Macbook Air won't power up
Mid-2012 Macbook Air, running El Capitan. Purchased as a Refurb.
About a month ago I received a message saying the USB ports were drawing too much power... but nothing was plugged in. A day later I shut down my MBA as normal. In the morning it would not power up. I made a Genius Bar appointment, but they refused to work on it and told me to buy a new one. I'm not really in the position to do that, so I took it to a shop. So far the guy has tried every reset and has replaced the charger, battery, logic board, and I/O board... Still won't power on. Fan doesn't even spin. Charger doesn't light up. Zip. Zilch. Nada.
Am I missing something? What else is there?
MacBook Air (13-inch Mid 2012)