Pontiac 1999 Montana Owner's Manual page 127

Canceling the Sliding Door Security Lock
1. Unlock the sliding door and open the door from
the outside.
2. Move the security lock lever all the way down.
The sliding door lock will now work normally.
Liftgate
To unlock the liftgate from the outside, turn the key in
the cylinder clockwise. To lock the liftgate using the
key, turn the key counterclockwise.
Open the liftgate using the handle above the license
plate. Once slightly opened, the liftgate will rise by
itself. Lamps in the rear of the vehicle will come on,
illuminating the rear cargo area (see "Interior Lamps" in
the Index).
NOTICE:
Be sure there are no overhead obstructions, such
as a garage door, before you open the liftgate.
You could slam the liftgate into something and
break the glass.
To close the liftgate, pull down on the handle, then
firmly shut the liftgate. Don't drive with the liftgate
open, even slightly. See "Engine Exhaust" in the Index.
A light on your instrument panel will warn you if the
liftgate is not completely closed (see "Door Ajar
Warning Light" in the Index).
yellowblue
2-31