Chevrolet 2001 Express Van Owner's Manual page 84

There are several ways to lock and unlock your vehicle.
If your vehicle is equipped with keyless entry, see
"Keyless Entry System" later in this section for
more information.
From the outside, use your key.
To lock the door from the
inside, slide the manual
lever on your door down.
To unlock the door, slide the
manual lever up.
Power Door Locks (Option)
When a door is locked, the inside door handle will
not work.
Press the bottom side of the
power door lock switch to
lock all the doors at once.
Press the top side of the
power door lock switch to
unlock all the doors at once.
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