Option (⌥) or Alt: Start up to Startup Manager, which allows you to choose other available startup disks or volumes. If your Mac is using a firmware password, you're prompted to enter the password. Option-Command-P-R: Reset NVRAM or PRAM. MacBook Air 11' has slightly different keyboard, with smaller top and bottom row keys to accommodate smaller laptop size. Newest MacBooks Pro with TouchBar don't have upper F keys row, instead, they have a touchscreen which changes displayed options based on context.
I have a MacBook Pro (Retina, 15-inch, Late 2013) whose CTRL and OPTION-ALT keys on the left side seem to have become 'shorted' somehow.
Keyboard mapping utilities, including Ukelele and Apple's Keyboards Preference/Input Sources show that whenever either of these keys is pressed, the utilities show that both keys are pressed.
This only happens with these two keys. The ALT-OPTION key on the right side works normally.
Option Key - Wikipedia
If I plug in an external USB keyboard, all the external keyboard keys work properly, including CTRL & ALT-OPTION on both sides.
Any suggestions as to how the MacBook Pro keyboard CTRL and ALT-OPTION keys might be restored to their normal function?
Alt Key On Macbook Pro
Macbook cover and keyboard set. MacBook Pro with Retina display, macOS Sierra (10.12.1), 15' Late 2013
Posted on Nov 8, 2016 2:43 PM