Same Problem with No Resolution Yet
I have had the same issue. Just took my 2012 Focus SE hatchback to the dealer for the 4th time for the airbag light issue. They said that they have replaced everything at this point. They have me charting when it comes on again to see if there is a trigger.
Picked it up from the dealer this last time on Friday, light came on again on Saturday...and Sunday. Still no clear pattern causing it, yet. I love this little car but won't be able to keep it if they cannot get this airbag issue fixed.