]

There are many capacitors in a monitor so in this instance assuming the buzzing is coming from the power supply section.

One can do a visual check to see if any are bulged on the top or leaking as an indication of a bad cap.

How competent are you at electronic repair...?

 

[CyrusPhillip]

There are many capacitors in a monitor so in this instance assuming the buzzing is coming from the power supply section.

One can do a visual check to see if any are bulged on the top or leaking as an indication of a bad cap.

How competent are you at electronic repair...?

Okay! @Bluejets Read your reply and it might be the situation of bulging. I am not an efficient repairer for electronics, but I can read some stuff and apply it on my LED screen monitor to solve such issues. After reading your reply I surfed the internet again and this is what I found https://www.instructables.com/Fix-a-Malfunctioning-LCD-Power-Supply/. Can this be my solution?

 

[Harald Kapp]

It can. Note that you may not see the brownish crust on top of a capacitor. A strong and visible bulging of the top is a sure sign, too, even if the capacitor is still closed.
Start by disassembling the monitor and taking good photos. To upload the photos note the size limit (< 300 kB/photo, <100 kB works best).

 

[Bluejets]

Okay! @Bluejets Read your reply and it might be the situation of bulging. I am not an efficient repairer for electronics, but I can read some stuff and apply it on my LED screen monitor to solve such issues. After reading your reply I surfed the internet again and this is what I found https://www.instructables.com/Fix-a-Malfunctioning-LCD-Power-Supply/. Can this be my solution?

Just be careful poking around in the power supply section as there is some high voltage dc (300v+)
Good caps in there can hold a decent wack for quite some time after power down.
I tend to approach any (powered down) caps , especially the larger ones, with a 1K5 5w resistor with a couple of leads soldered on to discharge any caps.

 

[shrtrnd]

As long as you open it up to look around, listen to identify WHERE the buzzing is coming from.
I wouldn't leap to the conclusion that it's a cap, although a cap might be causing the buzzing somewhere else.

 

[dave9]

Okay! @Bluejets Read your reply and it might be the situation of bulging. I am not an efficient repairer for electronics, but I can read some stuff and apply it on my LED screen monitor to solve such issues. After reading your reply I surfed the internet again and this is what I found https://www.instructables.com/Fix-a-Malfunctioning-LCD-Power-Supply/. Can this be my solution?

It is a little incomplete in that it did not mention that the replacement capacitors typically need to be very low ESR for good lifespan (except the biggest brown one on the right in the picture below). One make and model on Digikey that would qualify and that I've used in the past is Panasonic FS series, though most if not all major brands have something that'd be suitable.

I agree that it's unlikely to be an electrolytic cap making the noise, more likely a ceramic disc cap if any, but could cause a resonant frequency in an inductor or transformer. Below appears to be the power board for your model: