Headrest deployed, it can be inspected upon request. Headrest eployed after just closing the door, it impacted hard against the back of my head while parked, had this happened while driving it would've caused a serious accident. After getting home safely I did a quick resesrch of this issue with several reports from other car owners, plan on going to the dealer tomorrow to report the issue with them. Since it just happened I will report it to the dealer tomorrow but will keep a record for insurance report. No, there was no signs or alarms when the system failed, just with a visual inspection you can see broken plastic where it was supposed to be connected.