If an auto-airlock is leaking, and you walk into it, the automatic action will repair the leak rather than open/close the door.
This is handy, but probably not intended :D
The automatic airlock is a great upgrade, and I like that it takes a normal airlock as a crafting component.
I've already had the chance for it to save my life as I stumble back to base with the suit at zero O2 remaining.