Chosen Solution
The buttons on my MacBook Pro Retina 15’’ Mid 2014 do not work properly anymore. For example, when I press 1, the volume control pops up. When I press 2` the apostrophe appears. When I press 3§ that random squiggly S appears. When I press 4] the bracket appears. When I press 5[ the other bracket appears. When I press 6=, the equals sign appears. When I press 9, the cursor moves. When I press Arrow right , the 8. appears. When I press Arrow up , the 9. appears. When I press equal, 6= appears.
This happen when you spill liquid on the keyboard, you will have to replace the whole keyboard to solve this problem.
