Chosen Solution
Sorry this is going to be long but I just wanted to explain the whole thing to not leave any room for confusion. A couple of days ago I was shaking a water bottle with a vitamin C tablet inside (stupid, I know) near my system and the cap burst open and sprayed my system’s keyboard with tiny drops. I quickly cleaned up everything and thankfully most of the drops were on the keys not underneath except for the space bar which was a little bit stuck so I quickly popped it off and cleaned the area with a cotton swab and put it back on. All the keys were working fine and weren’t stuck except for the space bar due to the liquid and the L key, which a couple of weeks ago got a little bit stuck for no reason. I took it to an authorized service provider and they told me they wanna replace the whole top case. I argued that there was no need for that, I just need the keyboard replaced and they told me that even though everything was fine, the water got to one of the water sensors in the touchbar so they need to replace the whole thing for a price that I wasn’t able to pay. So I took my MacBook to an unauthorized shop who told me that only the keyboard needed to be replaced (with the knowledge of the first shop telling me that 1 Touch Bar water sensor got damaged) and they did that but when I was testing my keyboard after the replacement, I tried to use my fingerprint to unlock it but it wasn’t working and it didn’t even ask for it and when I tried to add a new fingerprint it would say that the limit has been reached and right now I can’t use the Touch ID feature. The button still works and I can shut down and turn on the system using it and the whole Touch Bar is working fine but I was wondering if it could be that the liquid damage is the reason its not working anymore? Or could it be another issue and there is an actual way to fix it? Also should I be worried that my Touch Bar could be damaged in the future even though its working great as normal right now? And if it does get damaged (hopefully not) would I have to replace the whole top case or just the Touch Bar? Thank you for taking the time to read this long post and I apologize if I didn’t explain something well since english isn’t my first language. I would greatly appreciate any answer to any of my questions! Thank you again!
Lets look through this great teardown so you can see what your system looks like internally MacBook Pro 13" Touch Bar Teardown. Jump down to Step 11 to see the Touch ID/Power button you can see its independent of the Touch Bar. So clearly the issue is not the Touch Bar but the Touch ID button. This is where things get tricky! The button logic is tied to your logic board, you can’t replace one without replacing the other! So while your system is working presently its possible the Vitamin C that was in the water solution has collected on the circuitry. If we look up what Vitamin C is we can see it’s also known as ascorbic acid and ascorbate. The key word here is ‘Acid’ acids are corrosive some more than others and the concentration of the acid and how long it has to do its work also has a big effect on how corrosive. it can be. Sadly, you’ll need to go to an Apple Store or authorized service center to get the system shipped off to the repair dept nearest to you for them to replace the Touch ID part and reprogram it in order to get your system working correctly again. Its also likely they will replace the uppercase at the same time to repair the keyboard. While it is possible to replace the keyboard alone its a very big job and the results are not as good as just replacing the full uppercase. The issue is Apple riveted the keyboard to the uppercase so one need to cut the rivets and then tap the holes so screws can be used.
