2016 MKC Electrical System not reponding to a newly installed battery

Did you use a saver tool before disconnecting main power? It plugs into OBD 2 port to keep the computers factory settings alive and keeps the security system from disabling the vehicle. So recheck your work, make sure you didn’t leave one of those plastic post protectors on the battery, then run the security disarm procedure in the owners for your model. After the security system allows you to start the engine then see just how many accessories don’t work or don’t work right, if any don’t work then you need the dealer to do a flash on the computer to get then back. In my area that runs about 120 bucks.

Answer not posting

I'm guessing that when you changed the battery, you didn't use a memory saver. That little device maintains electricity in the car while the battery is out. So you probably just blew the main fuse in the box under the hood: that's the big fuse that's bolted in.