Welcome to Justanswer.com, my name is ***** ***** I will do my best to assist you.
Lets try to master reset your device. ( this wont undo the map updates you did, but should get the device working again)
First, disconnect the garmin from your mac and turn it off. Then, follow the steps in this short video to reset the unit.
Once complete, your device should turn on and work normally. Let me know if thats the case and the device is working after trying the master reset, or let me know if it didnt work and you need more help. Thank you!
I strive to provide great service, and greatly appreciate a 5 star rating clicked and submitted when you are satisfied.. I always answer follow up questions.Dustin S.Senior Technician and Network Switching Systems Operator / Maintainer.