Pontiac Montana SV6 2008 Owner's Manual page 105

If an object obstructs the power sliding door(s) while
it is closing, the door will automatically reverse to the
open position, provided it meets sufficient resistance.
Resistance must be as strong as the force of the closing
door, or stronger. The force of the closing door increases
significantly as the door approaches the latched position.
The driver's side sliding door is designed to open only
a little if the fuel door is open. If this ever happens,
do not try to force the sliding door. When the fuel filler
door is closed, the driver's side sliding door can be
opened normally.
CAUTION:
{
You or others could be injured if caught in
the path of the sliding door. Make sure the
door path is clear before opening or closing
the door.
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