keyboard backlight is no longer working after upgrading to MacOS Tahoe

Have not seen this, either. Adjusting keyboard brightness works normally on my M4 Pro MBP with 26.0.1.

See if the problem is present when you boot in safe mode, which disables 3rd party extensions and performs some system cleanup.

Start up your Mac in safe mode - Apple Support

Else, bugs can be reported to Apple here:

Feedback - macOS - Apple

nathanbeach wrote:

I haven't seen any others having this same issue with the Tahoe upgrade, so I thought I'd ask.

My keyboard backlight no longer works after the upgrade. Or at least it's at a very very dim level and I cannot adjust it. If I move the keyboard brightness slider in Control Center, it just resets to 0 when I release the slider. This is on a 2020 intel-based macbook pro.

Really a bummer because I often use my laptop in low light conditions and now cannot see my keyboard. Thanks for any tips.

PS: yes, i've tried rebooting + resetting the smc/bios/whatever it's called, etc...

Are you saying this is new with 26.0.1 but was not with macOS 26.0....? This is not clear

To be proactive you can file a bug report / submit your Apple Feedback here: Product Feedback - Apple

On an Intel mac resetting the System Management Controller for back light issues

Reset the SMC of your Mac - Apple Support

no resolve try as well

—resetting NVRAM/PRAM Reset NVRAM on your Mac - Apple Support

(get at least two-three rounds of the chimes when holding the NVRAM Reset)

Still no resolve you can try simply reinstalling the macOS on top of your existing macOS

How to reinstall macOS - Apple Support

In general unplug all non-essential peripherals when testing

Uninstall all third party apps that are Cleaners/Optimizers/VPN/Anti-Virus

all known to cause issues on the macOS

Works on my M1 MBA. Perhaps it's an Intel issue.

My keyboard backlight does not come on when I first start up my MacBook Pro since the upgrade to Tahoe. However, after I have logged in it starts working.