Chevrolet 2005 Astro Owner's Manual page 91

Hatch Release
You can use your key to unlock the hatch and all of
the other doors from the outside. Insert the key into
the hatch release button and turn it counterclockwise.
All of the doors will unlock.
You may also use the remote keyless entry transmitter.
See Remote Keyless Entry System Operation on
page 2-4.
The hatch can be opened or closed without a key if the
door lock system is unlocked.
The interior light will not turn on if the rear doors are open.
To open the hatch, unlock it, then press the button and
lift the handle located in the center of the door.
To lock the power lock system from the outside, insert
the key in the hatch release button and turn it clockwise.
All doors will lock.
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