The SMC is the system management controller, that controls some things like the keyboard.
For the backlight: What is happening when you're trying to adjust the brightness following these instructions?
Do one of the following:
- On all Mac computers: Choose Apple menu
> System Settings, then click Keyboard
in the sidebar. (You may need to scroll down.) On the right, drag the “Keyboard brightness” slider to adjust the brightness. Drag it all the way to the left to turn backlighting off. - If your Mac has keyboard brightness keys: On the keyboard, press the increase brightness key
or the decrease brightness key
. To turn backlighting off, keep pressing
. - If your Mac has a Touch Bar: In the Touch Bar, expand the Control Strip, then tap the increase brightness button
or the decrease brightness button
. To turn backlighting off, touch and hold
.
Will it not increase or decrease at all?? Then it could be a hardware issue with the backlighting