Samsung Ace 3 (S7270L) - dimming not working
For those of you whose phones' dimming function is not working after testing it in the "hardware" testing menu (*#0*#), the problem might not be your hardware after all.
I have rooted the phone and have uninstalled as much stuff on the phone as possible. I don't recall uninstalling anything that may have caused the dimming of the phone to stop working. Moreover, I don't have an idea when the auto-brightness stopped working as I've installed "bluelight filter" app. I just discovered this malfunction issue for a month and I thought part of the phone is "broken".
Nevertheless, before I've completely given up on the phone, I resorted to revert it back to stock rom. And the issue is solved! The software part might have messed up with the hardware, causing the malfunction of auto-brightness. Hope anyone who experience this issue can resolve it too, if your problem is the same as mine though. Good Luck!