I accidentally spill some liquid on the keyboard of my MacBook Air. It wasn't too much and I turned off the computer right way. The computer works perfectly fine, but after I log in the keyboard and trackpad stop working. Does anyone have any clue on what is going on?
As physical connectors heat and cool, they may loose contact with what they are connected to. Rather than logging in immediately upon boot up, let the computer get up to temperature. In other words, wait 5-10 minutes. Can you log in at that point? If not, the increased heat from normal startup may have exposed some hardware damage done by the liquid.
After letting it siting for a couple of weeks the computer started working normal again. So I'd say that in cases like that it would be a good idea to let the computer off as long as possible and at least 72h. (The computer wasn't actually mine and the guy turned it on after 3 or 4 hours).
I have had the same problem (only without the liquid) and I have find the solution... I was ready to restaure an old back up from time machin. To do so, I have before '''clean the desktop'''. I classified and '''removed all the desktop documents and restart the computer'''. Miracle, my macbook worked fine again. I think a document on the desktop was the cause of an interference with the keyborad and trackpad.