2013 MKZ Hybrid here and I think the battery has just started to fail. Car wouldn't turn on and the center display said something like "disabling systems to save power". I hooked up 10amp 12v source and car turned right on immediately. Ran a 2amp trickle charge on it for 2 days and charger said it never got above 80%. Went to try and turn it on after disconnecting and nothing works at all. 7 years out of a car battery is pretty darn good. New battery at $130-160 is pretty pricey though! Trying one last trickle charge of the battery while i have it out of the vehicle now with no draw, but pretty sure it's toast anyway. I just did a bunch of work trying to seal the truck area of the car recently after finding some water leaks when raining, so I was suspicious at first that I caused a problem, but I think just a coincidence.