GMC 2008 Acadia - Manual (Page 98)

The liftgate can also be closed by pressing the power
liftgate button next to the liftgate latch. Press the button
a second time during liftgate operation to reverse that
operation.
The power liftgate may be temporarily disabled under
extreme temperatures, or under low battery conditions. If
this occurs, the liftgate can still be operated manually.
If you shift the transmission out of PARK (P) while the
power function is in progress, the liftgate power function
will continue to completion. If you shift the transmission
out of PARK (P) and accelerate before the power
liftgate latches closed, the liftgate may reverse to the
open position. Cargo could fall out of the vehicle. Always
make sure the power liftgate is closed and latched
before you drive away.
If you power open the liftgate and the liftgate support
struts have lost pressure, the lights will flash and a
chime will sound. The liftgate will stay open temporarily,
then slowly close. See your dealer/retailer for service
before using the liftgate.
Obstacle Detection Features
If the liftgate encounters an obstacle during a power
open or close cycle, a warning chime will sound and the
liftgate will automatically reverse direction to the full
closed or open position. After removing the obstruction,
the power liftgate operation can be used again. If the
liftgate encounters multiple obstacles on the same power
cycle, the power function will deactivate, and you
must manually open or close the liftgate. The LIFTGATE
OPEN warning message in the Driver Information
Center (DIC) will indicate that the liftgate is open. After
removing the obstructions, manually open the liftgate
to the full open position or close the liftgate to the fully
closed and latched position. The liftgate will now
resume normal power operation.
Power Liftgate Button Near Liftgate Latch
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