Chosen Solution
My MacBook has developed a habit of not registering I, O or U unless I hold them down for several seconds. SOMETIMES nothing happens at all. Sometimes, they register. And, annoyingly, SOMETIMES, they work fine… but it’s becoming a a real problem. I have taken the keytops off and and cleaned underneath but I fear it could be a software issue or worse. I have reset the SMC and PRAM. I now use a bluetooth keyboard on top of my keyboard. What a pain! Any ideas?
A common issue is the battery has swelled up pressing on the cables. Lets get a view of your batteries health, to get a better view of things, install this gem of an app! CoconutBattery take a snapshot of the apps main window and post it here for us to see Adding images to an existing question
Remove the keyboard cable, clean the contacts with IPA, reassemble and give it a try. If it persists you may need a new top housing.
