Chosen Solution
My keyboard backlight works great manually, but it won’t adjust its brightness automatically in dark environment/low light condition. I tried SMC & PRAM reset, but nothing change. I have sought support from Apple, but still no result.
Something might be wrong with your light sensor. Due to how new this computer is, I suggest that you bring it into an Apple Store and see what they say. Yes, I know Apple Stores aren’t typically much help but it never hurts to try. Also, if they quote you a huge bill of replacing the screen (as I foresee it now, but there might be a setting that needs to be changed), ask if you are currently under warranty.
