MacOS – Key combination not working when using the touch bar

keyboards are 2 layers of plastic film with tiny electric contact, separated by a third layer of plastic film with holes on the spot of every single key. when you press a key, the top and bottom plastic are pressed against one another inside the hole of the middle layer, and the electronic signal going from the top to the bottom layer tells your computer that the key is pressed.

problem is: separation is the same as an average good quality book paper sheet, or maybe the same as the aluminum sheet that makes a soda or beer can. also, the electricity that goes trough your keyboard is extremely tiny, and sensors are VERRY sensible, so your air battery can lasts longer. So even if you have a single hair touching those circuits, your keyboard would "break" the same way it breaks when you spill coffee or whatever liquid; even after the liquid dries, the coffee and the sugar are probably still there "pressing" your alt key.

solution: (this will probably void any warranty) open your computer carefully, remove the keyboard, dismantle all keys one by one, separate the plastic layers with surgical precision so you don't cause any ruptures to the electric "wires", then wash everything with a lot of water and very little mild soap, take extra care to remove ALL the soap, leave everything to dry in the sun (you know electronic components don't like humidity, right?) assemble everything together with "just-washed" oil free hands (don't touch the inner part of the sensors now). Doing all this, if you have any luck your keyboard might work 100% again... or maybe you might make it stop working entirely, who knows? =)

if you have some money, then backup you computer, go to the applestore and tell them you want to buy a new keyboard, because you broke the current one. they shall give you a brand new (refurbished?) one, and charge you only the new keyboard. or they might give the same one back to you, who knows? haha.

The problem you discribed is exactly the same that I have with my new MBP 15" Touchbar (2,9Ghz, Radeon 460). The reason why it's overheating is, that the fans do not automatically accelerate when there's a higher workload. They are continuously running at 2000 rpm.

My solution: Use iStat Menus

There you can manually increase the rpm to medium (3500-4000rpm) and high (4500+). You will see, if you manually adjust the fans, the MBP will work great and there won't be any overheating issues.

BUT that's not how a notebook should work. It must automatically adjust the fans. I talked to several apple support guys (In Germany) and they all told me, that they havent experienced such a thing yet. I did the same things like you, resetting NVRAM, resetting SMC and I even reinstalled the OS. Nothing helped.

It may be a firmware issue that will be fixed in the future. However it seems like just a minority of MBP Touchbar customers are facing this issue. Most likely I will exchange my notebook in January (since it's not available at the moment xD )