Try it with the fob not in your pocket?

 

Where is the fob when you are testing?

 

It happens when we are standing by the driver's side door with the fob in our hand. The doors lock fine.

 

Key FOB within about 3 ft. will unlock the hatch. See page 2-5 in the Owners Manual.

 

I will try standing very close to the rear hatch and pressing the lock button.

 

You are not understanding what's being said here. The Volt has a passive locking system "with key fob proximity detection".
If the Fob is near the car the rear hatch WILL be able to be opened by pressing the release button. Lock the car and GET THE FOB AWAY FROM THE CAR!! put it in your house or give it to someone and tell them to get 15 - 25 feet or more away from the car. THEN attempt to open the hatch. I think you will find it is locked (actually it is "always" locked) when no key fob is detected in close proximity to the car.

 

Lock the car. Put your fob in the house. Go back and try to open the hatch.

 

WHAT HE SAID^^^^
Technically the hatch is ALWAYS locked when the hatch is closed. There is no mechanical locking mechanism (other than the latch)
It simply will not release unless a FOB is in range when the soft-switch is pressed.
WOT

 

Funny thread!

Incidentally, is there any way to get the car to unlock the doors automatically like you can set it to lock the doors automatically? Pressing the button on the handle is so passée!