Dead pixel on imac 21.5 (late 2009)

[kyaw]

Hi, I spotted one dead pixel(stuck pixel) on my imac at yesterday.
i tried to fix using JScreenFix. also not working..
I asked the customer service reseller from apple, they told me my iMac not eligible to get the replacement due to one dead pixel.

so is there anyway to check dead or stuck pixel? and how to fix the one?

thks

 

[deathnomore]

see if this helps

https://forums.macrumors.com/archive/index.php/t-235987.html