Chevrolet 1995 Astro Cargo Owner's Manual page 62

There are several ways to lock and unlock your vehicle:
From the outside: Use
your door key.
From the inside: To
lock front doors and
sliding side door, slide
the lock levers down.
To unlock the front
doors and the sliding
side door from the
inside: Slide the lock
levers up.
Rear doors cannot be manually locked from the inside.
To unlock the rear hatch and Dutch doors from the inside: Push the top of
the HATCH REL switch.
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