If you pull the metal key out of the fob and try to lock the doors manually, you may notice something you'd previously overlooked. There is no cylinder to turn!? There is a small slot on the bottom of the driver's door handle, but how does it work? My key only goes in about half way, and doesn't turn. What am I missing?

I didn't find the right solution from the Internet.
References http://www.chevybolt.org/forum/129-safety-features-technology/9162-anyone-figured-out-locking-doors-key-not-fob.html
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