Question Diagnosing cause of flickering on a known faulty monitor ?

[guitarher0]

Hi Toms,

I have purchased a known faulty AOC C27G3 165Hz monitor for the purposes of diagnosing and repairing. The issue described by the seller was that the monitor flickers and he was on point.

Prior to purchasing I did a little research and found that AOC monitors sometimes have a little trouble with refresh rates and an interim fix would be to lower the refresh rate to 60Hz and/or change the cable as well as test with a different output device.

So far this has been tested with a PS4 as well as several computers at pretty much all of the refresh rates with completely different computer setups as well as all the latest drivers installed and still the fault persists.

I took it apart tonight to see if there was anything obvious or easily diagnosable. While the monitor is easy enough to get apart and check over all the boards etc there are no signs of a fault with a visual inspection of the circuitry.

During disassembly I took down the part numbers of both the power board and the logic board and they are as follows:

715GB709-M0B-B00-004X (Logic or Driver board)
715GB654-P02-000-001R (Power PCB)

At a guess, and I can only guess at this point I'm assuming the logic board has had a failure solely due to the fact that there is nothing wrong with the power board - All monitor functions are testable, the screen displays with all functions working correctly on a power level.

This is despite the monitor not only flickering but displaying a washed out image or one where the contrast looks or appears to be so far off all of the colours are washed out no matter what setting you put it on (And i've been through all the monitor settings as well)

The only other thing I can think of is that it has a direct panel fault - In which case it's probably discardable as the likelihood of me finding a replacement panel is pretty impossible in my country (New Zealand)

I also cannot find any reference (Let alone a purchasable component) to the logic board on the internet even searching the entirity of Google or attempting to find it on eBay which presents another problem if it were just the logic board I needed to replace.

Are there any monitor experts out there that could give me some advice on this? Whether it's worth putting away until a replacement logic board becomes available given as it's a relatively new model or whether you think it might be a panel fault?

I'm happy to provide pictures and or videos of this to show the fault if required.

Thanks in advance for any help with repair of this monitor!

 

[helpstar]

sorry, but if out of warranty -> trash
you could mearure the whole board for faulty parts, or resolder some connectors, but most likely it´s not worth it.

 

[guitarher0]

Cheers but i'd rather not trash it just yet. If I did run some measurements and found a board to be faulty and I could directly attribute this to the cause of the problem it looks to be a pretty easy job to replace them.

The only reason I'd trash it is if there were a panel fault which would render it unrepairable and worthless to me.

I did do some research and the replacement logic and power boards are easy to find and not to expensive. Even the whole set (Both the logic and the power board) are available for about a fifth of the price of the monitor (new) in my country and the logic board alone is a lot cheaper so it would be worthwhle repairing if I could diagnose it to a specific part.

I might run some tests on the output voltages of the boards next time I have it apart to make sure it's not dipping down somewhere in turn directly indicating a fault but also indicating which board to replace though guidance would be greatly appreciated in terms of diagnosing hence the post.