A guy brought to me a Mid 2012 MacBook Pro (non-Retina) that won't turn on. He said that he spilled something on it. Anyway, I don't see any sign of liquid even after removing the logic board and optical drive, so I am assuming that the keyboard backlit prevented the liquid from reaching the interior. So... (after reassembling the laptop) I disconnected the keyboard and battery and plugged in the power adapter. The laptop powers on immediately and seems to operate normally (using a USB keyboard). Now, I am very well aware that the power button is connected to the keyboard. I am confident that the keyboard is the problem and needs replacing, but I am looking for a second opinion (or more) because I don't want to pay return shipping if the keyboard isn't really the problem.